As a non-machinist I learned why there are 2 different dies for chasing threads properly. Years ago I bought a set of round and hexagonal couldn’t tell why they were different until now. Even at 70 years old it is fun learning new things. Thanks Adam.
One thing I've learned about master machinists. They always know what the right tool for the job is and they always use it. I see so many new tools on your channel that I didn't even know were the right tool for the job.
Appreciate you mentioning and using safety glasses when demonstrating this. Way to many TH-camrs fail to emphasize and teach the importance of good safety habits on their channels. Having a Dr. operate on the sclera part of you eye (white part), while awake, with only local anesthesia injected into the eyeball, to remove embeded foreign debris, is no joke! Doctor said that he performs this procedure a couple times a month! Now ask me how I know this. Keep up the good work Adam! Thanks.
I have had metal, and the resulting rust stain drilled out of my eye twice. Both times while wearing glasses when I should have had a face shield. It's about zero fun.
Hi Adam, The split dies have to be adjustable to allow for wear. Also, it is not that they are set up to size by the manufacturer; it is the handle that allows different degrees of expansion because of the fit tolerance of the hole that the die sits in. If you are threading a very hard material then tighten the screw opposite the split to open up the die a bit, cut an oversize thread, then loosen that screw and tighten the closer screws to cut a deeper thread, thereby saving your die doing all the work in one go and wearing out faster. If you have to match a worn threaded hole you can open the die to make the thread a bit bigger, or, to match a worn tap or bolt/stud, close the die up to make it a bit smaller. It is the handle that limits the expansion of the die stopping it from breaking which is what your friend did with the die nut (sorry, I am English; we use split die and die nut to describe them). Never use a split die without a handle, it will guarantee to break. Keep up the good work Andy
Old school industrial maintenance man here, and I'm pretty up on all the "things" related to stuff like this, but I had never thought about the preferential uses of hex vs round dies. Makes a hella lot of sense, though, and explains many of my cuss fests in trying to thread even the most basic steel rod with hex dies. Even after 30 years of doing this stuff , I'm always thrilled to learn new things like this. Thank you very much for stuff like this!
There are some really good people in this world and this guy is definitely one of those. So grateful he takes this time out of his busy day to explain the difference between thread cutting dies and thread chasing dies. He saved me a big headache.
Something you could also mention Adam is to pay attention with any rethreading die which side of the die has a chamfer, that must always face towards the threads so the die will begin to cut gradually. Great videos!
Great video Adam, I reckon probably 75% of people did not know the difference between the two types, I am in the 75%....Every day a school day! Thank you!
Adam, you offer the best of what YT has to offer - I learn something in every one of your videos. That's the pinnacle of content production. Thanks. Please keep them coming!
Hi Adam, it's always nice to learn something new! I did not know the diff between round & hex, now I do!! Thanks, I do enjoy Shop Talk! Keep 'em coming!
Thanks for the info and the video. You have an uncommon friend, usually one gets the broken tool back with a "I owe you a new one" and that's the end of it as if the acknloedgement of the debt is alll that's really required. I long ago stopped loaning tools out to anyone that's not my father. (He's the sole exception; if he broke a screwdriver he'd feel so bad he'd try to buy me a new set.)
I learned something new today! For 40+ years I've been using hex dies to try to cut new threads in a rod with poor results usually. Being a diesel mechanic, most tools were purchased off of the tool trucks like Snap-On or Mac. They all sell tap and dies sets, and they have hex dies in them. No where do the tell you it's for thread repair not cutting virgin threads! The tool jockeys just want to sell you something. Adam you rock!
knew about round dies made for cutting, but glad you straightened out me on the hex dies,I've got dads old tools and they included those hex so now i know only to use those to chase.Thanks Adam
My grandpa was a machinist, he died in '79 when I was just few months old. Even though I don't remember him I was always impressed by his work, machines, tools and workshop he left. He even made a small tractor for a farm he owned. I wish I could learn craft from him...
Tomasz Sz sorry to hear that about your grandpa, but that's the way it is with good people, they left a lot of good stuff to be learned and remembered, I also lost my father when I was 13 but at 41 I keep learning from stuff and tools he left.
Hi Adam, correct in all cases, the round/adjustable die is to allow for thread size based on material difference, pinch it in for tougher materials, and also for a smaller size if the thread is to be plated. You can get oversize taps when the female thread is to be plated, chassis for example. Great informative video as always.
My father taught me the same. He also showed me that the round dies with the adjustment screw in was used to step it down as you thread. I've done it several times on head bolts on our dozers. Great information. I have a buddy that called an sent me pictures of a whole tool box full of threading dies and when I seen them they were all hex dies. And he was mad because he was threading a head bolt on an engineer and broke the die. Thanks for sharing.
i remember being taught how to fix threads with nothing but a three square file so if you needed to repair and didnt have a hex die or chaser. also a really useful skill to have along with correct die use. Keep the great videos coming.
Dayum!!! I've been doing it wrong for years. This explains why I can't get a decently cut and centered thread even on 1/4 brass rod. So embarrassing...!!! As the saying goes, "A little knowledge is dangerous" Thank you, Adam.
That's absolutely the right thing to do. Break a borrowed tool? Buy a new one. 👍 That's what I consider basic respect for a friend or coworker. People who return a broken tool and just shrug it off are out of this world. No clue what goes on in their heads. 🤷🏻♂️
There are also split dies for chasing threads. You can put them on the good section then run them off the studs to clean up the threads. They have a tapered hex so pushing a socket over them forces the two halves together. And don't forget thread files. Great video. Shaper is getting real close there.
As a newbi these basic lessons ar so good. Thank you for passing on your knowledge onto us; Thought for the day: Smile and the world smiles with you.........
Two years of machine shop in high school, and invited to be a teacher's aid for 3 semesters after my first semester, and never knew. We had dies, and they were the round ones, but none of the students were allowed to use them. If you needed a 1/4" by 3/4" bold, they handed you a piece of hex and you had to make one and thread it on the lathe. Then you had to heat-treat it, but no fancy oven. A torch and watch for the color. :)
Button (or round) dies are split and have an adjustment screw to vary the spacing of the cutting portions in order to accommodate various kinds of work and/or materials, and the adjustment allows correction for die wear. Hexagonal dies can be used to cut new threads. Either can be used for rethreading
There are hex dies made for chasing threads. Lots of mechanics use them. But they are specifically made for that. The regular hex dies cut threads same as the round dies. Thanks for the great Video Adam!
Never knew there was a difference between hex and round dies. I also know I’ve never had much luck trying to cut new threads with any die without it going on crooked. I’ve always thought of dies primarily for chasing, and cutting new threads in a pinch. Very good information here! Thank you!
I seem to recall having a two piece bolt for chasing threads. You’d open it up and place it on a clean part of the threads, close it, and then run it over the bad threads until they were clean. It was size specific. We’d have to buy one for whatever size thread we were working on. Then I’d run a normal cutter back and forth with a cordless drill and socket just to really clean it up.
We took some cheap hex dies and cut them in half specifically for cleaning mushroom ends. Put them together on clean section, box wrench around them and back it out.
addendum... After chopping in half, used shims between the halves to compensate for the removed material . Maybe not critical but keeps the lil bastards from wandering around. 😉
Most of my shop experience waslearned in school in the 1960s & 1970s. I have been wanting to review some things. Now that I found you I subscribed. Those thread chasers were a new thing to me. Thanks. I look forward to our time together.
5:37 "no difference with a round die" True, unless it's a split die (like you showed!) in which case you can open it up a bit -- which might just let you slip it past the damaged end if it's not too boogered up, and then tighten it gently on the undamaged portion, checking there's still a tiny amount of slack, before winding it back off, to true up the damaged end.
I have been a machinist since 1975 and I did not know that a hex head threading die was used to chase threads and a round head was used to cut threads. I must have fallen a sleep during apprentice class when dies and die stocks were taught. Or if I knew it, I forgot it. Thanks Adam!
Keith Appleton showed that adjusting the round tapping die open a bit allowed him to tap the end of copper tubing without it sticking, galling and twisting on the first pass. Then he tightened it up to make a final pass. It might not have use on rod, but it helped on tube.
Fantastic tutorial as usual. I like your video and the way you explain. I am a boilermaker/welder, almost retired now, and inevitably I have worked with people of other trades and learned a ton of skills, (that is way us boilermakers we are called "jack "of all trades, where in realty we are only specialised in one, our on.), working with: motor mechanic's an fitters in the shop and on site where an experience fitter/mechanic really shows his skills under pressure and with limited equipment away from the comfort of the workshop, and I still have the obsession of learning from experts like you. Going back to the nut still not fitting smoothly, (even on a more stubborn situation of the one you showing us, I sow a fitter on site starting the nut and holding the shaft/rod further away from the nut and gently tappet it on a hard surface wile rotating it, by doing so the nut itself was reshaping the "not so damaged thread", back to the original shape. Of course I am not teaching you this, but only addition for most of us amateurs. Hope it would be of benefit. Thanks again for your splendid work.... Cosimo.
Thanks for sharing about the Buckingham 6103 thread chaser! That's a style I've never seen before, and I think it'll come in handy around my shop. Thanks to seeing it today, I went ahead and bought one.
Adam, I hope I'm not the 10th person to say this but a thread file is a really handy tool to have in the shop too. It would be cool if you could do a video with one of those. They work really well to repair a swelled thread especially if you can spin the part in the lathe because it is really easy to clean up a bad spot. A set of 4 good quality thread files that will do almost all common threads can be bought new on amazon for less than $50, that is a very affordable option for a lot of guys on a limited budget or just getting started. Best of all they don't take up a lot of space. Keep up the good work!
I'm 79, and as far back as I can remember, I have had tap and dies in my tool inventory. I just learned about the specific use for a round die and a hex die. This bit of information made me feel good about a decision I just recently made. I ordered a die from Amazon. I had a choice of a round M-27 die for $18, or a hex M-27 die for $30. Being "cheap" normally I would have bought the cheaper one. This time I chose the $30 hex die purely because it looked like I could use a tool on it! I have to repair the threads at the end of my van axle. I really like that thread chaser. I'll have to check the flea market for one. Thank you!
A chasing die is hexagonal, and a cutting die is round. TY Adam.My uncle restored a banged-up thread with a cold chisel & hammer when I was a kid on the farm!
NOPE - a thread chasing die is usually (but not always) Hex, however a cutting die can be Hex, Round, Square or whatever. The shape of the die is not what matters, it's the TYPE of die that matters.
I have hex dies and hex chasers, I also have some very old adjustable round dies and chasers . My thread dies have a sharp pointed cutting edge where the thread chasers edge is closer to 90 degrees to the thread surface. Chasers tend to push metal out of the way and dies tend to cut chips. Dies also seem to have a bit more "lead in" than chasers. Same seems true for taps....
You know something Adam, if you say it has been your "Rule of Thumb" then guess what, that means it becomes mine too cause youre the man in my book and reinventing the wheel is something I try to avoid. Keep the education going my friend.
Firstly, I have immense respect for you Abom, and this is about the only time I've disagreed with you. Tooth profile determines whether the die is a rethreading die, or a cutting die. It ALL has to do with hook angle. Can be hex or round. Adjustable will ONLY come in slit round or cone die (tapered, adjusted on a collet they are pretty uncommon). Hex was made for applications with limited clearance. Square dies are hard to find, and I've never seen one that is for cutting, only for rethreading. Plenty of tool manufacturers will note in their die catalogs whether it's for cutting or rethreading - and it's with few exceptions based off of that tooth profile.
Didn't even know these things existed. I've bought tap and die sets only for cleaning ("chasing") worn/rusted deformed threads internal/external. I've thought the hexagonal shape was a super new idea to stop the silly round dies from spinning in the tool that's supposed to hold them. Now to see if the hex and the other tool exist in Europe. Thanks a lot for the lesson. (I thought your arm was big, then I saw the size of your SPANNER!!!)
Very informative! Had not seen the chaser before. Very nice to be able to get back on good threads and use them to guide the recutting of mushroomed threads! Great video.
Great video. As a maintenance technician responsible for the installation, maintenance and repair in aerospace (NC and CNC), power plants, Light rail and Heavy rail electric trains over a period of 32 years required the frequent use of drilling, tapping and redressing damaged treads. I purchased my first standard and metric tap and die set in 1991. As a maintenance tech larger sizes of tap and dies were provided also by the company however I never knew that the round dies were for cutting new threads and the hex dies were for redressing damaged threads. I always used the rounded dies in cutting new threads simply because the holders were designed for round dies and the hex for cleaning up damaged threads simply because they fit well in socket sets and adjustable crescent wrenches. This is my first time on your TH-cam channel and I am happy I found your channel as you now have one more new subscriber. I now see why you have 345 subscribers. I am learning so much from you and keep these videos coming.
As a maintenance technician responsible for (blah blah) you should already know that the outside shape of the die has ABSOLUTELY NOTHING to do with what kind of die it is. Cutting dies can be ANY SHAPE. Round, square, hex, octagon, whatever. ANY SHAPE! Chasing / rethreading dies can be ANY SHAPE, but most commonly Hex because they are most commonly used by running them down a stud like a nut. Split dies are adjustable to allow cutting different classes (tolerances) of threads, and can be ANY SHAPE. The shape is only relevant to how you use the die, for example a Hex die can be used with standard tools whilst a round die must be used with a suitable holder.
Every time I watch a video, I learn something. When I work on anything with a thread or a bolt, I chase with a tap or die. Thanks for the knowledge on the difference between the two dies. I did happen to use a hex die to cut threads on a handle for a vise. I was nervous and it did work, but afterward didn't think it should be used for that purpose. Note to self! Adam has my pocket book on notice as I look for the Greenlee die handles and what not. I already bought some Starrett tools for my arsenal. Good information!
Great vid! I've seen one of my childhood mentors use a plumbers tubing cutter in an emergency on a rear axle pinion and it worked and I've had to do it once on a front half shaft on an 85 Chevy cavalier I literally had nothing but an old tool bag that came with the car and inside was plumbing tools including a pipe wrench and a rusted up pipe/tubing cutter and it worked perfectly Mr.Smitty was definitely watching out for me like a guardian angel it's almost like he knew I'd need to use that lil trick when I grew up, but in the end I doubt that cutter will ever cut pipe again but since then I always keep one handy along with a proper tap and die set with chasers!
I was taught the same thing about hex and round dies. I am so glad someone agrees with me. I can't count how many times I have had people argue with me that hex dies can cut new threads too. I always stood my ground but wondered.
Ive told this story many times over the years...It only sinks into the thick-headed know-it-all types when they stare like a deer in headlights at the hex die that just broke clean in half LOL...Hope this video educates and saves some pain for lots of non-believers
That simple piece of information, the difference between thread chasers and thread cutters is so hard to find. It’s particularly confusing because almost all consumer tap and die sets have hex dies. And since you use the taps to cut threads, absent any instructions to the contrary, one just assumes that the dies do the analogous job. I can’t tell you how many times I tried to cut threads and failed until I found out about the difference.
Thanks for a good video Adam but.... I was always taught that round split dies are for cutting threads all other dies without adjusting splits are for chasing threads. Many budjet tap & die sets come with unsplit round dies, in the smaller diamiters they will cut a thread but are not ideal
Good point on the hex dies for chasing, round for cutting. I went through seven 2 1/2" ultra fine thread hex dies from MSC last year trying to make a threaded shaft. I was blaming poor dies because the teeth kept chipping and it would cut for 1" of thread or so then start cross cutting thread. Went to a round one and did it one shot. I've been working with dies for going on 30 years and never knew this. I just thought the round dies were an older style, adjustable for custom thread diameters. Thank you for the tip!
From what I was taught, round (split) dies are intentionally made to be adjustable. Your die handle should have two set screws to hold the die (and also pinch in the thread size), and a dog point that runs down into the split (which enlarges the thread). By adjusting those three, you can tweek the thread in or out slightly to make a close fit to the mating part. Maybe not as pretty as a machined thread, but there are times when you can't get your work piece in the lathe. Yes, it's considered the 'poor mans' alternative, but some of us don't have the luxury or cost justification of a threading capable lathe. Split dies can be just as accurate if set up and used correctly.
That is what I always understood and just about all split dies sold here in the UK do not have the built in adjustment screw, but many things vary as to where you are in the world. As for threading on lathes, there are special die holders made which take segmented dies that open when the get to the correct length of thread, these are esential when cutting threads on auto lathes.
I'm in the U.K. also, and perhaps it has to do with the quality of the tool whether it has the adjustment or not. I use my late Dad's L.A.L. branded set for Imperial work, and when I need metric sizes I buy quality split dies that have the same adjustment facility that will fit the handles I have.
One of the reasons thread chasers are hex instead of round is that frequently they are used on threaded parts that are still installed in place and you cannot use a die handle due to the swing diameter. The hex allows for the use of a wrench or a socket which is probably what you used to remove the nut that was installed while the equipment was in operation. A good example of this scenario would be a damaged wheel stud on a vehicle.
My snap on thread chase set included files pitched to match threads, that could be run against the bolt to fix the threads enough to get a die on. I remember them being pretty dangerous to the untrained, but very useful to getting the die centered up.
Don't know how many times, after chasing or cutting threads, that I've used my fingers to quickly clean off the threads that had slivers of cut metal still on the bolt or stud and got one of those slivers in my thumb or finger. Taking the mental time to get a cloth has really paid off.
I use round dies to chase threads that are damaged on the end. Crank in the adjuster screw untill it is big enough to go over the end, then back the adjuster ou untill the die rides nice on an in damaged portion. Install handle and spin it off the end of the stud. Job done. Those chasers you have look pretty handy. If I had a set, I just might do it the way you do.
I have a pretty cool die set that’s pretty old... maybe the 20’s or 30’s. It has a round die handle and a round die insert, but it has two rectangular inserts that go in the round insert that have the thread cutters in them. So when a stud or bolt has a mushroomed end, I can take the two rectangular cutting inserts and line them up on the threads, assemble the holder and handle and then back the cutting die off the threads, essentially repairing them like a normal die would but in reverse. I don’t know if that was their intended purpose, but that’s how I have used that set and it has saved quite a few parts for me. I have no idea what they are called. They are basically a 2 piece die or a split die.
I was about to make some 3mm axles for my microphone storage box. For the hinges. I need to thread the ends for lock nuts so they stay securely in place. It was the right choice to watch your video about thread dies just to sanity check myself before doing anything foolish :D You never disappoint Adam ^_^
A good quality thread file will work for mushroom heads also if they are not in to bad a shape. As a machinist/equipment repair technician for over 5 decades it nice to see someone who knows their dies.
Good lesson. I didn't know that about hex dies either. When I cut a new thread on rod stock using a round die I find it easier to start if I use the adjustment to spread the die as far open as I can for the first pass, especially on tough steel, and then back it down to finish the thread. I use a chucking die holder in the tailstock of the lathe to start it straight.
I had always thought that a cutting die should have a conical lead in angle and a thread chaser would show less of an angle as the threads already exist. Perhaps Abom's dies just happen to be configured that way coincidentally, cutters are round and chasers are hex. At least I am confident that I have been figuring it out correctly all these years. Thanks fellows for all the good advice.
Yep, Abom's thread cutting dies just happen to be round. Lots of suppliers make thread cutters in Hex as well as square. The difference between cutters and chasers is that the chasing die is rolling the thread, not cutting it. So it doesn't have the sharp "teeth" that remove metal like a lathe tool.
Thanks Adam I have never heard about the difference between die types, good to know.The set I have has hex dies and I have cut threads with them but only on soft steel. It worked fine on this stuff.
Great teaching, I can't tell you how many people make videos and have zero knowledge or wrong information about this any so many other machining topics! Good to get old school tips and teaching from a pro. The tip that helped me with my project that I liked the best was to taper the end of the rod/shaft that you plan to make new threads on a new stock of rod or pin. Thank you
Except that he is providing WRONG INFORMATION. The shape of the die has zero relationship to whether it is for cutting or chasing. The cutting of a starting taper is common knowledge, that's not really a huge tip. How else would you get the tap to start straight?
Great video. Answered my question about round or hex dies when cutting new threads. (unfortunately I need to buy a set of round dies for the work that I do) I just found out on the LMS website, the difference, and you confirmed it. I also discovered that the Bukingham MFG tool that I have had for 20 years was not a pipe cutting tool, but a thread chaser!!! (no I didn't cut any pipes with it!) Spent many years in different machine shops, and no body told me that there was a difference. 30 yrs. of marginal threads will come to an end.... Thanks for your insight.
No, he is *WRONG*. There are numerous Hex thread-cutting dies from almost all suppliers. The distinction is that there are thread CUTTING dies and there are thread REFORMING dies... the outside shape of the die is not the way to determine which is which.
I prefer always to use a button die to cut threads but, have to use a hex die sometimes simply because I just don't have button threads for every thread and size. They do work quite well though OK for finishing off a single point thread just before it is complete. Chasers are super useful. Wish I had button dies for everything!
Hi Adam, I have three sets of tap and dies. They all have hex dies. One is a Matco, one is Ace= Both made by Hanson, that i bought 41 years ago From Matco Tools. My metric one is Snap-On, made in USA,not sure by whom. It has a Different pattern than hex. I really like them because you can use a deep socket,extension and ratchet for hard to reach places.Maybe these were bulit for us goofy mechanics. I do have hex thread chasers similar to yours. Most of all thanks for your Great teaching. I am learning alot from you. Thanks Alot!
Hi Adam, This video was so informative! Asusual, you provide complete and through instructions for professionals and amatuers like mysely. I continue to watch all of your videos! Thanks and God Bless you and Family. Max
I think you covered all that very well. In the UK we have the Buckingham thread restoring files which are a file with the correct TPI grooves cut in them, these are really handy when the first few threads are mangled, by using these you can dress the damaged areas out before using a die nut, the die nuts burst of course because they are unsupported by the die holder, as a split die is, I usually just use a triangular file to dress up a 60 deg thread. Chris B.
What a great shop talk!. Really enjoyed. There is always a thread someone has mangled on my work bench so this looked very familiar. Great Video thanks for sharing!
Hey its never boring to learn something new THANKS I NEVER NEW THAT AND IF I LEARN 1 THING A DAY I'M GOOD. SO THANX AND FOR THE TIME YOU TAKE TO TEACH US
Good video. You might talk about the different types of threads (Acme, UNC, NPT, etc.) and why different threads apply in different applications. Btw, many years ago, I threaded a monel shaft with a hex die. It cut well enough but produced an irregular thread, deeper on one side than the other, spiraling down the shaft. I guessed that using the wrench applied an uneven force and created the bad thread, but who knows. Thank you.
I just found your channel and I am hooked. I grew up in a machine shop in Saginaw, MI, and learn most of my machining by trial and error. I am 65 years old and I am convinced that I do many things wrong or the hard way! I will watch and learn. PS: I have a Buckingham thread chaser, thought I was the only one!
One thing you didn't cover is chasing threads on bolts and some studs. Most bolts and some studs have rolled threads. Rolling the threads is a cold forming process that adds strength to the bolt. Rolled threads have a rounded root as opposed to a cut thread that has a sharper vee root. Chasing a rolled thread, especially with a cutting die, cuts the root of the thread to the vee shape thus creating stress raisers and reducing the load capacity of the bolt by about 30%. Proper thread chasing dies only reform the thread sides without cutting the root of the thread.
Set from the factory? I thought the screw was to start with a light cut and then loosen the screw so the die could come together. Then if the bolt was still to tight, I'd go out another 1/4 turn or whatever was needed to get the tight but non binding fit. I really like the old little giant ones with the double inserts and the insert holders. I'm actually doing a bunch of 3/4-16 threads on #7 rebar(on the lathe) that will be the anchor bolts for my new shop. I'm doing about 75% on the lathe then chasing with the greenlee(?) die. I'm hoping that doing the bulk on the lathe will make the dies last longer and give a nice fit at the same time.
I dunno about the round/hexagonal thing... every tap & die set in my local (major chain) hardware stores is hexagonal. I can't believe they thought all their customers ever wanted to do was straighten out bolt threads? I have a set of Vermont American hexagonal dies. I was able to cut some 3/8"-16 threads on raw sock with no problem. Here's a tip: to get started, [A] grind the tip to taper it, [B] press the center firmly with your left palm to force it onto the rod, while turning with the right hand, until it bites.
Have been using a set of hex dies for several decades to cut threads on mild steel rods. Always wondered why sometimes the threads were horrible when made with those dies . Now I know. Another reason to go buy some new tools. Thanks for the info.
Abom i've been using dies wrong all this time. Dang it. I watch everyone of your videos. They're all education and fun to watch. Thanks again bud. FLO/GROWN HERE.
It may be the case in the USA that all hex dies are for re-threading or chasing. However in the UK and Australia a company called Goliath tools sells a range of high quality HSS hex dies (also called die nuts) specifically for cutting new threads. The main advantage of being hex shaped is they are able to re cut a damaged thread on say a stud in a tight spot with a standard wrench. (A full size die wrench may not have the room to be rotated 360deg) I have a full set myself. However they do not have an splitt slot , meaning they are not adjustable like the round ones. It also makes it harder to make a dedicated hex shaped tail-stock holder for them for the lathe. Other than that the Goliath dies are fine to cut new threads with. www.bordo.com.au/product-range/?view=productDetail&id=62021&catId=1646
@@Ben-sx5xb No not at all, I'm a carpenter wana be machinist. I never learned that round dies were meant for "cutting" and hex dies were meant for "chasing". Real question not sarcasm.
@@craigsudman4556 I had shop class for mechanical engineering and I can tell you chasers and regular dies have nothing to do with the outside shape. The T-shape (he calls it round) die is used for exposed threads (easily accessible). The hex shape is just a different style and some people use it for more confined places. At the end of the day just look at the shape of the teeth inside the die to tell if it's a chaser or not.
@@craigsudman4556 - Abom is completely wrong about the shape of dies. There are round, hex and square chasers, and there are round, hex and square cutting dies. The shape of the outside of the die relates more to how it is held during use, but NEVER dictates what kind of die it is.
I just did a test yesterday in CNC machining class and they showed a picture of those two dies. They wanted to know what one repairs threads and what one was to cut new threads. Thanks.
The round vs hex die rule generally holds true in the tool supplier brands. But in many of the consumer oriented and carbon steel brands, like Irwin and Craftsman, they do in fact have thread cutting dies in hex form, which makes them confusing if they get mixed in with one's other dies. Chasing dies aren't designed to cut, but as more of a forming tool to reshape the existing threads. A regular die can just cut the damaged material away and leave you with no thread in that spot. The difference is clear if you look closely enough. Those Buckingham chasers are cool. Haven't seen that style.
Thanks for the advise , I just bought a hold set hex nuts whit the drive handle both imperial and metric sizes , I guess I will have to buy a few Round dies ...
I don’t know much About Taps & Dies.Fortunately my Town has a Hardware Store that has been in business since the late 1800s and has practically anything you would need in hardware. I thought I needed a left hand thread Die. I went to this Hardware Store to purchase one. This Hardware Store has a lot of very knowledgeable Employees that have been working there for 30 years and more. I asked for help in finding the Die at the check out counter and the Lady at the counter called for a employee that is very knowledgeable about Taps and Dies. When I told him I Needed a left hand thread Die. He asked me whether I was threading a piece of stock or chasing a thread. I told him I was chasing a thread. He gave me a Hex Die and told me that it should be used only for chasing threads and not cutting threads. When I asked him why this Die was not for threading , he said because it was designed for chasing threads and will most likely break if I would use it to cut threads.What was really great, was this Hardware Store had the exact same Left Hand Threaded Bolt like the one I needed to chase the threads on. The Bolt was more expensive than the Thread Chasing Die. So I purchased the Die.
That was awesome, Adam. When I needed to cut a bolt, I would put a nut on before I cut and then back the nut off. Poor man's method but it worked. Then just file the end. Did I say poor "man"? I did this when I was 12. Not to put down what you are doing here, as this is the proper and accurate way, not to mention my method didn't work with an existing mushroom on a dedicated length bolt or stud. Love your videos Adam and say Hi to Tony! You guys are great! Congratulations on your independence. You are now the Boss! You will succeed. Thank You, Adam.
I have heard this for years but both my tpi and metric sets are hex and were sold as thread cutting. And I have cut many a thread with them. 45 years ago when purchased I hadn't heard the difference so just went on using them(hex) for both. Still do. Not disagreeing but saying what has worked for years for me.
i bought a tap and die set sold as cutting, it couldnt cut a noodle, ! they do cut, you dont have the advantage of the long arm wrench to help keep it level
Jusb1066 mine came with a hex die wrench and keeping level was no problem. In later years I have used some round dies and haven't seen any better results. The hex I have were from Sears back in the day when their tools were considered good. Today I would buy round but my hex have worked fine.
ahh ive not seen a hex die wrench, my hex dies are HSS and thus inside are the same as a regular die, but i dont have the hex wrench to help get and maintain its level, but i have used it to cut a virgin thread, as i dont have anything else and i rarely need to cut new threads, (well apart from a super cheap set made of carbon steel, they arent split dies but round, and cant cut toffee anyway, but got a single job done back in the day)
I was under impression that the actual shape doesn't matter - the hex is just geared towards people that need to use a wrench to cut the thread - such as tradesmen. I.e. the Hex and Round if both made to cut thread are... thread cutting dies. Now there is something called re-threading die - which happen to be hex - that is used for "re-threading" only. The way it works is it doesn't cut a thread but moves the metal around - thus it doesn't actually remove much metal. If you re-thread with thread cutting die you remove extra metal and weaken the thread. Now 99% of people re-thread with a thread cutting die as they don't care that much about thread strength - but when it is critical you need to use re-threading die ... the also make re-threading taps.
@@daviddale4206 - Thread cutting dies can be ANY SHAPE. Thread chasing / reforming dies can be ANY SHAPE. Most chasing NUTS are hex, so they can be used with a normal spanner.
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As a non-machinist I learned why there are 2 different dies for chasing threads properly. Years ago I bought a set of round and hexagonal couldn’t tell why they were different until now. Even at 70 years old it is fun learning new things. Thanks Adam.
One thing I've learned about master machinists. They always know what the right tool for the job is and they always use it. I see so many new tools on your channel that I didn't even know were the right tool for the job.
Appreciate you mentioning and using safety glasses when demonstrating this. Way to many TH-camrs fail to emphasize and teach the importance of good safety habits on their channels. Having a Dr. operate on the sclera part of you eye (white part), while awake, with only local anesthesia injected into the eyeball, to remove embeded foreign debris, is no joke! Doctor said that he performs this procedure a couple times a month! Now ask me how I know this. Keep up the good work Adam! Thanks.
I have had metal, and the resulting rust stain drilled out of my eye twice. Both times while wearing glasses when I should have had a face shield. It's about zero fun.
Hi Adam,
The split dies have to be adjustable to allow for wear. Also, it is not that they are set up to size by the manufacturer; it is the handle that allows different degrees of expansion because of the fit tolerance of the hole that the die sits in.
If you are threading a very hard material then tighten the screw opposite the split to open up the die a bit, cut an oversize thread, then loosen that screw and tighten the closer screws to cut a deeper thread, thereby saving your die doing all the work in one go and wearing out faster.
If you have to match a worn threaded hole you can open the die to make the thread a bit bigger, or, to match a worn tap or bolt/stud, close the die up to make it a bit smaller.
It is the handle that limits the expansion of the die stopping it from breaking which is what your friend did with the die nut (sorry, I am English; we use split die and die nut to describe them). Never use a split die without a handle, it will guarantee to break.
Keep up the good work
Andy
Came here to say this, but you beat me to it.
Old school industrial maintenance man here, and I'm pretty up on all the "things" related to stuff like this, but I had never thought about the preferential uses of hex vs round dies.
Makes a hella lot of sense, though, and explains many of my cuss fests in trying to thread even the most basic steel rod with hex dies.
Even after 30 years of doing this stuff , I'm always thrilled to learn new things like this.
Thank you very much for stuff like this!
There are some really good people in this world and this guy is definitely one of those. So grateful he takes this time out of his busy day to explain the difference between thread cutting dies and thread chasing dies. He saved me a big headache.
Something you could also mention Adam is to pay attention with any rethreading die which side of the die has a chamfer, that must always face towards the threads so the die will begin to cut gradually. Great videos!
Yup, but if you need to thread close to a shoulder, having done it your way, then turn the diebutton around and do it again.
Great video Adam, I reckon probably 75% of people did not know the difference between the two types, I am in the 75%....Every day a school day! Thank you!
Same for me. I never knew the difference. It's nice to learn something new :)
Adam, you offer the best of what YT has to offer - I learn something in every one of your videos. That's the pinnacle of content production. Thanks. Please keep them coming!
Hi Adam, it's always nice to learn something new! I did not know the diff between round & hex, now I do!! Thanks, I do enjoy Shop Talk! Keep 'em coming!
Thanks for the info and the video.
You have an uncommon friend, usually one gets the broken tool back with a "I owe you a new one" and that's the end of it as if the acknloedgement of the debt is alll that's really required.
I long ago stopped loaning tools out to anyone that's not my father. (He's the sole exception; if he broke a screwdriver he'd feel so bad he'd try to buy me a new set.)
I learned something new today! For 40+ years I've been using hex dies to try to cut new threads in a rod with poor results usually. Being a diesel mechanic, most tools were purchased off of the tool trucks like Snap-On or Mac. They all sell tap and dies sets, and they have hex dies in them. No where do the tell you it's for thread repair not cutting virgin threads! The tool jockeys just want to sell you something. Adam you rock!
knew about round dies made for cutting, but glad you straightened out me on the hex dies,I've got dads old tools and they included those hex so now i know only to use those to chase.Thanks Adam
My grandpa was a machinist, he died in '79 when I was just few months old. Even though I don't remember him I was always impressed by his work, machines, tools and workshop he left. He even made a small tractor for a farm he owned. I wish I could learn craft from him...
Tomasz Sz sorry to hear that about your grandpa, but that's the way it is with good people, they left a lot of good stuff to be learned and remembered, I also lost my father when I was 13 but at 41 I keep learning from stuff and tools he left.
Hi Adam, correct in all cases, the round/adjustable die is to allow for thread size based on material difference, pinch it in for tougher materials, and also for a smaller size if the thread is to be plated. You can get oversize taps when the female thread is to be plated, chassis for example. Great informative video as always.
My father taught me the same. He also showed me that the round dies with the adjustment screw in was used to step it down as you thread. I've done it several times on head bolts on our dozers. Great information. I have a buddy that called an sent me pictures of a whole tool box full of threading dies and when I seen them they were all hex dies. And he was mad because he was threading a head bolt on an engineer and broke the die. Thanks for sharing.
i remember being taught how to fix threads with nothing but a three square file so if you needed to repair and didnt have a hex die or chaser. also a really useful skill to have along with correct die use. Keep the great videos coming.
Dayum!!! I've been doing it wrong for years. This explains why I can't get a decently cut and centered thread even on 1/4 brass rod. So embarrassing...!!! As the saying goes, "A little knowledge is dangerous" Thank you, Adam.
That's absolutely the right thing to do. Break a borrowed tool? Buy a new one. 👍 That's what I consider basic respect for a friend or coworker. People who return a broken tool and just shrug it off are out of this world. No clue what goes on in their heads. 🤷🏻♂️
There are also split dies for chasing threads. You can put them on the good section then run them off the studs to clean up the threads. They have a tapered hex so pushing a socket over them forces the two halves together. And don't forget thread files. Great video. Shaper is getting real close there.
As a newbi these basic lessons ar so good. Thank you for passing on your knowledge onto us;
Thought for the day: Smile and the world smiles with you.........
Two years of machine shop in high school, and invited to be a teacher's aid for 3 semesters after my first semester, and never knew. We had dies, and they were the round ones, but none of the students were allowed to use them. If you needed a 1/4" by 3/4" bold, they handed you a piece of hex and you had to make one and thread it on the lathe. Then you had to heat-treat it, but no fancy oven. A torch and watch for the color. :)
You seem proud, yet it's obvious to everyone reading that your "schooling" was severely lacking in practical aspects.
Button (or round) dies are split and have an adjustment screw to vary the spacing of the cutting portions in order to accommodate various kinds of work and/or materials, and the adjustment allows correction for die wear.
Hexagonal dies can be used to cut new threads. Either can be used for rethreading
There are hex dies made for chasing threads. Lots of mechanics use them. But they are specifically made for that. The regular hex dies cut threads same as the round dies. Thanks for the great Video Adam!
Never knew there was a difference between hex and round dies. I also know I’ve never had much luck trying to cut new threads with any die without it going on crooked. I’ve always thought of dies primarily for chasing, and cutting new threads in a pinch. Very good information here! Thank you!
I seem to recall having a two piece bolt for chasing threads. You’d open it up and place it on a clean part of the threads, close it, and then run it over the bad threads until they were clean. It was size specific. We’d have to buy one for whatever size thread we were working on.
Then I’d run a normal cutter back and forth with a cordless drill and socket just to really clean it up.
We took some cheap hex dies and cut them in half specifically for cleaning mushroom ends. Put them together on clean section, box wrench around them and back it out.
addendum... After chopping in half, used shims between the halves to compensate for the removed material . Maybe not critical but keeps the lil bastards from wandering around. 😉
X2 on this method which has always worked well if you can spare a die to cut on half :). Example at fj40toolbox.com/index.php/projects/thread-repair
I look forward to the SNS and Abom Adventures and now the Shop Talk videos. Great content and done the Abom way!
Most of my shop experience waslearned in school in the 1960s & 1970s. I have been wanting to review some things. Now that I found you I subscribed.
Those thread chasers were a new thing to me.
Thanks. I look forward to our time together.
5:37 "no difference with a round die" True, unless it's a split die (like you showed!) in which case you can open it up a bit -- which might just let you slip it past the damaged end if it's not too boogered up, and then tighten it gently on the undamaged portion, checking there's still a tiny amount of slack, before winding it back off, to true up the damaged end.
I have been a machinist since 1975 and I did not know that a hex head threading die was used to chase threads and a round head was used to cut threads. I must have fallen a sleep during apprentice class when dies and die stocks were taught. Or if I knew it, I forgot it. Thanks Adam!
Keith Appleton showed that adjusting the round tapping die open a bit allowed him to tap the end of copper tubing without it sticking, galling and twisting on the first pass. Then he tightened it up to make a final pass. It might not have use on rod, but it helped on tube.
Fantastic tutorial as usual. I like your video and the way you explain. I am a boilermaker/welder, almost retired now, and inevitably I have worked with people of other trades and learned a ton of skills, (that is way us boilermakers we are called "jack "of all trades, where in realty we are only specialised in one, our on.), working with: motor mechanic's an fitters in the shop and on site where an experience fitter/mechanic really shows his skills under pressure and with limited equipment away from the comfort of the workshop, and I still have the obsession of learning from experts like you. Going back to the nut still not fitting smoothly, (even on a more stubborn situation of the one you showing us, I sow a fitter on site starting the nut and holding the shaft/rod further away from the nut and gently tappet it on a hard surface wile rotating it, by doing so the nut itself was reshaping the "not so damaged thread", back to the original shape. Of course I am not teaching you this, but only addition for most of us amateurs. Hope it would be of benefit. Thanks again for your splendid work.... Cosimo.
Thanks for sharing about the Buckingham 6103 thread chaser! That's a style I've never seen before, and I think it'll come in handy around my shop. Thanks to seeing it today, I went ahead and bought one.
Adam, I hope I'm not the 10th person to say this but a thread file is a really handy tool to have in the shop too. It would be cool if you could do a video with one of those. They work really well to repair a swelled thread especially if you can spin the part in the lathe because it is really easy to clean up a bad spot. A set of 4 good quality thread files that will do almost all common threads can be bought new on amazon for less than $50, that is a very affordable option for a lot of guys on a limited budget or just getting started. Best of all they don't take up a lot of space. Keep up the good work!
I'm 79, and as far back as I can remember, I have had tap and dies in my tool inventory. I just learned about the specific use for a round die and a hex die. This bit of information made me feel good about a decision I just recently made. I ordered a die from Amazon. I had a choice of a round M-27 die for $18, or a hex M-27 die for $30. Being "cheap" normally I would have bought the cheaper one. This time I chose the $30 hex die purely because it looked like I could use a tool on it! I have to repair the threads at the end of my van axle. I really like that thread chaser. I'll have to check the flea market for one. Thank you!
A chasing die is hexagonal, and a cutting die is round. TY Adam.My uncle restored a banged-up thread with a cold chisel & hammer when I was a kid on the farm!
NOPE - a thread chasing die is usually (but not always) Hex, however a cutting die can be Hex, Round, Square or whatever. The shape of the die is not what matters, it's the TYPE of die that matters.
I have gone for years not knowing about the difference between hex and round dies. Thank you for sharing that little fact!
jup first I have heard of that in all my years, but I love his thread chaser never seen that one before or I would have had one or two, in my tool box
I have hex dies and hex chasers, I also have some very old adjustable round dies and chasers . My thread dies have a sharp pointed cutting edge where the thread chasers edge is closer to 90 degrees to the thread surface. Chasers tend to push metal out of the way and dies tend to cut chips. Dies also seem to have a bit more "lead in" than chasers. Same seems true for taps....
You know something Adam, if you say it has been your "Rule of Thumb" then guess what, that means it becomes mine too cause youre the man in my book and reinventing the wheel is something I try to avoid. Keep the education going my friend.
Firstly, I have immense respect for you Abom, and this is about the only time I've disagreed with you.
Tooth profile determines whether the die is a rethreading die, or a cutting die. It ALL has to do with hook angle. Can be hex or round. Adjustable will ONLY come in slit round or cone die (tapered, adjusted on a collet they are pretty uncommon). Hex was made for applications with limited clearance. Square dies are hard to find, and I've never seen one that is for cutting, only for rethreading.
Plenty of tool manufacturers will note in their die catalogs whether it's for cutting or rethreading - and it's with few exceptions based off of that tooth profile.
Great video!! I never knew the difference between round and hex dies. And those thread chasers are cool!!
Didn't even know these things existed. I've bought tap and die sets only for cleaning ("chasing") worn/rusted deformed threads internal/external. I've thought the hexagonal shape was a super new idea to stop the silly round dies from spinning in the tool that's supposed to hold them. Now to see if the hex and the other tool exist in Europe. Thanks a lot for the lesson. (I thought your arm was big, then I saw the size of your SPANNER!!!)
Excellent - I never knew the difference between round and hex. Learning much by watching your videos. Thanks for posting.
I always thought the round ones were older then the hexes.. Now I know...
Very informative! Had not seen the chaser before. Very nice to be able to get back on good threads and use them to guide the recutting of mushroomed threads! Great video.
Great video. As a maintenance technician responsible for the installation, maintenance and repair in aerospace (NC and CNC), power plants, Light rail and Heavy rail electric trains over a period of 32 years required the frequent use of drilling, tapping and redressing damaged treads. I purchased my first standard and metric tap and die set in 1991. As a maintenance tech larger sizes of tap and dies were provided also by the company however I never knew that the round dies were for cutting new threads and the hex dies were for redressing damaged threads. I always used the rounded dies in cutting new threads simply because the holders were designed for round dies and the hex for cleaning up damaged threads simply because they fit well in socket sets and adjustable crescent wrenches. This is my first time on your TH-cam channel and I am happy I found your channel as you now have one more new subscriber. I now see why you have 345 subscribers. I am learning so much from you and keep these videos coming.
As a maintenance technician responsible for (blah blah) you should already know that the outside shape of the die has ABSOLUTELY NOTHING to do with what kind of die it is.
Cutting dies can be ANY SHAPE. Round, square, hex, octagon, whatever. ANY SHAPE!
Chasing / rethreading dies can be ANY SHAPE, but most commonly Hex because they are most commonly used by running them down a stud like a nut.
Split dies are adjustable to allow cutting different classes (tolerances) of threads, and can be ANY SHAPE.
The shape is only relevant to how you use the die, for example a Hex die can be used with standard tools whilst a round die must be used with a suitable holder.
Every time I watch a video, I learn something. When I work on anything with a thread or a bolt, I chase with a tap or die. Thanks for the knowledge on the difference between the two dies. I did happen to use a hex die to cut threads on a handle for a vise. I was nervous and it did work, but afterward didn't think it should be used for that purpose. Note to self! Adam has my pocket book on notice as I look for the Greenlee die handles and what not. I already bought some Starrett tools for my arsenal. Good information!
Great vid! I've seen one of my childhood mentors use a plumbers tubing cutter in an emergency on a rear axle pinion and it worked and I've had to do it once on a front half shaft on an 85 Chevy cavalier I literally had nothing but an old tool bag that came with the car and inside was plumbing tools including a pipe wrench and a rusted up pipe/tubing cutter and it worked perfectly Mr.Smitty was definitely watching out for me like a guardian angel it's almost like he knew I'd need to use that lil trick when I grew up, but in the end I doubt that cutter will ever cut pipe again but since then I always keep one handy along with a proper tap and die set with chasers!
Thanks again Adam! I keep learning more each time I view your videos - you are a an great teacher and machinist.
I was taught the same thing about hex and round dies. I am so glad someone agrees with me. I can't count how many times I have had people argue with me that hex dies can cut new threads too. I always stood my ground but wondered.
Ive told this story many times over the years...It only sinks into the thick-headed know-it-all types when they stare like a deer in headlights at the hex die that just broke clean in half LOL...Hope this video educates and saves some pain for lots of non-believers
That simple piece of information, the difference between thread chasers and thread cutters is so hard to find. It’s particularly confusing because almost all consumer tap and die sets have hex dies. And since you use the taps to cut threads, absent any instructions to the contrary, one just assumes that the dies do the analogous job. I can’t tell you how many times I tried to cut threads and failed until I found out about the difference.
Thanks for a good video Adam but....
I was always taught that round split dies are for cutting threads all other dies without adjusting splits are for chasing threads.
Many budjet tap & die sets come with unsplit round dies, in the smaller diamiters they will cut a thread but are not ideal
Good point on the hex dies for chasing, round for cutting. I went through seven 2 1/2" ultra fine thread hex dies from MSC last year trying to make a threaded shaft. I was blaming poor dies because the teeth kept chipping and it would cut for 1" of thread or so then start cross cutting thread. Went to a round one and did it one shot. I've been working with dies for going on 30 years and never knew this. I just thought the round dies were an older style, adjustable for custom thread diameters.
Thank you for the tip!
From what I was taught, round (split) dies are intentionally made to be adjustable. Your die handle should have two set screws to hold the die (and also pinch in the thread size), and a dog point that runs down into the split (which enlarges the thread). By adjusting those three, you can tweek the thread in or out slightly to make a close fit to the mating part. Maybe not as pretty as a machined thread, but there are times when you can't get your work piece in the lathe. Yes, it's considered the 'poor mans' alternative, but some of us don't have the luxury or cost justification of a threading capable lathe. Split dies can be just as accurate if set up and used correctly.
That is what I always understood and just about all split dies sold here in the UK do not have the built in adjustment screw, but many things vary as to where you are in the world. As for threading on lathes, there are special die holders made which take segmented dies that open when the get to the correct length of thread, these are esential when cutting threads on auto lathes.
I'm in the U.K. also, and perhaps it has to do with the quality of the tool whether it has the adjustment or not. I use my late Dad's L.A.L. branded set for Imperial work, and when I need metric sizes I buy quality split dies that have the same adjustment facility that will fit the handles I have.
The diestock has the centre screw and any diestock sold here in the UK has it, as well as the 2 holding screws
One of the reasons thread chasers are hex instead of round is that frequently they are used on threaded parts that are still installed in place and you cannot use a die handle due to the swing diameter. The hex allows for the use of a wrench or a socket which is probably what you used to remove the nut that was installed while the equipment was in operation. A good example of this scenario would be a damaged wheel stud on a vehicle.
My snap on thread chase set included files pitched to match threads, that could be run against the bolt to fix the threads enough to get a die on. I remember them being pretty dangerous to the untrained, but very useful to getting the die centered up.
Don't know how many times, after chasing or cutting threads, that I've used my fingers to quickly clean off the threads that had slivers of cut metal still on the bolt or stud and got one of those slivers in my thumb or finger. Taking the mental time to get a cloth has really paid off.
I use round dies to chase threads that are damaged on the end. Crank in the adjuster screw untill it is big enough to go over the end, then back the adjuster ou untill the die rides nice on an in damaged portion. Install handle and spin it off the end of the stud. Job done.
Those chasers you have look pretty handy. If I had a set, I just might do it the way you do.
I never knew the difference between hex and round dies until today. Thanks!
I have a pretty cool die set that’s pretty old... maybe the 20’s or 30’s. It has a round die handle and a round die insert, but it has two rectangular inserts that go in the round insert that have the thread cutters in them. So when a stud or bolt has a mushroomed end, I can take the two rectangular cutting inserts and line them up on the threads, assemble the holder and handle and then back the cutting die off the threads, essentially repairing them like a normal die would but in reverse. I don’t know if that was their intended purpose, but that’s how I have used that set and it has saved quite a few parts for me. I have no idea what they are called. They are basically a 2 piece die or a split die.
Those split dies seem really convenient, they were pretty expensive last I checked though..
I was about to make some 3mm axles for my microphone storage box. For the hinges. I need to thread the ends for lock nuts so they stay securely in place. It was the right choice to watch your video about thread dies just to sanity check myself before doing anything foolish :D
You never disappoint Adam ^_^
A good quality thread file will work for mushroom heads also if they are not in to bad a shape. As a machinist/equipment repair technician for over 5 decades it nice to see someone who knows their dies.
Good lesson. I didn't know that about hex dies either. When I cut a new thread on rod stock using a round die I find it easier to start if I use the adjustment to spread the die as far open as I can for the first pass, especially on tough steel, and then back it down to finish the thread. I use a chucking die holder in the tailstock of the lathe to start it straight.
Great video, I never realized that there was any significance to the shape of the dies but it makes sense now!
I had always thought that a cutting die should have a conical lead in angle and a thread chaser would show less of an angle as the threads already exist. Perhaps Abom's dies just happen to be configured that way coincidentally, cutters are round and chasers are hex. At least I am confident that I have been figuring it out correctly all these years. Thanks fellows for all the good advice.
Yep, Abom's thread cutting dies just happen to be round. Lots of suppliers make thread cutters in Hex as well as square. The difference between cutters and chasers is that the chasing die is rolling the thread, not cutting it. So it doesn't have the sharp "teeth" that remove metal like a lathe tool.
Thanks Adam I have never heard about the difference between die types, good to know.The set I have has hex dies and I have cut threads with them but only on soft steel. It worked fine on this stuff.
Great teaching, I can't tell you how many people make videos and have zero knowledge or wrong information about this any so many other machining topics! Good to get old school tips and teaching from a pro. The tip that helped me with my project that I liked the best was to taper the end of the rod/shaft that you plan to make new threads on a new stock of rod or pin. Thank you
Except that he is providing WRONG INFORMATION. The shape of the die has zero relationship to whether it is for cutting or chasing.
The cutting of a starting taper is common knowledge, that's not really a huge tip. How else would you get the tap to start straight?
Great video. Answered my question about round or hex dies when cutting new threads. (unfortunately I need to buy a set of round dies for the work that I do) I just found out on the LMS website, the difference, and you confirmed it. I also discovered that the Bukingham MFG tool that I have had for 20 years was not a pipe cutting tool, but a thread chaser!!! (no I didn't cut any pipes with it!) Spent many years in different machine shops, and no body told me that there was a difference. 30 yrs. of marginal threads will come to an end.... Thanks for your insight.
Hi after 30 years of machine works you are correct of the different dies for the right job
No, he is *WRONG*. There are numerous Hex thread-cutting dies from almost all suppliers. The distinction is that there are thread CUTTING dies and there are thread REFORMING dies... the outside shape of the die is not the way to determine which is which.
I prefer always to use a button die to cut threads but, have to use a hex die sometimes simply because I just don't have button threads for every thread and size. They do work quite well though OK for finishing off a single point thread just before it is complete. Chasers are super useful.
Wish I had button dies for everything!
Hi Adam, I have three sets of tap and dies. They all have hex dies. One is a Matco, one is Ace= Both made by Hanson, that i bought 41 years ago From Matco Tools. My metric one is Snap-On, made in USA,not sure by whom. It has a Different pattern than hex. I really like them because you can use a deep socket,extension and ratchet for hard to reach places.Maybe these were bulit for us goofy mechanics. I do have hex thread chasers similar to yours. Most of all thanks for your Great teaching. I am learning alot from you. Thanks Alot!
Hi Adam, This video was so informative! Asusual, you provide complete and through instructions for professionals and amatuers like mysely. I continue to watch all of your videos! Thanks and God Bless you and Family. Max
I think you covered all that very well. In the UK we have the Buckingham thread restoring files which are a file with the correct TPI grooves cut in them, these are really handy when the first few threads are mangled, by using these you can dress the damaged areas out before using a die nut, the die nuts burst of course because they are unsupported by the die holder, as a split die is, I usually just use a triangular file to dress up a 60 deg thread. Chris B.
What a great shop talk!. Really enjoyed. There is always a thread someone has mangled on my work bench so this looked very familiar. Great Video thanks for sharing!
Kristofor Gorham I think he has access to quality Russian tooling
Hey its never boring to learn something new THANKS I NEVER NEW THAT AND IF I LEARN 1 THING A DAY I'M GOOD. SO THANX AND FOR THE TIME YOU TAKE TO TEACH US
There exists a thread repair tool that employs rollers to swage the thread. Works really well and can be started anywhere on the thread.
Good video. You might talk about the different types of threads (Acme, UNC, NPT, etc.) and why different threads apply in different applications.
Btw, many years ago, I threaded a monel shaft with a hex die. It cut well enough but produced an irregular thread, deeper on one side than the other, spiraling down the shaft. I guessed that using the wrench applied an uneven force and created the bad thread, but who knows. Thank you.
Thank-you Adam, being 64 yrs old I didn't know this about Tap's and die's.
I just found your channel and I am hooked. I grew up in a machine shop in Saginaw, MI, and learn most of my machining by trial and error. I am 65 years old and I am convinced that I do many things wrong or the hard way! I will watch and learn. PS: I have a Buckingham thread chaser, thought I was the only one!
One thing you didn't cover is chasing threads on bolts and some studs. Most bolts and some studs have rolled threads. Rolling the threads is a cold forming process that adds strength to the bolt. Rolled threads have a rounded root as opposed to a cut thread that has a sharper vee root. Chasing a rolled thread, especially with a cutting die, cuts the root of the thread to the vee shape thus creating stress raisers and reducing the load capacity of the bolt by about 30%. Proper thread chasing dies only reform the thread sides without cutting the root of the thread.
Set from the factory? I thought the screw was to start with a light cut and then loosen the screw so the die could come together. Then if the bolt was still to tight, I'd go out another 1/4 turn or whatever was needed to get the tight but non binding fit. I really like the old little giant ones with the double inserts and the insert holders. I'm actually doing a bunch of 3/4-16 threads on #7 rebar(on the lathe) that will be the anchor bolts for my new shop. I'm doing about 75% on the lathe then chasing with the greenlee(?) die. I'm hoping that doing the bulk on the lathe will make the dies last longer and give a nice fit at the same time.
You shouldn't have to fiddle with that screw. You want to grab the die you need and do the job, not mess around with adjusting it to the right pitch.
Abom79 don't get me wrong, I wasn't doubting. I was just always worried I'd break it and didn't know any better.
I dunno about the round/hexagonal thing... every tap & die set in my local (major chain) hardware stores is hexagonal. I can't believe they thought all their customers ever wanted to do was straighten out bolt threads?
I have a set of Vermont American hexagonal dies. I was able to cut some 3/8"-16 threads on raw sock with no problem.
Here's a tip: to get started, [A] grind the tip to taper it, [B] press the center firmly with your left palm to force it onto the rod, while turning with the right hand, until it bites.
I just did a 5/8 rod to 5 inches of thread -- hex die, lots of oil, huge wrench, and slow pace. Came out great!
I was disappointed by the title of this video. The threads clearly survived.
Have been using a set of hex dies for several decades to cut threads on mild steel rods. Always wondered why sometimes the threads were horrible when made with those dies . Now I know. Another reason to go buy some new tools. Thanks for the info.
Abom i've been using dies wrong all this time. Dang it. I watch everyone of your videos. They're all education and fun to watch. Thanks again bud. FLO/GROWN HERE.
It may be the case in the USA that all hex dies are for re-threading or chasing. However in the UK and Australia a company called Goliath tools sells a range of high quality HSS hex dies (also called die nuts) specifically for cutting new threads.
The main advantage of being hex shaped is they are able to re cut a damaged thread on say a stud in a tight spot with a standard wrench. (A full size die wrench may not have the room to be rotated 360deg)
I have a full set myself. However they do not have an splitt slot , meaning they are not adjustable like the round ones.
It also makes it harder to make a dedicated hex shaped tail-stock holder for them for the lathe. Other than that the Goliath dies are fine to cut new threads with.
www.bordo.com.au/product-range/?view=productDetail&id=62021&catId=1646
There may be other styles I'm not aware of.
Ah...always wondered how one was able to tell the difference between a "cutting" and "chasing" die. Thank you Abom, great video, thumbs up.
I can sense sarcasm hahahahah
@@Ben-sx5xb No not at all, I'm a carpenter wana be machinist. I never learned that round dies were meant for "cutting" and hex dies were meant for "chasing". Real question not sarcasm.
@@craigsudman4556 I had shop class for mechanical engineering and I can tell you chasers and regular dies have nothing to do with the outside shape. The T-shape (he calls it round) die is used for exposed threads (easily accessible). The hex shape is just a different style and some people use it for more confined places. At the end of the day just look at the shape of the teeth inside the die to tell if it's a chaser or not.
@@craigsudman4556 - Abom is completely wrong about the shape of dies. There are round, hex and square chasers, and there are round, hex and square cutting dies. The shape of the outside of the die relates more to how it is held during use, but NEVER dictates what kind of die it is.
I just did a test yesterday in CNC machining class and they showed a picture of those two dies.
They wanted to know what one repairs threads and what one was to cut new threads.
Thanks.
LOL, if you used the bullshit in this video, then you would have got that question wrong.
The round vs hex die rule generally holds true in the tool supplier brands. But in many of the consumer oriented and carbon steel brands, like Irwin and Craftsman, they do in fact have thread cutting dies in hex form, which makes them confusing if they get mixed in with one's other dies. Chasing dies aren't designed to cut, but as more of a forming tool to reshape the existing threads. A regular die can just cut the damaged material away and leave you with no thread in that spot. The difference is clear if you look closely enough.
Those Buckingham chasers are cool. Haven't seen that style.
Thanks Adam. Now I know why I have had such a hard time threading with my Hex Die's.
Thanks for the advise , I just bought a hold set hex nuts whit the drive handle both imperial and metric sizes , I guess I will have to buy a few Round dies ...
I don’t know much About Taps & Dies.Fortunately my Town has a Hardware Store that has been in business since the late 1800s and has practically anything you would need in hardware. I thought I needed a left hand thread Die. I went to this Hardware Store to purchase one. This Hardware Store has a lot of very knowledgeable Employees that have been working there for 30 years and more. I asked for help in finding the Die at the check out counter and the Lady at the counter called for a employee that is very knowledgeable about Taps and Dies. When I told him I Needed a left hand thread Die. He asked me whether I was threading a piece of stock or chasing a thread. I told him I was chasing a thread. He gave me a Hex Die and told me that it should be used only for chasing threads and not cutting threads. When I asked him why this Die was not for threading , he said because it was designed for chasing threads and will most likely break if I would use it to cut threads.What was really great, was this Hardware Store had the exact same Left Hand Threaded Bolt like the one I needed to chase the threads on. The Bolt was more expensive than the Thread Chasing Die. So I purchased the Die.
I love old hardware stores like that. We have a couple in town also.
That was awesome, Adam. When I needed to cut a bolt, I would put a nut on before I cut and then back the nut off. Poor man's method but it worked. Then just file the end. Did I say poor "man"? I did this when I was 12. Not to put down what you are doing here, as this is the proper and accurate way, not to mention my method didn't work with an existing mushroom on a dedicated length bolt or stud. Love your videos Adam and say Hi to Tony! You guys are great! Congratulations on your independence. You are now the Boss! You will succeed. Thank You, Adam.
A lot of very good information! I’m just learning about tap and dies. Awesome video!
Thread files work nice to clean up existing threads
Had a nice set of thread files they worked well
Agreed!
Never knew about hex and round dies,
Thanks 😃😃😃 William Orange County California
Sacramento County, hey!
Another case of “learned something I did not know today” Thanks Adam!
I have heard this for years but both my tpi and metric sets are hex and were sold as thread cutting. And I have cut many a thread with them. 45 years ago when purchased I hadn't heard the difference so just went on using them(hex) for both. Still do. Not disagreeing but saying what has worked for years for me.
i bought a tap and die set sold as cutting, it couldnt cut a noodle, ! they do cut, you dont have the advantage of the long arm wrench to help keep it level
Jusb1066 mine came with a hex die wrench and keeping level was no problem. In later years I have used some round dies and haven't seen any better results. The hex I have were from Sears back in the day when their tools were considered good. Today I would buy round but my hex have worked fine.
ahh ive not seen a hex die wrench, my hex dies are HSS and thus inside are the same as a regular die, but i dont have the hex wrench to help get and maintain its level, but i have used it to cut a virgin thread, as i dont have anything else and i rarely need to cut new threads, (well apart from a super cheap set made of carbon steel, they arent split dies but round, and cant cut toffee anyway, but got a single job done back in the day)
I was under impression that the actual shape doesn't matter - the hex is just geared towards people that need to use a wrench to cut the thread - such as tradesmen. I.e. the Hex and Round if both made to cut thread are... thread cutting dies.
Now there is something called re-threading die - which happen to be hex - that is used for "re-threading" only. The way it works is it doesn't cut a thread but moves the metal around - thus it doesn't actually remove much metal.
If you re-thread with thread cutting die you remove extra metal and weaken the thread.
Now 99% of people re-thread with a thread cutting die as they don't care that much about thread strength - but when it is critical you need to use re-threading die ... the also make re-threading taps.
Tom Kitta .. some hex dies are tapered “ like a tap” most are square “ like a bottom tap” and not made for cutting threads
@@daviddale4206 - Thread cutting dies can be ANY SHAPE. Thread chasing / reforming dies can be ANY SHAPE. Most chasing NUTS are hex, so they can be used with a normal spanner.
I did not know that about the hex dies. Thanks for the heads up. Great video