Chip Control Part 1
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- เผยแพร่เมื่อ 30 ก.ย. 2024
- This is a new short series of videos that Tom Lipton from OxToolCo and I will be making. It is about hand grinding your own HSS tool bits, and using them to make deep aggressive cuts in the lathe turning cold rold steel.
We show our own style of grinds, and make progressively deeper cuts while turning, ultimately finding out just what we can take off each pass.
This is something that should be fun for all of us, and maybe learn a thing or two about hand grinding tool bits, and how to make them perform.
Be sure to follow up with the OxToolCo TH-cam channel to see the next episode.
Thanks for watching guys, and we hope you enjoy!
Adam
Hey Adam,
Right on buddy! Nice presentation. I was surprised how good it was without any chip breaker. This is going to be fun! This illustrates the relationship between depth of cut, feed rate and cutting speed. Not something well covered in any book that I have seen. They are all interconnected as you showed so well.
Better go do my homework!
---Tom
Thanks Tom! I was really trying to set the tone for the videos, and hope I did a good job. I really wanted to show the grinds, and detail them so the guys would understand.
I'm looking forward to trying more grinds and see what kind of different they make on the cuts.
I'm looking forward to your video, and seeing how your tools and cuts may differ from what I'm doing.
As I said, I think this will be learning lesson for many of us, myself including, because I use the carbide inserts for most of my heavy turning needs these days. I actually really enjoyed getting back on the grinder, grinding a fresh tool bit, and making some heavy cuts.
Thanks for the response bud, cant wait to see what you have in store for us!!!
Regards,
Adam
Hi Adam...
Enjoyed and thanks for a great explanation on grinding the different angles...for me, lots of education!
Curious in your daily job what would your standard depth of cut would you dial in using carbide to just hog? And I would assume it is with flood coolant.
FYI...stopped by the betting window and placed a small bet on you (great odds) as a dark horse in the race cuz we got the old gray mare(stud) lining up in the starting gate....LOL
Chuck
Chuck, I'm glad you betting on the dark horse! LOL
I take some heavy cuts on the pacemaker at work, but when I say I mean 1/4"-3/8" a pass when rouging. Thats normally on the 1045 chrome rods. Ive had problems with tools moving or getting bad chatter if I go too heavy a cut.
Now on ductile iron sometimes I'll dial in like 1/2" per pass or more. The brazed on tools are great for those machining jobs. In that quick work shot on the last video I think I was taking a .400 cut, because thats easy to keep up with. >400 on the dial means one revolution per cut....LOL On the small lathe a take .125 each pass but high feed and rpm, because the dial is .250 per rev.
I just like to do whats easy to work with. if you push too hard you may scrap the rod and start over, and we dont like that do we.
Thanks for stopping by Chuck, keep an eye out on the odds for me. LOL
Abom79 this was a great video Abom i right after i finished it i headed to the shop to grind a new tool bit and take some cuts on my newly acquired Cincinnati 12 lathe. thanks for the awesome demonstration. i played with the feed and rpm and was able to take a .200 cut.
That may be an older lathe but it sure is a smooth sounding old girl.
Nicely detailed Adam, I am always keen on what grinds make use of all available horsepower, I mean .... your grinder has more horsepower than my lathe :-D
Also interested in seeing a fine finish tool grind.
Thanks Stan. I've gotten used to a few simple grinds that always work well for me, but this heavy cutting is a whole different animal. Hopefully we can keep playing with the grinds and see just what kind of cut I can take.
Before i question, i work as CNC lathe operator,
Why do you use so much cutting oil? Why not use Cut And Coolant in one to cut? Before i get to work on the CNC i was doing manuel lathe operating, and i never used cutting oil , except for using taps or make treat, but mostly used the coolant. Just dont be too crazy with it otherwise you get a shower(coolant). Would like to know some opinions about this. Love the videos btw, new subscriber!
Oil and coolant serve different purposes. Oil lubes the cut and improves finish quality, but does minimal cooling. Coolant cools the cut, but does minimal lubing. CNC can come closer to optimal settings, so coolant works in most applications. Smearing is a problem with stainless and aluminum that coolant does little to solve. With a CNC machine, you can increase the RPM to aid chip ejection, with manual you use oil.
Hi Adam. I'm a self-taught machinist, with honing of my understanding by Keith Fenner, tubalcain, and most recently you. I'd always had trouble hand grinding tool bits, but this video suddenly made it all clear to me. Yesterday I had the need to make some Delrin bushings on my Grizzly 7" X 12" mini-lathe. Armed with the knowledge from this video I ground a HSS bit and ended up with a mirror finish on my project. Thank you, my friend, for sharing your knowledge via TH-cam. I hope you're aware of how many of us you are helping to progress in the craft by your videos. Thanks again.
Hi Adam, that was a great way to demonstrate the grinding and use of the tool, I like the fact that you didn't get carried away with a lot of fancy talk and angles, and you eased into it, start simple and add a little rake as you went. Awesome results, thanks for another great video, I know I will learn a lot from watching this series progress, can't wait to see what Tom will show us.
Thanks again buddy!
Mike
Thanks Mike! I don't use the hss to make heavy cuts very often anymore, so I think this will be a learning experience for myself too.
I work in a paper mill maintenence machine shop here in Maine and the company is really good about buying us tooling like inserts and holders. We have a ton of the old stuff kicking around on the shelfs and HSS bits everywhere. I've always stayed away from them just because we have carbide at our disposal but man, after seeing what your doing with it, I'm gonna spend some time making some up and trying it.
Great video. Once you get through the stock removal, give us a little on getting a better surface finish when things are being difficult.
Thanks David. I'll touch on that in a later video.
Hi Adam,
Very good explaining, easy to keep up with you. That's a solid lathe you have here, not slowing down very much and no audible shimmer even diving .375" in the metal. I've got the new lathe coming in today, hope to be able to push it more than my present machine.
New stuff from some of my favorite machinists makes it a very good day...!
Thanks for your time,
Pierre
Hey Adam-
Sweet video. That lathe is Godzilla.
There's gonna be a lot of stalled machines, smokey shops, and worn grinding wheels because of this video!
Good stuff!
Alex
there is one thing, i was wondering on your experiments. the smaller the diameter, all do you run at the same rpm the FPM passing though the tool is less as the diameter gets smaller. Then it would be hard to compare the time you cut from the new shaft (full diameter) and the small diameter after it was cut 2 inches. All cuts should be made at the same diameter. Chiers!
Nice video. I need a lager lathe. My 11" Logan has limits.
Thanks.
Really enjoyed this video. Very interesting to see the changes that the various grinds, feeds and depth of cut make in the reaction to the cut. It gives me a better idea of what I can expect from my feeble attempts at cutting. I've been far too conservative and will try to summon some bravery and try more of everything. Thanks Adam. Super.
Keep working at it, and trying different cuts, because if you dont, then you wont know what your capable of turning on your lathe.
Thanks Jim.
When I read "Chip Control" I expected plastic sheeting, magnets and lots of vacuum suction.
nice one, Adam.This really explains a lot.especially since we do not all have an array of carbide inserts in the drawer to choose from. i liked your last video as well, because, in fact, it is the most interesting to see what you guys come up with when things are not working out straight away. Thanks, keep the machining problems to be sorted out coming.
That was some big Cuts !!!..All that Smoke rolling out of the shop I was waiting for the firetruck to show up
Impressive to say the least, learning all the time, great video for beginners.
I enjoy watching you play with the tool and talk through it. Really shows your expertise.
mmmmmmm
Thank you Adam 'You are showing the stuff hobbiest and everyone are craving to learn.
Hey Adam,
Excellent "chip control / deep cut" demo! Clear, easy to understand, and great step by step instructions. I am really surprised you stopped at .750" I get the feeling your saving the best for later....
Great job man,
Ray
Thanks Ray! hey I can pull out all the stops in the first video man, I gotta work up to it! LOL
Hey, its time to see what the Grizzly can do!!
Man it would sure be nice to have a machine that rigid! I am getting chatter and belt slipping at a 0.075" cut. I guess you can only push a bench top lathe so hard.
LOL
Nothing like a good old monarch gear head lathe
Thanks Adam!
Just bought my first lathe recently and this video couldn't of came at a good time. I think I'll order that book you have.
Thanks again
On my typical tool, I run a bit of side relief, and somewhere near 10 degrees of side rake. Back rake is fine but limits sharpening times. Pretty much exactly how you made yours. Never tried a chip breaker, normally they brake nice. Perhaps I should try one. I learned my lesson at school like you did in with the first cut, I was running to fast (within the formula, but not at the crazy feed rate I was running.) Big blue chip, didn't curl, burnt up my cutting tool. Slowed it down, and the chip broke. I guess the hot steel is more flexible and doesn't break like a normal chip would.
thats not a chip thats flashing material
I'd be keeping my sleeves pulled down covering my Aces just yet. you never know what will come out of the Cali-coast dude! Did I say dude? ;-)
Looking forward to this one!
Colin
I'm patiently waiting on Tom's response Colin! Thanks buddy!
Long time due but your health goes way before you subscribers and the fan was not that loud at all.
THANK YOU!! I have been wanting to see someone grind and see it from start to cut. I have a ton of HSS and some MoMax Cobalt and I'm finally getting good cuts. Just need to get a better grinder, mine has seen better days.
I think this video series will help me a bunch! I really need to learn more about this. I have a question. My lathe is 220V single phase. I can never get the kind of finish you get on your lathe. I have heard the 60 cycle motors will cause a vibration and you just can't get the finish that 3 phase machines will produce. I am assuming your lathe is 3 phase. Will be watching for the next videos from you and Tom.
Well Steve, I cant say that I have experienced your problem, because I have only ever used 3 phase powered machines. But I can bet you that with the proper tool,feed and speed, you can achieve great results no matter what lathe you have, or the power supply.
You could be on to something here, I have had similar difficulty with small single phase lathes, but I assumed that it was because they were small, and lightweight,now I have a Colchester Student in 3 phase I never have a problem.
60 Hz or 50 Hz by itself will not cause mechanical problems.
I would not say it is single phase or 3 phase causing poor finish except that in general 3 phase will quite likely be a bit more rugged with better bearings than a consumer grade motor. If you have industrial single phase it should be a toss up. Check out your mechaical drive system and components. Run motor disconnected - it should be pretty much vibration free just windage noise and no squeel. If squeel or vibes get new bearings and get good ones. Check motor temp if you can when loaded - hard to do sometimes I know too well. It should ratate freely by hand and do so for 10 or 15 seconds. Basically same procedure for rest of drive train. Clean machine as you go and lube stuff up well.
OK that is my experience from 40 years in maintenance (mostly motor control)
If you are sure machine is all good then it is practice and more practice. For sure I need practice. Do NOT do as I am tempted to do and rush on cutter grind or put it off for just a bit more.
Dan Bentler
hello i have a 14x40 chineese precision lathe so they say lol and ive taken .200 of of the diameter no problem. only did it once to see and i actually did it by mistake so anyway i have no problem on my single phase 220 lathe to make mirror finishes so i dont think it matters single phase or 3 phase in my opinion.
very interesting, thanks for sharing this information!
Why putting a radius at the corner of the cutting edge? I never did that.
leaves a cleaner finish. If you look at just about every bit out there, they all have a rounded cutting edge. If you have a sharp edge without a small radius, it almost leaves a threaded look on it. Unless your feed is slow
to have a better surface finish
Adam: smile more!
great video a lot different then woodturning tools adom.
Great video Adam, I like that you are using a lager bit to show the angle of the grinds are. I'm use to grinding on 5/16 HSS bits so the angle are a little bit harder to see. I was surprised when you cut 1/2 but then you went for a 3/4 bite. I really didn't think the HSS bit could handle such a big cut. Also showing how you can simply adjust the RPM or Feed and the angle of attack to get the chip you wanted. Very educational, thank you.
Matt
HSS tool bits are surprisingly tough! In this age, many people rely on carbide for much of there machining needs, but if your not in a big hurry, or just dont have fancy tooling, HSS will do the same thing. Its all about the grind, feed, and speed.
Thanks Matt.
Thanks for the vid Adam. I really need to start grinding my own hss tools, you video was a great explanation.
I can just see it now, Elena sitting in the kitchen watching the smoke bellowing out the workshop door with her finger poised over the Halon dump remote.
Great video Adam, I don't have a lathe yet and always struggle with the diagrams I see of grinds in relation to what they are actually doing both to the tool and the cut, and a lot of stuff clicked after watching this video - especially how simple adjustments in spindle and feed rate make with no changes to the tool. Looking forward to seeing what tricks Tom breaks out in response, maybe he will have to resort to Autocad ;)
Autocad for a tool bit?? That would be a first for me. LOL
I can;t wait to see what Tom has in store for us all!
Thanks Steve!
Cool video on that topic - there's nothing like heavy cuts and steaming oil - the heavier the cut, the more the fun!
Not too many videos leave me thinking for hours on end, but this one did it. Just wonderful. Thanks for posting.
Tom (Australia)
Thanks Tom!
another thumbs up Adam, I only say holy smokes. I just hope you two don't break
anything. All our lathes were born with HSS so I'm stickin with it...
Im going to follow this series closely. I learned a lot just watching how you stone your bits, and the effect feed rate and RPM have on chip curl. I'm only a hobby machinist and may by I'm doing something wrong, but I always seem to get a much better finish with HSS bits over carbide with almost everything I turn. So I used hand ground HSS bits almost exclusively.
Hi
Adam
Really good video
I grind a lot of my own tools
Be interesting to see what Tom comes up with
Regards
John
I can't wait to see Tom in action!! Thanks John.
Thanks Adam nice one
Louis
Could you see down to the other end of the shop through the smoke? LOL Great vid. Thanks
It gets a little foggy in here sometimes, but the fans help push it around. just keep a window and door open so it can vent out. No problem.
Adam, great demonstration of what good old HSS can do, Thanks for the videos, I enjoy them,,, keep them coming ,, Harvey
Hey Adam did you open the PANDORA BOX that Tom Lipton send to you?
I did. That was in Saturday Night Special 17 parts 1 and 2.
Adam, I think smoking would be healthier than breathing all that oil smoke; it certainly tastes better than burnt oil.
Hope you and your family are above the waterline down there in Pensacola and everyone is okay!
All good around the Booth home. Thanks Robert.
Nice video Adam, there are optimal grind angles, rakes, relief, and radius for material and desired speeds, and feeds... There will be plenty of learning in this series... Thank you guys for sharing! :o]
O,
Nice instruction and a "simple" way of grinding bits. I can only imagine the heat produced based on the smoke on that 3/4" cut.
The more I watch you on that Monarch, the more I realize just how wussy my lathe is!
Thanks for the video and the lessons that you give us (for free even, LOL). I love watching you and the big Monarch making steel behave.
Wow! That is the best explanation I have seen yet! It makes perfect sense to follow the curvature of the grinding wheel. I noticed that my grinders' tool rest does not adjust higher than about 1" under center. I will be making a new bracket to correct that.. Thanks for another great video!
Adam, thank you for a great video. I know this is your first step in trying to make a "teaching" video and you did a good job of it. Don't worry too much, while you might not be the best presenter your work and attention to detail is excellent. You'll get better the more you do.
It was great when you put up the still images from the book to show what you were talking about. You might want to consider putting those to one side or the other instead of smack in the middle.
What I got out of this video is not only how to grind tool bits but how to listen and see what is happening. How to adjust the lathe. Please put explain a bit more about what you are observing that makes you feel that a chip is good or bad. What is it that makes you want to change speeds or feeds.
Thanks again for all your hard work.
Perfect time to ask about body positioning on the lathe Adam
Is comfortable always safe?
damn, Adam you brought out the BOOK,
Great demo of what can be done with a very simple tool grind. It will be interesting to follow how much performance can be improved with your optimization of it!
Hi Adam, Watched Tom grind and I liked both yours and toms. Your teaching me lots . THANKS M.K.S.
Hey Adam,
Some SERIOUS hoggin!! How many horsepower is the Monarch -- 25? Your grinder must be a good 7.5hp. Is everything 230volt or 460? (3 phase, of course.) Just curious. Anyway, it was very interesting and I appreciate you sharing your expertise. You should get together with Don Cossitt and send smoke signals to each other! LOL Was that what the sirens were for . . . they thought your shop was on fire? :-) Thanks again!
Regards,
Dave
Dave the Monarch is A 5 hp GE motor, 230 3 phase. The pedistal grinder is 2 HP. I checked the Monarch a while back because everyone was asking me after the facing videos. it seems small yes, but works well.
I like a smokey shop! Helps make it smell like a machine shop!
Abom79
Adam,
When I serviced and installed professional woodworking machines, most shapers had a minimum of 7.5 hp @ 230V 3ph. The sanders that used 60" wide sanding belts has 25hp motors. Some were 460v 3ph. When having to trace down electrical problems on these you had to have the power on. You had to be super careful when working on them . . . one wrong move and your ass was toast . . . nice golden brown!
Dave
a little ruff starting out with coloring , but a nice presentation.of speeds and feeds
Really interesting video. I'm surprised how much you can (could) take off in a single pass. I wonder if you could go slightly deeper with a square on cut. When you were cutting at a depth of 500 with the lead in angle your cutting face was more like 510 to 520 depending on the angle.
Hey Adam,
This is an interesting series. It's great to be able to see "what if". I'm learning a lot and finally beginning to understand all the angles needed on a tool bit.
Bill
great show / school thanks for all your videos ..from Ireland
Adam,
That was awesome. Thank you for sharing your time and talent! Looking forward to both your and Tom's upcoming videos!
Chuck
Adam, I hope that the flooding in the Pensacola area has not had an adverse effect upon you.
Ok Adam, let me chew on this one for a while
That's a tonne of info buddy, a tonne... Holy!
Very good tech video I enjoyed it so keep doing what you did
lots of tips and tricks :))
Manny
As a beginner, this has to be one of the most informative video's I've seen. I've got some 5/16" tool blanks on the way and I'm looking forward to getting a tool shaped. Thanks for the excellent presentation!
Wow those are some chips, looking forward to the next installment.
hi
was wondering ,,,I seem to get trouble parting...was wondering about a vid on parting a piece of 3.5" steel? :)
Maybe we will add a series on parting.
Abom79 thanx enjoy u and all ur buddies vids...great that people take the time to do them
I do lots of maching but partin gets me at times??
Terry
I'm thinking that you need a new book, not that there's anything wrong with old fashion, I just learned all of my information from "The Machinist Handbook" the only problem I have with it is when they make a new version it adds some new stuff to the new version and then I removes some stuff from older versions so you might need to look in older editions to find what you are looking for. But I like it, it covers everything, equations, diamond grinding, tapping threading, etc....
I have many old books to read from, and some are even semi current. I do have the 7'th Edition American Machinist Handbook, its great to read through.
Abom79 Love all your videos man...thanks for the inspiration. Have you had a chance to look at any of the newer editions of Technology of Machine Tools? Looking to get one and saw the newer editions and thought I'd ask what ya thought. Thanks man and keep up the good work.
Man your very smart with this, keep up the good work.
respect you
Ever had your chip-pan catch fire? :)
I have caught wrags on fire before because of the hot chips. I even has caught the cutting oil on fire inside a bore a few times. That interesting to see.
Great idea for a video man. Be good and keep doing what your doing.
Thanks Adam this is informative and interesting.
I would like to see you take 3/4" dia cut on your victor LOL im just messing with ya adam this is an interesting vid as i was going to do a similar video using my Hendey lathe which should be able to come close to taking 1/2" dia or more ....its all about the grind
I don't know if the Victor would handle that kind of cut, maybe in low gear. I have tripped the breaker a few times turning with carbide inserts on it. But your right, its all about the proper grind, but also feed and speed.
As Keith sais, sirens are a good thing, someone has a chance.
Adam that was great introduction to the topic and most helpful. Lighting, photography. explanations, demonstrations and editing all excellent.
However a few questions / comments: Is all tool steel the same? Were you using a particular manufacturers special or were using a certain a grade? I think you used a trade name / description to identify it?
Please explain what wheels your grinder is fitted with beyond the coarse / fine standard you used - re are they something special in some way?
What is the oil you were applying liberally?, are you using it for heat removal as well as lubrication?
Whilst I understand the issue of rotational speeds of the chuck you were using [i.e. RPM] I don't understand the figures you used for feed speed. Please briefly explain.
Dan, good questions that I knew would get brought up. I was using the Crucible Rex 95 grade of tool steel. I always thought it was just another general use HSS but after some researching I found that its a little tougher. I have some other ones I'm going to dig out and use to, and maybe I will talk a little about the different grades. I'm no metalurgist so I'll do my best.
I'll touch base on the grinding wheels also.
The cutting oil is old school sulphur based dark cutting oil. Its great for just about any cutting needs in the shop. Its not used to remove heat, but to lubricate the cut.
The feed rates are given in thousanths per revolution, meaning each time the chuck rotates on time, thats how far the tool advances along the workpiece.
I'll touch base in that too in a video for ya.
Thanks Dan
Man, this is some real meat and potatoes learning. Im q
Good show Adam
I am glad you started this series on cutting bits.
Thanks Adam
I keep finding more videos, this is awesome man. :)
Thanks for the step by step approach and explanation as you go, so even as a novice I can understand.
One thing, you have a Very powerful and rigid machine and while this information is excellent for the pros with these machines I hope one of the other fellows will demo on the smaller machines and the problems we face with less power and rigidity.
Thanks to you all for taking the time to develop these videos.
HH
There has been several guys posting videos of making cuts on smaller lathes. Check em out!
Nice video - and very useful. Can't wait to see Tom's and your follow-ups. How long will that edge hold up to the heavy cuts?
It depends on the material and cutting parameters. In the cold rold steel it should hold up well for lots of cutting.
the couch potato, it seems that you are saying that a "short chip" gives you a better cut then a "long chip"?
You want to break a chip, not have long continuous chips. When they curl over and break off, thats called good chip control!
Abom79
Ahh, Thank you ;}
I worked in the 70's in machineshop... hss is a great stuff, but producing a decent output brazed carbide is very great...
also some steel like C45 was very hard to work with hss... I was comfortable the 5/8 or indeed the 3/4 bits.. for parting sure I used 5/8 at least..
anyway, good to see still people grinding by hand..grizzly has for 20 bux diamond tip dresser...
Dude, I see so many guys taking HEAVy cut using OIL !!! Water soluble (Oak Leaf or Trim for starters). Yeah, Oil will give you a better finish...maybe. But Water soluble will cool the part and the tool, and make your finish more predictable....not to mention your life span.
So get your coolant pumps running and go with some water soluble.
Nice heavy cuts with HSS.
Great video. Great instructor also. I learned quite a lot from your explanations as you machined. Keep up the good work. I wish I was closer, you would not get me out of your shop.
From the sounds of it your not the only one who wants to hang around! LOL
Thanks William.
Instead of playing with the feeds and speeds try using.......SFPM x 12 = Pi x Dia = RPM
Hey, whats your ceiling height in that shop? The place looks tiny, but then you realize its a good sized shop just stuffed with big ass tools! I need to expand, but $$ is always tight. Your place makes mine look like junk!
Your cut at 31:30 is exactly what I do with HSS on my lathe, within like 10 SFM (I normally have it just a little slower in RPM for same part diameter) and exact same feed. Roughing cuts quarter to half inch off the diameter, finishing cuts are a bit different but you know what I'm saying.
Keep on swarfin' buddy, I love your vids!
Adam the best I have ever done on my Myford 3 1/2" lathe with 1/2" HSS is a cut of 1/8" (thats a quarter of an inch material removed) using a round nose grind with plenty of back rake ground in and the top slide replaced by my special cross slide tool mount to get rid of the vibration caused by the compound (top) slide dovetails. I don't think that is to bad for a machine (born the same year as me) of such small dimensions. Enjoying seeing all of your videos, thanks for making them.
I think I've done about .15 on my ml7, with a the cross slide on, hand cranking, taking a cut out of some 2.5" 1045. I felt really bad about it lol. Are you in North America, what are you doing for power? I've got a big transformer, running the old English motor at 60 hz.
I am in England running the Super7 on three phase power at 240volts 50 Hz with a converter. I guess you like your ML7 as much as I like my old machine. I don't push it hard and resist the temptation to overload it when using modern carbide inserts, so they tend to last and last, but I have noticed recently that several are wearing out, so I am trying some really sharp high positive rake ones to see how they work out and what sort of surface finish I can get, early days yet as to which I like the best.
I bought a Chinese mini lathe first, and while good to learn on, it always found a way to be highly annoying. I saw the Myford for sale 5 km from my house and in near mint condition, which is highly unexpected as I kind of live in the boonies, as far as industry in Canada is concerned. I ended up with a machine made in 1971, 25 years older than me (I've spent my money on tools instead of a first car lol). I love my Myford, but I'm always very gentle on it, partially because I'm terrified of British parts pricing and shipping, but mainly because I just like hearing it hum away making small chips. What kind of inserts are you using, I've tried cheap TCMTs with little luck on steel. I'd love to hear more about the high rake inserts though.
Hi Fraser
The tool I am currently enjoying using is the SDJCR 07 with a 10mm shank, supplied at a very reasonable cost by J B Cutting Tools web site jbcuttingtools.com it fits in the dickson quick change tool holders nicely, if you have the standard four way toolholder then you may be better off with the 8mm shank version, if you have the standard clamp toolholder then you could use any size shank up to, at a push, 16mm I personally would select a size of shank that fits in with any ideas you may have for tool holding in the future, the 10mm shank is adequate for the Myford. Anyway, my new tool came with a silver coloured tip, which is sharper than the gold ones and has a really deep chip breaker formed in it, the web site shows them. They will not tackle tough material or metal that has been heat treated and if I were say cleaning up welds I would use the ordinary ones, but for fine cuts and as you say a nice humming along chip they seem okay. It's early days as far as finding out about long term wear on the silver tips, so bare that in mind if you decide to try one. I was into motorbikes at your age along with machining, the first really expensive (to me at the time) purchase I made in my life (I was still at school) was to buy an old lathe.
I'm a "hobby" machinist and could really have used your videos 15 years ago when I started using a lathe and vertical mill at a local vo-tech. Watching someone who knows what he's doing and makes it look easy is inspirational.
I have a question though. Being self-taught, I also have every machine tool book I could lay my hands on, dating back to the early 20th century when the tools had overhead belts and the machinists wore long sleeves and ties. All of those books show the sharp back rake built-into the Armstrong tool posts. I suspect there was a reason for that. What's your opinion? As I've observed the back rake is built-into the inserts you use. Did you do the same thing with the chip breaker? If not, I have to wonder what difference it would make.
One final observation is that machinist friend of mine told me to stick with carbon steel except for work on stainless. He told me that for my purposes, the bits are easier to shape (grind) and the performance is good.
Adam,
What works for me is a tool with a radius bottom chip breaker 1/8 to 1/4 inch wide.
The width depends on feed and speed you are running.
The top face honed with a couple thou flat will cut clean and make nice curls.
The flat strengthens the edge and carries heat away faster.
Chip weld will attach to the flat and help protect the edge too.
When you are making clean curling chips
With a light straw color the tool will last a long time and get her done fast as high speed will allow.
Regards
Kap
Hey Adam, I fab a lot of custom parts for antique cars and AHRMA motorcycles. I love the videos, been watching them at night(and falling asleep to your lovely southern baritone. lol) just picked up the book in the video (8th ed.) can't wait to improve my lathe skills. could you do a video on how to turn rounded objects? i have turned a few with my own custom HSS grinds and have had good results, but could be easier, safer and faster for sure. keep up the good work.
Awesome video explains so much just by showing different settings. Thank you. I was thinking as your cutting the diameter down, this changes the the chip curl rate required. This is my thinking.... as diameter decreases, chip has to curl more is same amount of time (tighter spiral). Is it a good rule to slow your feed rates as the diameter decreases. ----> giving more time for chip to curl?
I was about 18 years old in in early 60's and was taught to use a similar HSS bit, (older turt lathes) and we took off 2 pieces with a boring bar system where the HSS was protruding either side of the bar, and probably close to 3/4 of an inch either side of the bar at the same time. Which would mean I was taking out 1 1/2 inches of metal making bushing for saw mill chains.
You should see if you can duplicate that some time which I would like to see if you can do it.. but the feed was slower and we used a steady flow of coolant.
Probably several others would like to see that done too.
So I claim to be no machinist. I’m an engineer. However I do feel it important that I know basic machinist skills as to better myself as an engineer. Tonight I was turning down the OD on a piece of aluminum round stock to make a bushing. As I decreased depth of cut the chip did not break but as I increased it did break better. Why is that? I always thought I’d seen the opposite. Obviously changing speeds and feeds can easily fix this problem however my curiosity for trying this single solution I thought should work was keeping me from doing so. Again. Why is it that with a lighter cut the chip doesn’t break but the heavier cut it broke (not great but it curled them off after a couple rotations).
Very interesting video, what you are demonstrating can normally only be done with free material, i,e, at work, to cut up large lumps of experimental mild steel is too costly for the average home machinest. I only ever use HSS tools, I find the insert chip so easily. one thing you can try is grinding the whole cutting front edge of your tool back by 3/32" or so to give a very handy radius cutting area when facing off, you can always set the tool around if you need to face of larger Dia stock, I find this works very well. Many thank for posting this.
Thanks Adam. I'm pretty unpracticed at grinding and have to rely on luck to get and edge, so I think this video will be helpful.
I pay a lot attention to the sound of cutting, but I'm not really sure where the cut sound is generated. Is it the metal shearing, the tool bit vibrating, or the chip vibrating?
Thanks again.
121 rpms .250 thousandths depth cut, nice! haha curlies on the shoulder cut, lol, great video slow the feed rate fast curlies it looked like the rpms went up awesome experiment good experience for when get orders for parts or whatever beautiful shoulder cut 121 , 158 it looks like there got a chip stuck on the bit that is some serious hot blue crazy thick chip curls