thanks Tom these videos are awesome I have been reading about lathes and machining and watching videos for a couple of years now . My first machine (Lathe is arriving tomorrow ) I am super excited I retired from 32 years in Law enforcement now I am starting a gunsmithing business Cant wait to set up my new lathe and get get started Thanks for all the great info
A classic, "old school" tool grind, and a solid performer. Just the way I was taught many years ago. Don Herbert, TV's original "Mr.Wizard", was a fine teacher who always showed respect for his students, and inspired many of my generation. An apt reference for your many informative videos.
This is my favourite video so far. Only noticed yesterday that I wasn't even subscribed to you the past 4month of watching your videos but I've now subscribed so alls safe thank you for the helping tips.
I used to cook my fingers every time I used a bench grinder to shape HSS. I was watching this vid and feeling the burn. I've adopted a new strategy and it seems to work for me. I use a belt grinder with a pretty coarse ceramic belt on it to rough shape the blank. When it's close, I use a bench grinder that I put diamond wheels on, and that finishes fast and super smooth. For the heavier bits, like Tom's 1/2 inch sample, this works really well. I typically use smaller blanks, 3/8th being the largest normally, and typically, 1/4 inch. Tom you should also mention that surface finish is highly dependent on the quality of the cutting edge on the tool. This can be demonstrated easily. Even a sharp, well formed tool will give lackluster finish if it's rough. You can still screw up the finish a thousand ways, but the only way to get a great finish is to do everything right, tool speed, light depth of cut, surgical polished edge of correct geometry, presented to the workpiece rigidly, saturated with the correct lubricant/coolant. Only then can optimum finish be achieved. Also there are some materials that simply do not finish well. A36 hot rolled steel under the best conditions feels like "cat tongue" when turned because the material tears ahead of the cutting tool ( or so I've heard ). Using some exotic lubricants ( Crisco ) help, but I always leave time for using the toolpost grinder on the stuff if I have to use it. Then there's 12L14/2011/303 which have a very wide envelope of cutting conditions and still give excellent finish. 304 stainless makes stringy chips under just about every condition. Designing geometry, and finding a speed/feed to get chip control on 304 would be nice.
Hi Tom, I use the Red Label Abrasive ceramic belts for the 2x72 grinder in the 36 through the 60 grit versions. I buy them on Amazon usually. The normal belts tend to shred when applying the tool with the sharp part facing the belt travel, the ceramics seem to be OK with it. If I'm really motivated, I'll put the 1000 grit belt on, flip the bit over and get some honing done. My fine diamond wheel is 600 grit I think. I don't have a leather stropping belt for the grinder, but I'd like to try that on my tools eventually.
Thanks Tom (and Adam for that matter), I'm just dipping my toe into machining as a hobby, seems like it's time for me to put some effort into tool grinding. Great video series (and thanks for accommodating the metric folks as well)
Great video as always. This caught my eye in the comments: This is Major Tom to Ground Control I'm starting up the lathe stepping through the door. And I'm floating in a most peculiar way and the chips look very different today. Tom you put big a smile on face..........This ground control to Major Tom, you've really made the grade, and the viewers want know how deep you go, now its time to change your feed rate if you dare...........man you cracked me up! Regards Ralph
Great and timely video Tom. I just went through feeds and speeds with my students, again. Thier goal is to see who can get the longest chip but I've been trying to explain to them that a short chip is best. I'll show them this video and maybe it'll help get my point across. I'm sure it will. Thanks again.
You touched on something that very few mention: changing tool height. So many are so hung on the tool always being exactly on center. I have a lightweight 12x36 Atlas/Craftsman lathe. Probably your carriage weighs as much as my lathe ;). If you raise the center height it does change the rake and front clearance angles and the side becomes a bit of a shear. It also changes the direction of the force on the tool. Rather than straight down it is at an angle. This can change how the toolpost and carriage flex. I have used it to control chatter on a light lathe. Some material just wants to fight you and a smooth finish. Another tool in the arsenal other than feed rate, RPM. and tool angles. I should mention, running a tool above center may help, but you will need to adjust it for every radius. It is a pain to do but can work. Thanks for going outside the box ;) I'm enjoying these chip control videos. Always nice to see what you can do. I'm happy with 0.040 DOC, 0.008 feed and blue chips coming off my small lathe. ;)
Hi Scott, Thanks for the detailed comment. You are correct that its just another tool in your tool box to get the job done or deal with a problem. Cheers, Tom
Tom I really liked your selection of the tool steel grind. I knowingly smiled when you were showing how you planned to grind the tool as I have used these before and grind-ed them myself . All of the angles from the lead angle on to the others make for a very strong efficient tool. I have used carbide inserted tools for roughing which has the same type of angled lead and they really do the work. I enjoyed your processes and results. The Old School way is always good for me. I like the sound of those smaller blue chips clinking around they are just right.
I am definitely going to do a follow up video at some point on my heavy turning video. I was at .030 feed rate with my 1" bit I would have liked to have seen how your 1/2"did at at least .015. I think it might have broken the chip even better. I am thinking crowding the feed rates might result in more faster metal removal than just making a deeper cut. I can't wait to get time and materials to try it with! Thanks for the great insightful video.
Hey Brian, An impressive cut no doubt. I'd for one like to see it closer up and a couple seconds longer. Do you have any 1/2 inch toolbits? Cheers, Tom
I looked in my stash and all I have in 1/2" stuff is some brazed carbide. I don't currently have any material to cut on anyways. I want to do some chip breaker work on my cutter anyways to try to get a turning setup that is clean and doesn't ribbon or throw 1lb chips at me. LOL Busy farming here now, so shop time is limited, but I will get back to it soon. thanks for your interest. Brian
Hi Tom, still trying to get caught up, just a couple weeks behind now, I really like the way you explain as you go and walk us through step by step, I am certainly learning a lot about this whole process. OK, I'll head over to see what Adam is up to next. Boy, with chips like these, my "collection' would really be impressive..... Thanks for a great video ...... Mike
Hi Tom, That's impressive, how many horses to drive the space ship? As we know Adam, as soon as he is finished with the dilemma of the 1/10 of inches, his pride will make him very creative so he doesn't get beaten. As far as HSS hardness is concern, it can be heated up A LOT before it looses it's properties. One test I performed: I welded a piece of HSS to a mandrel, then I tested the hardness on a Rockwell meter, it resulted the same thing on the heated zone as the other end not affected by heat, around 61 to 62 Rockwell C... Impressive material! The little lathes are shivering while we assist to the epic battle, I enjoy this more than TV, Pierre
Nice response Tom. That little bench grinder seems like it has plenty of power for grinding tool bits. What brand is it...just curious. I see you decided to try some back rake on your grind. I wanted to try that on my next round. I think we got some similar results with the cut, but my ultimate goal is to maintain a breaking chip. Thats how I like that cold rolled to form....perfect little curly cues coming off the tool. After I show some deep heavy cutting, I want to get back into my standard chip breakers and how they work for me under normal cutting jobs. I guess I need to fire that coolant pump back up too. I'll just put a drip pan under it when I use it. Lots less smoke then with all the cutting oil...LOL So don't count me out just yet. I got plenty more to show ya! Best regards buddy, Adam
Hey Adam, I switched to the soluble after smoking out the whole shop with cutting oil. Can't wait to see the Abom special chip breakers. Looking forward to the next installment of chip control from Cape Canaveral Florida. Talk to you soon, Tom
If the chip is changing color, you know its doing its job. That is, carrying heat away; from the tool and from the work piece. Well done! On a side note, we have a lathe guy in our shop that absolutely LOVES to let everyone know when he's cutting 304 stainless. The high pitched screeching is an abomination and everyone in the shop despises it and we're not wearing hearing protection and have to listen to it all day sometimes. There are many factors involved when cutting 304. The tool height, the radial depth, the cut per rev, tool condition etc., and yet.... he professes to be an expert but can not rough 304 with no screeching. There IS A WAY gosh dang it!!! and ... what it is I do not know but I would supremely like to show him how to do his job. I've worked a tiny bit on the lathe and am mostly a mill guy but when I cut, I cut. I don't rub and chatter. Any suggestions, Tom or posters here? It is aggravating and bothers everyone in the shop. Is there a way to deal with this with numbers?
Thanks for all the time you take to make vids. In Alaska I dont have alot of machining opportunitys I have worked for 3 shops that closed down wile was there people don't pay or turn wrenches any more so thanks to your amazing teaching ability I still get to learn. So I just bought a 13x40 doall probably over payed now just looking for vfd to for 220 in 3 phaze out and run 5hp. from what i read I need a vfd that is double or triple hp of my lathe because single phase. Or im miss reading and vfds that are 3phase in dont run full power on single phase just confusing to a outdoorsman I can show I how not to get ate by a grizzly or how to gut a moose and fight off bears as you walk in the dark with 100+lbs of blood dripin meat. I can do that but electrical engineer I'm not at least not yet. from ALASKA THANKS FOR ALL THE KNOWLEDGE CANT WAIT FOR YOUR NEXT VID "TEACH" P.s to any 1 who hikes in the woods YOU ARE BEAR BAIT!! In Alaska we know this and we call your orange tents" TWINKES "for bears get it ''YOUR THE CREAM FILLING " hahah
Tom, I HAD to chuckle,@5.07 you mentioned no need for the web etc to use the handy reference book. "It works when the lights are out"....but unfortunately the mill and lathe do not!! LOL Eric
Any micro(say .0001) deviation from a true plane on the leading edge of any cutting tool is actually worse for the drill wearing than just taking the whole edge down to being smooth. In case any of you were wondering why he lapped the tools, he did it because a tool wears from one of 2 things. Either by friction (I.E. gradual dulling in a relatively uniform manner) or by exploiting the inherent geometrical weakness in the chipped portion of metal which causes any chip to still have microfractures around it which only serve to actually keep chipping further instead of wearing. Honing a tool is like shoveling your walkway 2 feet wider if you live in a place with alot of snow. It helps mitigate the amount of times the material need to be removed to still provide reasonable performance. You do not have to hone...They both work, but in a relatively short time the non-honed tool will dramatically decrease in performance. And on a micro scale it will also leave tiny ridges everwhere there was a chip. Wonder what if anything you could do after honing. I assume a chemical coating would further refine the edge as well as possibly eliminating surface pores. And he is absolutely correct, tools do not always cut best at center. But it always has to be close
Tom, Your detail showing on the tool profile geometry grinding is AWESOME!!!!!, Nowhere is there any real clear data on it apparently it just gets absorbed by osmosis just being around old salty machinists!, thanks again for helping the noobs out here floundering along
Hi Boat, Oh cont-rare. There are many books and technical references on single point cutting tools. Remember this is a old technology so there is a lot of written information on it. Check out tool design and cutting tool engineering for more than you ever wanted to know about single point cutting tools. The good old How to run a lathe by Southbend also has some good abbreviated info. Thanks for the comment. Cheers, Tom
Great video Tom. In these days of inserts many people don't realize that HSS is quite capable albeit at a slower volume/time. Being as how this is only a teaser we'll allow you to keep the chipbreaker grind for the real competition... :-) Colin
Hey Colin, Thanks for the comment. I have ground more high speed tools making video's this last year than I have in the previous ten years. Its kinda nice to see how well this stuff actually works again. Cheers, Tom
Let me be clear… I am now much more versed on the relationship between feed, RPM, depth of cut, geometry and sharpening technique. I am just a bit confused as to the specific goals. Thanks!!
Hi Jeff, The goal is in the title. We plan on showing just what is possible with hand ground high speed tools then move into some of the more subtle parts of single point tool geometry. Its a lot easier to get people engaged when you start out with some impressive cuts. Yes its entertainment but lots of things to learn as well if you pay attention and try things yourself. To answer your question straight up, there isn't really an end goal other than to show you guys more about tool grinding and have some fun. All the best, Tom
+Chris Call Hi Chris, Its just a Norton two grit bench stone. The red side is around 220 grit. I rarely use the coarse side. Thanks for the comment. Cheers, Tom
as far i can remember were been things like "chip brakers" or something like this or tool geometry what helps to control chips, without a pictures i cant explain this but i remember how it worked
The HSS cutting speeds in the books and on the charts are based on a 60 minute tool life. GREAT CUTTING TOOL ! Nice cutting with .4375" depth & .010" feed, no more steel wool ! Great to see you using real man's coolant ! By the way those unrealistic high speeds manufacturers recommend for their carbide inserts are based on a 15 minute edge life !
Great video. I love seeing you guys go back and forth and share ideas. Would be great if Keith Fenner would weigh in too. Two questions, what manfacturer/material/grit are your grinding wheels and what is the water based coolant you use? Keep it tasty!
+dragonrc0 Hi Dragon, Kieth did finally weigh in. I can't remember what video it was in but he put some chips down. The wheels are from McMaster Carr. Aluminum oxide 36 grit and 60 grit. I think they were Norton brand. Thanks for the comment. Check out my video on Toms two cents worth on oils and coolants. Cheers, Tom
wow awesome chips Tom. i have a largish (13" swing over bed and 4' between centres) and i think it would struggle with cuts like those, epic work and good tool grind. keep up the good work. off to see what adam comes to the table with. also liking the soluble oil for smoke free cutting. best regards lee
I'd love to see the insides of an aloris type tool post some day, if you're ever opening yours up for any reason...Haven't figured out how how they might have made the dovetail expand like that using a handle motion like that.
Hi Tom, Thanks for the Old School lesson in Basic HSS Turning Tool Grinding. You ground your Top, Side, and End Angles to 10 deg. I wonder if you ground the Top Angle to 5 deg and ground a 1/64th nose radius on the tool, would it help with chip control and surface finish?
Hi, Very interesting watching you grind your tool. Purely for my own interest, can you find time in any video to demonstrate a chip-breaker on one of your home ground tools please? This I have to say is for my interests only as I do not have the capability to grind anymore.
+mrbluenun Hi Blue, I'm pretty sure we get to chipbreakers in some of the face off videos with Adam. In fact I thought there was one in this video. Thanks for the comment. Cheers, Tom
When I first learned to calculate feeds/rpm/chipload I did it longhand. Damn. Wish I had known that immense cheat going in to it. Would have saved at least 2 full pencils and countless pieces of paper.
As much as I realize how much carbide insert tooling has made life in the shop easier I also believe that if you don't know how to grind and use HSS you aren't a machinist. You're an "operator". Well OK maybe a little more than that. I'll use carbide for most operations but for a lot of stuff I switch to HSS for grooving*, threading and form tools. Plus most manual lathes simply cannot take advantage of carbide threading inserts in terms of speed. *A lot of the grooving I do is face grooving for O-rings. The tools for this usually require more than normal side clearance to clear the outer diameter of the groove
Hi M, I agree that you need to know why and how a tool cuts whether its high speed or an insert. If you don't understand how it works its pretty tough to diagnose when you have problems. Thanks for the comment. Cheers, Tom
as i remember as shrper the very tip more easily it brakes so you go to "daimnd" wheal and round sharp corner and polish surfaces (to let chip go easy)
Hi tom, could you at some point make a video about machining tapered parts? Tappered externally and also doing a tapered bore? I can find some videos on it but I would appreciate your take on the topic. James
Hi James, As in things like Jacobs tapers or long tapers like propeller shafts? This is actually a entire class of work for long tapers. Short ones are fairly straight forward. (no pun intended) with the compound, The trick is measuring them. Cheers, Tom
Hi Tom, Nice vid, can i ask what grit/type of course wheel you are using on your grinder? It looked to move the HSS very well, far better than the 36g white AlOx that i use does. Cheers, Ueee
Hi Ueee, Its a Norton AlOx bench grinder wheel from McMaster carr. Nothing fancy at all. It is a hard bond. The white wheels are a much softer bond and break down faster. Is that the problem you are having? Cheers, Tom
oxtoolco Thanks Tom, Yes my wheel does seem to break down fast, leading to rubbing and excessive heat build up. I also use WKE45 (11% Co) almost exclusively which i'm sure does not help! I'm sure i still have the original hard bond wheels that would have come with my grinder, i'll fish one out and see how it cuts. Cheers, Ueee
With the 10° lead angle ground in and the deeper depths of cut you were taking, the cut begins closer to the tool post than to the point, so don't you end up with a matching beveled angle on the shoulder where you stop your cut, almost like it was a form tool?
+Guillaume Fortin Moquin Hi Guillaume, The rotating dressers cover more area on the wheel and don't leave grooves like single point diamonds. Thanks for the comment. Cheers, Tom
Awsome vid Tom. I have a old Craftsman 6" lathe I restored. I have an A2Z QCTP that came with some 3/8 indexable tools, but the lathe cuts much better with 1/4 HSS. The OEM lantern toolpost uses 3/16 tools. Do you have any sugestions for grinding chip brekers on 1/4 HSS or smaller 3/16 HSS.? I bought a craftsman 8" grinder, but such a small chip breker doesn't seem doable on a grinder. Maybe when you get down to a 1/4 HSS chip brakers are thrown out the window. Whats your experience? All the vids and info on tool grinding seem to deal with larger tools 3/8 and up. Thanks in advance, for any help. Ron
Hey Ron, Try a Dremel tool with some of the small Aluminum oxide grinding wheels.The cutting discs don't work that great on high speed steel but the small stones work well. Cheers, Tom
deos getting the bit that hot when grinding it remove its hardness somewhat? im much more cautious when i grind a drill bit for example, which is also hss
Hi Jusb, High speed steel retains its hardness and strength at red heat. Even through there is some color from the grinding this does not impair the cutting edge. Cheers, Tom
Tom and Adam… I think I might be a little unclear as to the specific goals. Bear in mind that I am watching other youTube videos of others who are following your lead. It seems that the overall goal is how big of a chip can you take. I really am not trying to be a smart ass… But as a "newcomer" to machinery and your skill set, I am soaking up the information and this seems important to me. So, please, what are your specific goals for this series? Thanks for what you are doing!!
Hi Tom, old school worked well! That's how it hung in there long enough to be old! I'm getting pretty old, and it's mostly my way... ;o] For the most part that was just how I'd grind it. Perhaps depending on material, and machine/machinist (chips)... I may have put just a "tiny" bit more radius on the point,,, (very slight). There was not even the least little bit of strain coming from the sound of your lathe... It seems to be quite a nice machine! Y'all are creating quite a nice series and are great teachers. Thank you... :o] O
Hey O, Normally I use a slightly larger radius as well. Watching Adam on the first chip control I decided to try a real minimal radius on the first tool and it seemed to hold up fine. The lathe can take the strain but the tool clamping will become an issue pretty quick. Thanks for the comment. Best, Tom
Hi Tom, a question on the ´finger-rest you have installed at the grinder disc. What is the tilt(approx.)? Do you have it setup at 0 degrees tilt(meaning flat) or do you have a slight angle? I mean the L-shaped metalplate surrounding your grinding disc?
Where are the chips? I just see dangerous hand-shredding curlies? There was a tiny bit of chip control as you raised the elevation slightly but it still looks like curlies will give big issues in an automated cut situation here.
Why do you have to deepen the top back rate. Would it give the same result if you give that 10 degrees but let the tool ½" solid? You remove nearly a ¼ " from the top but you a add a ¼" shim. It's as in the Atlas book "How to run a lathe" but in those times they used lantern tool post. You use an Aloris straight tool post. Most interesting video. Speed rate and RPM is not an easy thing to understand. Hope that you will talk more about that subject. Mainly Speed rate & RPM for standard cut, for us who live on the earth and finishing cut the old way, for those who are older than you 😉 thanks again. Merci
Hi Robert, The shim is only to provide a no slip surface between the tool and the tool holder. Aggressive cutting can rotate the tool in the tool holder. It was not to make up for lost height. The back rack makes the top edge more positive and free cutting. Cheers, Tom
Tom, that is pretty impressive now if you could convert it to making curly fries I would declare you the winner..my poor little old lathe would be weeping if I showed it this video.
Hey Randy, I think all the Grizzly's and Sherline's are shivering in the corner right about now worried their owners are coming out to the garage to have some fun. Cheers, Tom
oxtoolco So far my limit on a 1.5 hp lathe with mild steel is about .100 total dia removed (using carbide). There may be a little more left, but I haven't progressed that far. But yes, my lathe shivers when I show it videos from you guys. :)
Hey Tom... I am confused...7/8" depth of cut is really TIR, the actual ("in feed") contact of the cut is 7/16" Confused or correct or are we talking the same? Chuck
Were was this video 2 years ago when I was making a lot of smoke and black chips! I assume you are going to delve into grinding a chipbreaker in a later video. What is your preferred coolant? This was a great video, hss can be extremely frustrating.
Hi Tyler, Black chips are only good for dipping in salsa. Not sure where this series will lead. I'm pretty sure we will get into chipbreakers at some point. Cheers, Tom
While the two videos so far have been very interesting and helpful, I must confess that my interest in "How Much and How Fast" is quite limited. I'm actually much more interested in how to adapt the grinds and other variables to provide the best finish on a variety of materials. For example, if you used the same bit/grind and substituted aluminum or stainless steel or brass or cast iron or 4140 for the 1018, how would the finish be? How can the grind be adjusted to minimize build-up on the edge? How can the grind be modified to allow the bit to work longer (with a good finish) between sharpenings? If the goal is the ultimate finish right off the tool (no subsequent polishing) what's the best way to grind and use the tool for different materials? Thanks. -Chris
Hey Chris, The short story is it depends. This tool will work on all the materials you mention. Better on some and worse on others. There is an interconnected relationship between the tool geometry material and feedrate that we modify to produce different characteristics. If surface finish is the only goal it is a very different set of parameters and tool geometry. As you can see in carbide inserts as an example there are a huge number of available tools just for straight turning each with its own particular focus and strengths. Its not far wrong that the story is the same for hand ground high speed steel tools. The purpose of this series is to show what can be done first of all, and what some of the knobs we as machinist have available to make changes. From there its optimization for your specific requirements. No tool does everything is an accurate statement. I can't give you a general answer that works unless you get very specific. Hope this helps. All the best, Tom
Hi, Tom. thanks for the schooling on tool bits. i think i was making mine wrong all this time, my nose radius are huge and side loading my work pieces. your equation: what is the units or value of the "4" or is it a consistent??? thanks for the great videos. sorry about the stupid questions.
Hi Sam, Four is an approximation of the conversion of feet per minute to revolutions per minute. Its an easier number to work with than 3.82 when doing work at the machine. Cheers, Tom
Hey Major Tom, (any relation to David Bowie?) Thanks for the Chips Ahoy video. It is interesting how all the variables (cutter profile, spindle speed, feed rate, etc.) have such a profound effect of chip shape and color. Those last ones were getting pretty toasty! I'd love to join in, but the 13" Birmingham I am ordering (2hp motor) wouldn't cut the mustard, let alone a .800+ chip! Thanks for the info. BTW, what grit grinding wheels do you use? The first one appeared rather hungry. Regards, Oxen Dave
Hey Dave, This is Major Tom to Ground Control I'm starting up the lathe stepping through the door. And I'm floating in a most peculiar way And the chips look very different today Cheers Tom
oxtoolco Hey Tom . . . That was great! I laughed my ass off! (Now I have a major problem going to the bathroom!) The chips are never down between you and Adam (LOL) Oxen Dave
Great video as usual. Important question, arduinovsevil is needing a sidekick for his fight against evil. Would you possibly consider wearing spandex tights with your underwear on the outside? I hope you don't wear some embarrassing underwear like Hello Kitty or anything.
I was thinking short high degree tapers like you might use to machine a model rocket nozzle. But long propeller shaft tapering whould also be interesting
Want a tough test for your chip breaker, try some 17-4. I was turning some 17-4 a few days ago, and generally being lazy grabbed my toolholder that already had a nice cutter in it set on-center, however sans chip breaker. It shot out a long lethal ribbon that you wouldn't believe! Made me rethink what I was doing because I wanted to live!
Greetings- I was trying to point out to others who have light duty 3 jaw chucks and a short purchase that they would have trouble making this depth of cut without using a tail stock. I have had it happen to me many times with a 12 inch atlas and short purchase. More likely, the part will move into the chuck as far as it can, and the part will slip in the chuck. I suspect your surface finish would be better with a tailstock. Jim
I have to ask, you have a perfectly capable surface grinder why did you not use that to flatten your cutting surfaces? do you want curved cutting edges? A rounded nose ensures a single point of contact to the work, so a larger nose gives you a lot more play with you tool centerline I saw you made your radius bigger but why did you stop there? (most inserts have a much larger nose radius) Why did you not cut a chip break behind the top cutting surface and rather load the tool until you had the chips break after hardening? I'm under the impression that hot chips equal tool wear, so a chip that breaks cool is a much better chip. I'm a novice that hasn't touched a lathe in 20+ years but I want to pick it up again (retirement has its advantages) Just curious if my understanding is in line with your experience.
Hi Sy, Setting up the surface grinder and making the edges perfectly flat does not increase cutting efficiency enough to expend the time to set up the angles and machine grind them. Offhand grinding was the subject of the video and well within the capabilities of most folks with a normal bench grinder. Thanks for the comment. Cheers, Tom
Some people worry at the raise of bit temperature during heavy grinding. Mr. James A. Harvey, author of "Machine Shop Trade Secrets" conducted extensive tests on the subject checking hardness of bits before and after getting blue by abusive grinding of cobalt bits and found no difference in properties or performance. By the way Tom, I always wonder at the lack of a cooling system in your nice lathe. I personally prefer full synthetic oil to cover both cooling and lubricating needs and avoid fungus, odor and other unpleasant features of soluble cutting oil. Regards Jorge
Hi Jorge, Thanks for the information. You are correct that high speed steel with or without cobalt retains its hardness and functional properties even at red heat. When buried in a cut the fine edge see's a very high temperature indeed. On the oil and coolant I prefer low volume methods. Slinging coolant around by the gallon is for production machines. Most hobby and prototype shops can get by with very minimal amounts of coolant and oil for most machining. Cheers, Tom
oxtoolco Very true. Also mist cooling is detrimental and counterproductive with Widia/Carbide inserts who due to thermal shock work best with flood. Many people by using a chuck guard use flood to extend tool life and help in chip sticking and removal during heavy cutting. Same in the mill with some sort of guard or cover to contain coolant splash. Fenner uses it when needed but of course he does production and as you properly stated the task and conditions are different, Cheers
Hi Deric, Its a six jaw chuck. The jaws are not independent. They move on a scroll much like a three jaw self centering. Thanks for the comment. Cheers, Tom
Hi Jack, Aluminum oxide one side coarse say 36-46 grit and one finer on the opposite side 60-80 grit. These are plain bench grinder wheels from McMaster Carr. Cheers, Tom
Hi Ray, I have two grits on my bench grinder. Something like a 60 grit and an 80 grit aluminum oxide. Got them from McMaster. Thanks for the comment. Cheers, Tom
I cant help wondering if you have ever heard of 'Heat treatment' bcoz you get your HSS so hot when grinding it goes blue. I would go so far as to suggest that is completely the wrong wheel for grinding that metal, but, Meh, what would I know?
thanks Tom these videos are awesome I have been reading about lathes and machining and watching videos for a couple of years now . My first machine (Lathe is arriving tomorrow ) I am super excited I retired from 32 years in Law enforcement now I am starting a gunsmithing business Cant wait to set up my new lathe and get get started Thanks for all the great info
The title of this video amuses me far more than it should, I'm sure it's been commented on before but A++
A classic, "old school" tool grind, and a solid performer. Just the way I was taught many years ago. Don Herbert, TV's original "Mr.Wizard", was a fine teacher who always showed respect for his students, and inspired many of my generation. An apt reference for your many informative videos.
Hi Shobar,
Thanks for the comment. Mr Wizard approves of this post.
Cheers,
Tom
This is my favourite video so far. Only noticed yesterday that I wasn't even subscribed to you the past 4month of watching your videos but I've now subscribed so alls safe thank you for the helping tips.
Onur Caglar Hi Onur,
Thanks for the sub and comment.
Cheers,
Tom
I used to cook my fingers every time I used a bench grinder to shape HSS. I was watching this vid and feeling the burn. I've adopted a new strategy and it seems to work for me. I use a belt grinder with a pretty coarse ceramic belt on it to rough shape the blank. When it's close, I use a bench grinder that I put diamond wheels on, and that finishes fast and super smooth. For the heavier bits, like Tom's 1/2 inch sample, this works really well. I typically use smaller blanks, 3/8th being the largest normally, and typically, 1/4 inch.
Tom you should also mention that surface finish is highly dependent on the quality of the cutting edge on the tool. This can be demonstrated easily. Even a sharp, well formed tool will give lackluster finish if it's rough. You can still screw up the finish a thousand ways, but the only way to get a great finish is to do everything right, tool speed, light depth of cut, surgical polished edge of correct geometry, presented to the workpiece rigidly, saturated with the correct lubricant/coolant. Only then can optimum finish be achieved. Also there are some materials that simply do not finish well. A36 hot rolled steel under the best conditions feels like "cat tongue" when turned because the material tears ahead of the cutting tool ( or so I've heard ). Using some exotic lubricants ( Crisco ) help, but I always leave time for using the toolpost grinder on the stuff if I have to use it. Then there's 12L14/2011/303 which have a very wide envelope of cutting conditions and still give excellent finish. 304 stainless makes stringy chips under just about every condition. Designing geometry, and finding a speed/feed to get chip control on 304 would be nice.
Hi Jeff,
What belt do you like for grinding high speed steel? Thanks for the comment.
Cheers,
Tom
Hi Tom, I use the Red Label Abrasive ceramic belts for the 2x72 grinder in the 36 through the 60 grit versions. I buy them on Amazon usually. The normal belts tend to shred when applying the tool with the sharp part facing the belt travel, the ceramics seem to be OK with it. If I'm really motivated, I'll put the 1000 grit belt on, flip the bit over and get some honing done. My fine diamond wheel is 600 grit I think. I don't have a leather stropping belt for the grinder, but I'd like to try that on my tools eventually.
Great first Round. The ole school grind is pretty awesome! Thanks for sharing.
Hey Herb,
Old school rules!
Cheers,
Tom
Thanks Tom (and Adam for that matter), I'm just dipping my toe into machining as a hobby, seems like it's time for me to put some effort into tool grinding. Great video series (and thanks for accommodating the metric folks as well)
Man, you are the man! I went through a very vigorous apprenticeship and years of jobs, and I never did that, lap the tool, I will be doing that now!
+Stephen Hodge Hey Stephen,
Dress for success. Honing is the secret sauce on a tool bit. Thanks for the comment.
Cheers,
Tom
Thanks for taking the time to experiment with different cuts and tool positions.
Great video as always.
This caught my eye in the comments: This is Major Tom to Ground Control I'm starting up the lathe stepping through the door. And I'm floating in a most peculiar way and the chips look very different today.
Tom you put big a smile on face..........This ground control to Major Tom, you've really made the grade, and the viewers want know how deep you go, now its time to change your feed rate if you dare...........man you cracked me up!
Regards
Ralph
Hey Ralph,
Glad you liked my little joke. I'll probably get sued by David Bowie but it was worth it.
Cheers,
Tom
Great and timely video Tom. I just went through feeds and speeds with my students, again. Thier goal is to see who can get the longest chip but I've been trying to explain to them that a short chip is best. I'll show them this video and maybe it'll help get my point across. I'm sure it will. Thanks again.
Hey Duane,
You will never convince a kid that a short chip is cool. Its the way of the world.
All the best.
Tom
oxtoolco But you can easily show them that short chip is hot... hot is good up to a point... right? :)
Remember grinding high speed tooling when I started in a machine shop . Turning tool threading tool and necking tool and drill bits .
Wow I was surprised to see high speed steel take such a large bite. Definitely need to try some of these grinds.
M&R JOHNSON
Hi Ryan,
Thanks for the comment. If you don't know where the envelope is its hard to tell when your pushing it.
All the best,
Tom
All those chips and no dip. Nice grind Tom it worked great.
You touched on something that very few mention: changing tool height. So many are so hung on the tool always being exactly on center.
I have a lightweight 12x36 Atlas/Craftsman lathe. Probably your carriage weighs as much as my lathe ;).
If you raise the center height it does change the rake and front clearance angles and the side becomes a bit of a shear. It also changes the direction of the force on the tool. Rather than straight down it is at an angle. This can change how the toolpost and carriage flex.
I have used it to control chatter on a light lathe. Some material just wants to fight you and a smooth finish. Another tool in the arsenal other than feed rate, RPM. and tool angles.
I should mention, running a tool above center may help, but you will need to adjust it for every radius. It is a pain to do but can work.
Thanks for going outside the box ;) I'm enjoying these chip control videos. Always nice to see what you can do. I'm happy with 0.040 DOC, 0.008 feed and blue chips coming off my small lathe. ;)
Hi Scott,
Thanks for the detailed comment. You are correct that its just another tool in your tool box to get the job done or deal with a problem.
Cheers,
Tom
Tom I really liked your selection of the tool steel grind. I knowingly smiled when you were showing how you planned to grind the tool as I have used these before and grind-ed them myself . All of the angles from the lead angle on to the others make for a very strong efficient tool. I have used carbide inserted tools for roughing which has the same type of angled lead and they really do the work. I enjoyed your processes and results. The Old School way is always good for me. I like the sound of those smaller blue chips clinking around they are just right.
Hey Lou,
Thanks for the comment. Old school rules.
Cheers,
Tom
I am definitely going to do a follow up video at some point on my heavy turning video. I was at .030 feed rate with my 1" bit I would have liked to have seen how your 1/2"did at at least .015. I think it might have broken the chip even better. I am thinking crowding the feed rates might result in more faster metal removal than just making a deeper cut. I can't wait to get time and materials to try it with! Thanks for the great insightful video.
Hey Brian,
An impressive cut no doubt. I'd for one like to see it closer up and a couple seconds longer. Do you have any 1/2 inch toolbits?
Cheers,
Tom
I looked in my stash and all I have in 1/2" stuff is some brazed carbide. I don't currently have any material to cut on anyways. I want to do some chip breaker work on my cutter anyways to try to get a turning setup that is clean and doesn't ribbon or throw 1lb chips at me. LOL Busy farming here now, so shop time is limited, but I will get back to it soon. thanks for your interest.
Brian
Had me at the edge of my chair towards the end, was expecting that tool to give in. lol. Nice job Tom.
Hey Steve,
Its still got some more up its sleeve. Thanks for the comment.
Cheers,
Tom
Hi Tom, still trying to get caught up, just a couple weeks behind now, I really like the way you explain as you go and walk us through step by step, I am certainly learning a lot about this whole process. OK, I'll head over to see what Adam is up to next. Boy, with chips like these, my "collection' would really be impressive.....
Thanks for a great video ...... Mike
Hi Mike,
Always nice to hear from you. I see you are keeping the wheels of industry turning. Make hay when the sun is shining right?
All the best,
Tom
Hi Tom, Nice job and I am learning lots from this. I liked Abom's grind also. Thanks M.K.S.
Hi Tom,
That's impressive, how many horses to drive the space ship?
As we know Adam, as soon as he is finished with the dilemma of the 1/10 of inches, his pride will make him very creative so he doesn't get beaten.
As far as HSS hardness is concern, it can be heated up A LOT before it looses it's properties. One test I performed: I welded a piece of HSS to a mandrel, then I tested the hardness on a Rockwell meter, it resulted the same thing on the heated zone as the other end not affected by heat, around 61 to 62 Rockwell C... Impressive material!
The little lathes are shivering while we assist to the epic battle, I enjoy this more than TV,
Pierre
Hi Pierre,
We left some headroom for Adam for a comeback. I'm sure he will put on a good showing.
Cheers,
Tom
great video...I'm having a flashback to my days of grinding HSS in tech school and not paying attention, slipping and getting good finger grinds!!
Nice response Tom. That little bench grinder seems like it has plenty of power for grinding tool bits. What brand is it...just curious.
I see you decided to try some back rake on your grind. I wanted to try that on my next round.
I think we got some similar results with the cut, but my ultimate goal is to maintain a breaking chip. Thats how I like that cold rolled to form....perfect little curly cues coming off the tool.
After I show some deep heavy cutting, I want to get back into my standard chip breakers and how they work for me under normal cutting jobs.
I guess I need to fire that coolant pump back up too. I'll just put a drip pan under it when I use it. Lots less smoke then with all the cutting oil...LOL
So don't count me out just yet. I got plenty more to show ya!
Best regards buddy,
Adam
Hey Adam,
I switched to the soluble after smoking out the whole shop with cutting oil. Can't wait to see the Abom special chip breakers. Looking forward to the next installment of chip control from Cape Canaveral Florida.
Talk to you soon,
Tom
If the chip is changing color, you know its doing its job. That is, carrying heat away; from the tool and from the work piece. Well done! On a side note, we have a lathe guy in our shop that absolutely LOVES to let everyone know when he's cutting 304 stainless. The high pitched screeching is an abomination and everyone in the shop despises it and we're not wearing hearing protection and have to listen to it all day sometimes. There are many factors involved when cutting 304. The tool height, the radial depth, the cut per rev, tool condition etc., and yet.... he professes to be an expert but can not rough 304 with no screeching. There IS A WAY gosh dang it!!! and ... what it is I do not know but I would supremely like to show him how to do his job. I've worked a tiny bit on the lathe and am mostly a mill guy but when I cut, I cut. I don't rub and chatter.
Any suggestions, Tom or posters here? It is aggravating and bothers everyone in the shop. Is there a way to deal with this with numbers?
Thanks for all the time you take to make vids. In Alaska I dont have alot of machining opportunitys I have worked for 3 shops that closed down wile was there people don't pay or turn wrenches any more so thanks to your amazing teaching ability I still get to learn. So I just bought a 13x40 doall probably over payed now just looking for vfd to for 220 in 3 phaze out and run 5hp. from what i read I need a vfd that is double or triple hp of my lathe because single phase. Or im miss reading and vfds that are 3phase in dont run full power on single phase just confusing to a outdoorsman I can show I how not to get ate by a grizzly or how to gut a moose and fight off bears as you walk in the dark with 100+lbs of blood dripin meat. I can do that but electrical engineer I'm not at least not yet.
from ALASKA THANKS FOR ALL THE KNOWLEDGE CANT WAIT FOR YOUR NEXT VID "TEACH"
P.s to any 1 who hikes in the woods YOU ARE BEAR BAIT!! In Alaska we know this and we call your orange tents" TWINKES "for bears get it ''YOUR THE CREAM FILLING " hahah
Tom, I HAD to chuckle,@5.07 you mentioned no need for the web etc to use the handy reference book. "It works when the lights are out"....but unfortunately the mill and lathe do not!! LOL
Eric
It may work with the lights out, but it's hard to read the info.
Dave
Hey Eric,
Touche! You can look that up with you're smart phone......
Cheers,
Tom
LOL! I don't have one but I "learnt" what it means in 3rd grade:-)
Eric
Any micro(say .0001) deviation from a true plane on the leading edge of any cutting tool is actually worse for the drill wearing than just taking the whole edge down to being smooth. In case any of you were wondering why he lapped the tools, he did it because a tool wears from one of 2 things. Either by friction (I.E. gradual dulling in a relatively uniform manner) or by exploiting the inherent geometrical weakness in the chipped portion of metal which causes any chip to still have microfractures around it which only serve to actually keep chipping further instead of wearing.
Honing a tool is like shoveling your walkway 2 feet wider if you live in a place with alot of snow. It helps mitigate the amount of times the material need to be removed to still provide reasonable performance. You do not have to hone...They both work, but in a relatively short time the non-honed tool will dramatically decrease in performance. And on a micro scale it will also leave tiny ridges everwhere there was a chip.
Wonder what if anything you could do after honing. I assume a chemical coating would further refine the edge as well as possibly eliminating surface pores. And he is absolutely correct, tools do not always cut best at center. But it always has to be close
Tom, Your detail showing on the tool profile geometry grinding is AWESOME!!!!!, Nowhere is there any real clear data on it apparently it just gets absorbed by osmosis just being around old salty machinists!, thanks again for helping the noobs out here floundering along
Hi Boat,
Oh cont-rare. There are many books and technical references on single point cutting tools. Remember this is a old technology so there is a lot of written information on it. Check out tool design and cutting tool engineering for more than you ever wanted to know about single point cutting tools. The good old How to run a lathe by Southbend also has some good abbreviated info. Thanks for the comment.
Cheers,
Tom
@@oxtoolco that is a good book.
I have it.
Great video Tom. In these days of inserts many people don't realize that HSS is quite capable albeit at a slower volume/time. Being as how this is only a teaser we'll allow you to keep the chipbreaker grind for the real competition... :-)
Colin
Hey Colin,
Thanks for the comment. I have ground more high speed tools making video's this last year than I have in the previous ten years. Its kinda nice to see how well this stuff actually works again.
Cheers,
Tom
Love the videos. Thanks heaps for the metric notations.
+Tristan Patterson Hi Tristan,
Newtons to you. Thanks for the comment.
Cheers,
Tom
Let me be clear… I am now much more versed on the relationship between feed, RPM, depth of cut, geometry and sharpening technique. I am just a bit confused as to the specific goals. Thanks!!
Hi Jeff,
The goal is in the title. We plan on showing just what is possible with hand ground high speed tools then move into some of the more subtle parts of single point tool geometry. Its a lot easier to get people engaged when you start out with some impressive cuts. Yes its entertainment but lots of things to learn as well if you pay attention and try things yourself. To answer your question straight up, there isn't really an end goal other than to show you guys more about tool grinding and have some fun.
All the best,
Tom
There is no end. Pay attention😂
Can you tell more about the honing stone?
+Chris Call Hi Chris,
Its just a Norton two grit bench stone. The red side is around 220 grit. I rarely use the coarse side. Thanks for the comment.
Cheers,
Tom
Thanks.
I truly like your desire to show your talents so many times I wanted to leave this trade.
as far i can remember were been things like "chip brakers" or something like this or tool geometry what helps to control chips, without a pictures i cant explain this but i remember how it worked
These videos are going to help me a bunch! Thanks
Thanks Tom that's helped me a lot on tool grinding
The HSS cutting speeds in the books and on the charts are based on a 60 minute tool life. GREAT CUTTING TOOL ! Nice cutting with .4375" depth & .010" feed, no more steel wool !
Great to see you using real man's coolant ! By the way those unrealistic high speeds manufacturers recommend for their carbide inserts are based on a 15 minute edge life !
What grit is the lapping stone? Big thanks to you and Adam taking the time to make these videos.
Hi Nunya,
Approx 320 Grit on the reddish side.
Cheers,
Tom
Great video. I love seeing you guys go back and forth and share ideas. Would be great if Keith Fenner would weigh in too. Two questions, what manfacturer/material/grit are your grinding wheels and what is the water based coolant you use? Keep it tasty!
+dragonrc0 Hi Dragon,
Kieth did finally weigh in. I can't remember what video it was in but he put some chips down. The wheels are from McMaster Carr. Aluminum oxide 36 grit and 60 grit. I think they were Norton brand. Thanks for the comment. Check out my video on Toms two cents worth on oils and coolants.
Cheers,
Tom
WOW! As always, thanks’ for taking the time to make this video! And I support this site. ~M~
Nice one Tom - look forward to see what Adam has up his sleeves.
-hhilm
what a monster of a lathe you have, i'm awe struk
Great title for the video chip control to Major Tom.
wow awesome chips Tom. i have a largish (13" swing over bed and 4' between centres) and i think it would struggle with cuts like those, epic work and good tool grind.
keep up the good work. off to see what adam comes to the table with.
also liking the soluble oil for smoke free cutting.
best regards
lee
That was a demanding cut! That lathe has grunt!
+Pete Macrae Hi Pete,
Thanks for the comment.
Cheers,
Tom
the carbide tip actually dissipates the heat from the cut so you can so in higher speeds with the carbide bits
I'd love to see the insides of an aloris type tool post some day, if you're ever opening yours up for any reason...Haven't figured out how how they might have made the dovetail expand like that using a handle motion like that.
Hi Tom, Thanks for the Old School lesson in Basic HSS Turning Tool Grinding.
You ground your Top, Side, and End Angles to 10 deg.
I wonder if you ground the Top Angle to 5 deg and ground a 1/64th nose radius on the tool,
would it help with chip control and surface finish?
Hi,
Very interesting watching you grind your tool. Purely for my own interest, can you find time in any video to demonstrate a chip-breaker on one of your home ground tools please? This I have to say is for my interests only as I do not have the capability to grind anymore.
+mrbluenun Hi Blue,
I'm pretty sure we get to chipbreakers in some of the face off videos with Adam. In fact I thought there was one in this video. Thanks for the comment.
Cheers,
Tom
When I first learned to calculate feeds/rpm/chipload I did it longhand.
Damn.
Wish I had known that immense cheat going in to it.
Would have saved at least 2 full pencils and countless pieces of paper.
Your grind reminded me of a ship's bow. I like it.
As much as I realize how much carbide insert tooling has made life in the shop easier I also believe that if you don't know how to grind and use HSS you aren't a machinist. You're an "operator". Well OK maybe a little more than that. I'll use carbide for most operations but for a lot of stuff I switch to HSS for grooving*, threading and form tools. Plus most manual lathes simply cannot take advantage of carbide threading inserts in terms of speed.
*A lot of the grooving I do is face grooving for O-rings. The tools for this usually require more than normal side clearance to clear the outer diameter of the groove
Hi M,
I agree that you need to know why and how a tool cuts whether its high speed or an insert. If you don't understand how it works its pretty tough to diagnose when you have problems. Thanks for the comment.
Cheers,
Tom
Im learning a lot Tom! thanks for todays lesson !
Can you make some videos about how to get a smooth finish by grinding nose radius Ox? I think it will be very helpful. Thank you so much!
as i remember as shrper the very tip more easily it brakes so you go to "daimnd" wheal and round sharp corner and polish surfaces (to let chip go easy)
Hi tom, could you at some point make a video about machining tapered parts? Tappered externally and also doing a tapered bore? I can find some videos on it but I would appreciate your take on the topic.
James
Hi James,
As in things like Jacobs tapers or long tapers like propeller shafts? This is actually a entire class of work for long tapers. Short ones are fairly straight forward. (no pun intended) with the compound, The trick is measuring them.
Cheers,
Tom
Hi Tom,
Nice vid, can i ask what grit/type of course wheel you are using on your grinder? It looked to move the HSS very well, far better than the 36g white AlOx that i use does.
Cheers,
Ueee
Hi Ueee,
Its a Norton AlOx bench grinder wheel from McMaster carr. Nothing fancy at all. It is a hard bond. The white wheels are a much softer bond and break down faster. Is that the problem you are having?
Cheers,
Tom
oxtoolco
Thanks Tom,
Yes my wheel does seem to break down fast, leading to rubbing and excessive heat build up. I also use WKE45 (11% Co) almost exclusively which i'm sure does not help! I'm sure i still have the original hard bond wheels that would have come with my grinder, i'll fish one out and see how it cuts.
Cheers,
Ueee
Well done!
Show me your chips, I'll evaluate your craftmanship...
very interesting tom about the feed rates higher feed rate looks a better chip
With the 10° lead angle ground in and the deeper depths of cut you were taking, the cut begins closer to the tool post than to the point, so don't you end up with a matching beveled angle on the shoulder where you stop your cut, almost like it was a form tool?
Very well explained , as usual !
But why don't you use these diamond tipped wheel dresser instead of this ninja star ones??
+Guillaume Fortin Moquin Hi Guillaume,
The rotating dressers cover more area on the wheel and don't leave grooves like single point diamonds. Thanks for the comment.
Cheers,
Tom
Awsome vid Tom.
I have a old Craftsman 6" lathe I restored. I have an A2Z QCTP that came with some 3/8 indexable tools, but the lathe cuts much better with 1/4 HSS. The OEM lantern toolpost uses 3/16 tools. Do you have any sugestions for grinding chip brekers on 1/4 HSS or smaller 3/16 HSS.? I bought a craftsman 8" grinder, but such a small chip breker doesn't seem doable on a grinder. Maybe when you get down to a 1/4 HSS chip brakers are thrown out the window. Whats your experience?
All the vids and info on tool grinding seem to deal with larger tools 3/8 and up.
Thanks in advance, for any help.
Ron
Hey Ron,
Try a Dremel tool with some of the small Aluminum oxide grinding wheels.The cutting discs don't work that great on high speed steel but the small stones work well.
Cheers,
Tom
Outstanding dem and explanation!!
deos getting the bit that hot when grinding it remove its hardness somewhat? im much more cautious when i grind a drill bit for example, which is also hss
Hi Jusb,
High speed steel retains its hardness and strength at red heat. Even through there is some color from the grinding this does not impair the cutting edge.
Cheers,
Tom
oxtoolco
thanks tom for the info
Tom and Adam… I think I might be a little unclear as to the specific goals. Bear in mind that I am watching other youTube videos of others who are following your lead. It seems that the overall goal is how big of a chip can you take. I really am not trying to be a smart ass… But as a "newcomer" to machinery and your skill set, I am soaking up the information and this seems important to me. So, please, what are your specific goals for this series? Thanks for what you are doing!!
Hi Tom, old school worked well! That's how it hung in there long enough to be old! I'm getting pretty old, and it's mostly my way... ;o] For the most part that was just how I'd grind it. Perhaps depending on material, and machine/machinist (chips)... I may have put just a "tiny" bit more radius on the point,,, (very slight). There was not even the least little bit of strain coming from the sound of your lathe... It seems to be quite a nice machine! Y'all are creating quite a nice series and are great teachers. Thank you... :o]
O
Hey O,
Normally I use a slightly larger radius as well. Watching Adam on the first chip control I decided to try a real minimal radius on the first tool and it seemed to hold up fine. The lathe can take the strain but the tool clamping will become an issue pretty quick. Thanks for the comment.
Best,
Tom
Thanks for the video, I could see a lot.
Hi Tom,
a question on the ´finger-rest you have installed at the grinder disc. What is the tilt(approx.)? Do you have it setup at 0 degrees tilt(meaning flat) or do you have a slight angle? I mean the L-shaped metalplate surrounding your grinding disc?
Hi Chippie,
Its flat and on the center of the wheel. Sometimes I tip the edge closest to the wheel up a bit if I want more clearance.
Cheers,
Tom
Where are the chips?
I just see dangerous hand-shredding curlies?
There was a tiny bit of chip control as you raised the elevation slightly but it still looks like curlies will give big issues in an automated cut situation here.
Why do you have to deepen the top back rate. Would it give the same result if you give that 10 degrees but let the tool ½" solid? You remove nearly a ¼ " from the top but you a add a ¼" shim. It's as in the Atlas book "How to run a lathe" but in those times they used lantern tool post. You use an Aloris straight tool post. Most interesting video. Speed rate and RPM is not an easy thing to understand. Hope that you will talk more about that subject. Mainly Speed rate & RPM for standard cut, for us who live on the earth and finishing cut the old way, for those who are older than you 😉
thanks again.
Merci
Hi Robert,
The shim is only to provide a no slip surface between the tool and the tool holder. Aggressive cutting can rotate the tool in the tool holder. It was not to make up for lost height. The back rack makes the top edge more positive and free cutting.
Cheers,
Tom
Tom, that is pretty impressive now if you could convert it to making curly fries I would declare you the winner..my poor little old lathe would be weeping if I showed it this video.
Hey Randy,
I think all the Grizzly's and Sherline's are shivering in the corner right about now worried their owners are coming out to the garage to have some fun.
Cheers,
Tom
oxtoolco So far my limit on a 1.5 hp lathe with mild steel is about .100 total dia removed (using carbide). There may be a little more left, but I haven't progressed that far. But yes, my lathe shivers when I show it videos from you guys. :)
Love what you are doing, subscribed.
Hey Johnny,
Don't blow it all on one channel. Thanks for the comment.
Cheers,
Tom
You make grinding the tool so easy. I guess experience counts. What kind of stone are you grinding with. Thanks for all your videos.
Hey Tom...
I am confused...7/8" depth of cut is really TIR, the actual ("in feed") contact of the cut is 7/16"
Confused or correct or are we talking the same?
Chuck
40:50 I say it correctly. At the end I bozoed the diameter versus radius.
7/8 on the diameter 7/16 radial.
Best,
Tom
Were was this video 2 years ago when I was making a lot of smoke and black chips!
I assume you are going to delve into grinding a chipbreaker in a later video.
What is your preferred coolant?
This was a great video, hss can be extremely frustrating.
Hi Tyler,
Black chips are only good for dipping in salsa. Not sure where this series will lead. I'm pretty sure we will get into chipbreakers at some point.
Cheers,
Tom
While the two videos so far have been very interesting and helpful, I must confess that my interest in "How Much and How Fast" is quite limited. I'm actually much more interested in how to adapt the grinds and other variables to provide the best finish on a variety of materials. For example, if you used the same bit/grind and substituted aluminum or stainless steel or brass or cast iron or 4140 for the 1018, how would the finish be? How can the grind be adjusted to minimize build-up on the edge? How can the grind be modified to allow the bit to work longer (with a good finish) between sharpenings? If the goal is the ultimate finish right off the tool (no subsequent polishing) what's the best way to grind and use the tool for different materials? Thanks.
-Chris
Hey Chris,
The short story is it depends. This tool will work on all the materials you mention. Better on some and worse on others. There is an interconnected relationship between the tool geometry material and feedrate that we modify to produce different characteristics. If surface finish is the only goal it is a very different set of parameters and tool geometry. As you can see in carbide inserts as an example there are a huge number of available tools just for straight turning each with its own particular focus and strengths. Its not far wrong that the story is the same for hand ground high speed steel tools. The purpose of this series is to show what can be done first of all, and what some of the knobs we as machinist have available to make changes. From there its optimization for your specific requirements. No tool does everything is an accurate statement. I can't give you a general answer that works unless you get very specific. Hope this helps.
All the best,
Tom
Adam did some nice big blue chips with coolant mist and cutting oil very thick and heavy very rough cutting what are you guys doing
Hi, Tom. thanks for the schooling on tool bits. i think i was making mine wrong all this time, my nose radius are huge and side loading my work pieces. your equation: what is the units or value of the "4" or is it a consistent??? thanks for the great videos. sorry about the stupid questions.
Hi Sam,
Four is an approximation of the conversion of feet per minute to revolutions per minute. Its an easier number to work with than 3.82 when doing work at the machine.
Cheers,
Tom
thanks
Excellent demonstration of the master's at work. Thank you
Hey Major Tom, (any relation to David Bowie?)
Thanks for the Chips Ahoy video. It is interesting how all the variables (cutter profile, spindle speed, feed rate, etc.) have such a profound effect of chip shape and color. Those last ones were getting pretty toasty! I'd love to join in, but the 13" Birmingham I am ordering (2hp motor) wouldn't cut the mustard, let alone a .800+ chip!
Thanks for the info. BTW, what grit grinding wheels do you use? The first one appeared rather hungry.
Regards,
Oxen Dave
Hey Dave,
This is Major Tom to Ground Control I'm starting up the lathe stepping through the door. And I'm floating in a most peculiar way
And the chips look very different today
Cheers
Tom
oxtoolco
Hey Tom . . . That was great! I laughed my ass off! (Now I have a major problem going to the bathroom!) The chips are never down between you and Adam (LOL)
Oxen Dave
Great video as usual. Important question, arduinovsevil is needing a sidekick for his fight against evil. Would you possibly consider wearing spandex tights with your underwear on the outside? I hope you don't wear some embarrassing underwear like Hello Kitty or anything.
Hi Cerberus,
About as far as I would go is a chain mail kilt. Would that work?
Cheers,
Tom
@@oxtoolco Made of Copper,for "Flair".
I was thinking short high degree tapers like you might use to machine a model rocket nozzle. But long propeller shaft tapering whould also be interesting
Want a tough test for your chip breaker, try some 17-4. I was turning some 17-4 a few days ago, and generally being lazy grabbed my toolholder that already had a nice cutter in it set on-center, however sans chip breaker. It shot out a long lethal ribbon that you wouldn't believe! Made me rethink what I was doing because I wanted to live!
Hi B2,
That 17-4 ribbon would slice you in two if it had a mind to. Those are some tough nasty chips.
Best,
Tom
Greetings- I was trying to point out to others who have light duty 3 jaw chucks and a short purchase
that they would have trouble making this depth of cut without using a tail stock. I have had it happen to me many times with a 12 inch atlas and short purchase. More likely, the part will move into the chuck as far as it can, and the part will slip in the chuck. I suspect your surface finish would be better with a tailstock. Jim
Hi Tom, thanks for the video.
Hi German,
Thanks for the comment and participation.
Cheers,
Tom
I have to ask, you have a perfectly capable surface grinder why did you not use that to flatten your cutting surfaces? do you want curved cutting edges?
A rounded nose ensures a single point of contact to the work, so a larger nose gives you a lot more play with you tool centerline I saw you made your radius bigger but why did you stop there? (most inserts have a much larger nose radius)
Why did you not cut a chip break behind the top cutting surface and rather load the tool until you had the chips break after hardening? I'm under the impression that hot chips equal tool wear, so a chip that breaks cool is a much better chip.
I'm a novice that hasn't touched a lathe in 20+ years but I want to pick it up again (retirement has its advantages) Just curious if my understanding is in line with your experience.
Hi Sy,
Setting up the surface grinder and making the edges perfectly flat does not increase cutting efficiency enough to expend the time to set up the angles and machine grind them. Offhand grinding was the subject of the video and well within the capabilities of most folks with a normal bench grinder. Thanks for the comment.
Cheers,
Tom
Some people worry at the raise of bit temperature during heavy grinding. Mr. James A. Harvey, author of "Machine Shop Trade Secrets" conducted extensive tests on the subject checking hardness of bits before and after getting blue by abusive grinding of cobalt bits and found no difference in properties or performance.
By the way Tom, I always wonder at the lack of a cooling system in your nice lathe.
I personally prefer full synthetic oil to cover both cooling and lubricating needs and avoid fungus, odor and other unpleasant features of soluble cutting oil.
Regards
Jorge
Hi Jorge,
Thanks for the information. You are correct that high speed steel with or without cobalt retains its hardness and functional properties even at red heat. When buried in a cut the fine edge see's a very high temperature indeed.
On the oil and coolant I prefer low volume methods. Slinging coolant around by the gallon is for production machines. Most hobby and prototype shops can get by with very minimal amounts of coolant and oil for most machining.
Cheers,
Tom
oxtoolco Very true. Also mist cooling is detrimental and counterproductive with Widia/Carbide inserts who due to thermal shock work best with flood. Many people by using a chuck guard use flood to extend tool life and help in chip sticking and removal during heavy cutting. Same in the mill with some sort of guard or cover to contain coolant splash. Fenner uses it when needed but of course he does production and as you properly stated the task and conditions are different,
Cheers
Is that a 6 or 8 jaw chuck? Interesting, do you have a video explaining how different it is to indicate versus a 3 or 4 jaw chuck?
Hi Deric,
Its a six jaw chuck. The jaws are not independent. They move on a scroll much like a three jaw self centering. Thanks for the comment.
Cheers,
Tom
+oxtoolco ohhhh OK so it's like a drill chuck.
Tom, what is that tool called @23:50 that helps you get your cutter on center? That's awesome. Did you make that?
+RumpLeINtiLINsKinnIN That is a tool center height gage or gauge. The top section is made by Hardinge. Thanks for the comment.
Cheers,
Tom
I realize this is 7 years old, but in the of chance you're listening - why grind so much off the side when you can just turn the tool post?
"It works when the lights are out". Because I make sure power is out before using the lathe...
Hello Tom,
subtitles disappeared again.
Sorry, I trouble you with it more
time goes slowly, but carries on
and now the best years have come and gone
you took me by suprise, i didn't realize
that you were lapping
Hi indoor,
Lapping, or honing. Abrading to produce a finer finish. Lapping is done on circular items as well as flat work.
Cheers,
Tom
How thick are the copper jaws you put on your vises?
Hi Michael,
Roughly 3/4 inch thick. This allows some resurfacing from time to time.
Cheers,
Tom
You can change feed rate wile spindle is turning on your Yam lathe? I don't think Doall lathes can do that.
What combination of wheel grit, wheel construction do you recommend for HSS?
Hi Jack,
Aluminum oxide one side coarse say 36-46 grit and one finer on the opposite side 60-80 grit. These are plain bench grinder wheels from McMaster Carr.
Cheers,
Tom
Would that be the Tom Bomb?
Tbom
thanks for the show tom...what grit wheel do you recommend ?.....
Hi Ray,
I have two grits on my bench grinder. Something like a 60 grit and an 80 grit aluminum oxide. Got them from McMaster. Thanks for the comment.
Cheers,
Tom
thanks for the mm conversion.
I cant help wondering if you have ever heard of 'Heat treatment' bcoz you get your HSS so hot when grinding it goes blue. I would go so far as to suggest that is completely the wrong wheel for grinding that metal, but, Meh, what would I know?