Grinding HSS Lathe Tools | Beginner Tutorial
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- Опубліковано 27 тра 2024
- Cutting Tool Geometry Chart: 0.academia-photos.com/attachm...
G'day everyone,
I've recently bought some new HSS tool blanks for the lathe. My intention is to grind them into lathe tools for various types of cuts and materials. Since I was already going to grind the tools, I thought it might be useful to film the process of how I decide how to grind the tools for different types of turning operations and materials.
In this video I will go over some basic tool geometries (rake angles and clearance angles) and tool shapes that I have ground over the past 6 years. This video is intended as a beginning introduction to tool grinding and will allow beginners to understand the reasons why tools are shaped the way they are. I will be using by bench grinder to grind the tools into shape.
I hope you enjoy the video, cheers.
Timestamps
Intro - 0:00
High Speed Steel - 1:03
Grinding A Brass Tool - 3:27
Grinding A Positive Rake Tool - 8:02
Aluminum Chip Breaker - 10:25
Steel Chip Breaker - 11:41
Back Rake Angle - 13:01
Right Hand Tool - 14:08
Left Hand Tool - 15:34
Form Tool - 16:10
Boring Bars - 17:30
Lathe: Sieg c3 7x14 mini lathe
Mill: Sieg x2.7l
#machining #DIY #lathe
![Making of: Small precize lathe tool out of broken drill bits [M4 internal thread cutting]](http://i.ytimg.com/vi/k2a9ywCEK_A/mqdefault.jpg)
![Making of: Small precize lathe tool out of broken drill bits [M4 internal thread cutting]](/img/tr.png)
I bought a used Kennedy machinist toolbox a few years ago and one of the drawers was filled with hundreds of HSS tools. Most already ground, with plenty of life left and dozens upon dozens of blanks to work with as well. A lifetime's worth of tooling. It's allowed me to study the grind on the existing tools and plenty of material to better learn to grind my own.
Grinding the tools brings back memories....
Can't remember how many times I had to re-grind because my teacher found a flaw. If you finally got his approval you needed to use it on the lathe for a test cut.
After handing in the work and tool he would mess it up so no-one could re-use it.
We learned to do a quick switch after turning and before handing in the work. We needed to hand him the tool as far from his desk as possible (that's where his glasses were). He didn't checked the tool, he just picked up an airgrinder
We had to make 6 or 7 different tools so with 7 classmates we all made just one. This trick saved many hours of re-grinding.
Remember, Grasshopper, that you may think you have fooled me today, but there are many tomorrows!!!!
Nice😂👍
After watching so many videos, some people are just gifted at explaining and teaching. Thanks yet again for another clear and concise video on such a murky subject. I kid you not, I just watched 5 videos that defined each geometry but no explanation why they are there.
Years ago when I was doing a lot more custom tool-making; I was using high-speed steel to make Precision Form Tools.
Now since I work a lot with diamond tools, I make "All my form tools from Tungsten Carbide." I use fine grain tungsten carbide and they rarely break when in use and a form tool will last for years. Geometry is "King" when making any tool.
Thank you for your exclusively lucid/clear and highly appreciable contributions - please keep it up.
I bought a South Bend 9" C lathe from an old guy who retired and it had probably 10 lbs of this HSS, now I need to practice making these.
Whilst I know what needs to be done to create a HSS cutting tool seeing it explained in this way without all the "Math" involved makes me more confident in having a go!
I have ground custom cutting tools for jobs but mostly they are used once and then reground for something else.
My go to tool however is and will always be my diamond tool holder. Expensive to buy but more than paid for itself in usage.
Keep up the good work!
Thanks for posting. I dwell more in the Woodturning world where we sharpen HSS a lot. Many of us move quickly past the crap grey wheels on to the blue wheels, then white, finally ending up at a CBN wheel. As you probably know these are designed for HSS and are better than diamond. No silica dust, they don’t wear out for a long time, easier on the steel, and maintain a 8” diameter always. I find a 80 grit for shaping and a 200 grit for sharpening are a great combination. I’ve found your content to be interesting and educational. Thanks again.
Great sharpening technique, very clear and easy to understand.
Extremely helpful and interesting. I'm getting blanks and just the odd carbide bit holder for threading. Thanks !
Even more informative than usual, which is saying something in your case. Bravo!
I've been at this game for many years, thanks to this video, I have learned quite a bit. Thank you!
Been doing this a long long time, as my father and grandfather before me. I think I have two almost three tool drawerfulls of tool bits and drill bits and countless more around the shop. I grind and sharpen all by site sound and spark as I was taught. It's a dying art and I have to admit inserts are the go-to now. But I still use my HSS now and then. Great vid.
Inserts?
Excellent video. Thanks for taking the time to make this.
That was excellent. I learned a great deal. Thank you.
Great video one suggestion if I may when chopping the tool to amore proper size if you cut the blank at 10-degree instead of straight with the cut off tool you will save time and steel because both blanks will have a 10-degree clearance built in so is less material to grind
Thanks for the time you take to explain other how to!
That didn't occur to me but that is a great piece of advice
Oh who's a Cleaver clogs,well though of mate, sometimes it takes a different set of eyes and thoughts to see different solutions to things, lots easier to get the angle right if you can set up and hold in jig for a run of first angle cuts, then will have ready multiple semi blanks to hand, all at the right start point, think lm gonna work on that and make a mini cut off jig to bang out a number cut with the right first angle, will need to make sure its dead right first and they make some really thin cutting blades now that last well so guess what l will be starting to work on this weekend coming, have always wanted to have this mistic art explained in laymens terms, most people who can do this kind of thing try to make it sound as hard as they can lm sure to stop you from trying and making them selves the wizard of the tool making
Good thinking Bat man.
Watching this and how it has been explained has given me the confidence to have a go so fingers crossed and thanks for the indepth breakdown and explaining it for us. Great vids bud, keep EM coming.
A good no nonsense tutorial video Thank you.
Always been worried about grinding my own tools but now I feel a lot better about giving it a try.
Thanks and a happy new year to you.
Great vid as always. We shared this video on our homemade tools forum this week :)
Great info, thanks for sharing.
Thank you finally someone showing and explaining in a way I understand I have been struggling with grinding bits and this video and how you're explaining it is so very helpful thank you so much
I appreciate this lesson. I'm saving your lesson for reference.
Very interesting video. Thanks!!
👏👏👏👏👏
Excellent explanation thank you.
Thanks for the useful tips!
I'm really old school.... I still grind everything by eye. It's been working for over 40 years so I reckon I'm going to stick with it.
Maybe my angles are not optimal but I probably have 500 + different HSS cutting tools for every possible machine lathe operation in various sizes. If it ain't broke.. yada yada.
Nice video though. Well done, you!
Edit... I do all my drills by eye too... if it ain't broke. I see new fangled jigs to maintain angles but it seems to work no better than my eye and requires setup.
Oh... new sub here. Soothing to watch.
Do you prefer hss and grinding over carbide inserts?
Perfect video!
Thank you, sir, the video was very helpful, appreciate your time !
Very nice and comprehensive tutorial. I thoght for sure that the hardening would be ruined and just assumed ju had to have som sort of cooling fluid when grinding. Looks easy now when you show it. Thanks!😊
Good explanation. The dremel mini tool can improve the cutting edge with a chipbreaker.
Also a set of diamond files can smooth out the cutting edge into a radius, to improve surface finish
Excellent work.
Thank you! Cheers!
That was great. Thanks.
Very helpfull video!
Thanks. That helped me a lot 👍
Wow thanks for the detailed info really helpful for a beginner like me
Glad it was helpful
Awesome, video 😁
Good job sir
The extra compound angles at the end usually trips me up. So I just get carbide, as I would like to make things, not the things that make the things. I've watched more how to shape hss videos than I care to admit. None seemed to resonate with me. However, your explanation seems to hit home. I think I'll try to form some hss after this. I have a desire to use hss on aluminum. It is supposed to be REALLY great for the finish. Thank you for the video!
Making tools to make tools is the most fun.
well done
Great video mate. This Old Tony also has a great video on this if you or anyone else wants to look into
Great video dear:))
Thank you! Cheers!
thanks much.
Great video, any help on grinding a boring bar tool?
When using HSS cutting tools there should never be any change in the colour of you chip. The more colour change the faster your tool dulls. Same for drilling. Once the chips start to change colour you are producing enough heat to soften your cutter. Shinny chips make a happy machinist.
I think I was pushing a little too hard on that mild steel. Not the nicest stuff to machine and I had to take a deep-ish cut to get a half decent finish and wasn't paying attention to the chips. I had a much better time machining that cold rolled. Cheers
i forgot to mention it was a great video, thanks for sharing
No all the heat should be coming off in the chip . It's now a lost art .
My understanding of back rake is that it is the equivalent to top relief when the tool is facing and cutting on the front edge rather than the side.
That might certainly be the case, and it might me more critical when the nose radius gets bigger. Of course it's up to you to add this but I've always gotten away with zero back rake. Cheers
@@artisanmakes Horses for courses, I have seen old instructional documents from pre WWII that had no back rake and I think they used a left hand tool for facing instead of the front of a right hand. Kept it simple but meant tool changes for facing. I have been using a Diamond tangential tool holder that negates these issues with a great deal of success. Thanks for posting, picked up a few tips.
Just wondering if my high school shop teacher had to high of expectations when he made us make our own tools on a grinder with no jig while also learning the grinder for the first time. We only got 2 45min classes to learn and finish are tools to stay on schedule. Plus his teaching method was to just demonstrate then sit down and tell us to help eachother with any problems. We made the crappiest ball ping hammers that quarter.
We must have had the same high school shop teacher then XD
Thanks
Great video, thanks for taking the time to make the video. Question: You mentioned DRESSING the grinding wheel, how is that done and what are you using to dress the grinding wheel? Thanks
look for dressing stone for grinding Wheels
it is a way to sharp your grinding wheel
Good ❤❤❤❤❤❤
Great video! Should I use oil when honing the HSS bits on a diamond hone like yours. Thanks
I would say so, the instructions that came with mine said to use a bit of light oil. I use 3 in one oil for most of my honing and it seems to work fine.
Can I use my band as to section the HSS, or is it too hard? I used to operate a large shipboard lathe as a machinists mate in the Coast Guard, but that was back in the ‘70s. I used to grind all of my own tools, as they didn’t have the pre made brazed or index tools back then. Just getting back into turning, and this is a good video to re learn the process. Thank you
Thanks for another well made video! For the steel chip breaker, is the 10 degree side rake after the chip breaker needed? I’d assume the chips curl at the chip breaker and the angle after that wouldn’t matter much, for example if it was a flat zero degree. Am I missing something? If so what purpose does it serve?
To answer my own question: I assume it is not needed. It’s there because it was made before the chip breaker was made, and only shows that the chip breaker has the same angle as the cutter had before the chip breaker was made.
hello from iraq well done
I wish I had seen this video in 1978 when I first used an engine lathe in college.
Have you ever tried a white grinding wheel? An old friend that was a machinist had one an it ground hss like nothing.
they sell small boxes of quarter inch HSS tool blanks at harbor freight for $5 a piece. i have a mini lathe so i just got a couple of those and im set basically
👍👍👍👍👍
Cheers for that. How does HSS go on 4140 in the little lathe? That is the material I struggle most with carbide in my small lathe. I have not been able to get it to break a chip, best I can do is endless tight spirals which are manageable, but the speed and feed range it will do this is tight, and close ot the maximum depth of cut I can do and be confident I wont crash it. Otherwise it is a mess of fairly floss and I have to stop the lathe every pass and clear it.
I have not turned 4140 on this lathe so I can not comment specifically on it. Normally I prefer to use carbide on harder ferrous alloys, since it is much harder to burn the tip of the tool off. If I was to speculate, I would assume that 4140 could but better if you used a cobalt (M42 maybe) HSS. I machined some 316 stainless a while back and the advice I got was to use cobalt hss to get through the work hardening and prevent the edge being burned off. Once you grind up the tool its just a matter of playing around with a chip breaker and finding one that works at the necessary feed and DOC.
👍when you cut into do your cut angle then ...less to fine cut
These are informative videos for an aspiring machinist with almost no experience. Do you think it’s possible to use a dremel on a dremel drill press stand as a lathe, with a turning tool mounted to a mini compound table, to shave .2mm off of a pen refill barrel?
In a pinch, and if you can get everything properly fixtured I'm sure it would work if it is plastic or die cast metal. Ive seen people do similar stuff with a drill press. Cheers
Thanks for sharing, are screw tap and dies also the same HSS steel or they are more like M2?
They vary, some are carbon steel but more expensive ones are HSS
COuld you tell us wich stone is required for sharp the tool I am from Central America and terms are quite difficult to translate properly
روووووووعاتك
Excellent 🍬 😅💋
Where to get those blanks at that price?
Lol, short life or just a lot of material. Considering the price of steel is, in general, going up, it is a good deal. Nonetheless, your hobby/work or whatever you call it, I imagine that keeping an eye on steel prices would be beneficial.
Could you clamp on a piece of mild steel to the top of the tool to function as a chip breaker instead of trying to grind a chip breaker in?
I have never seen it done so I could not tell you.
@Artisan Makes where I can buy this HSS metal to make lathe tools?
This was a local deal, though you can find it for comparable prices on AliExpress
Is it possible at all to grind a HSS tool that will give a mirror finish on steel like carbide inserts can? None of the HSS tools I ground will ever do that. Perhaps it will do that with brass (but anything will give a great finish on brass), but for steel it always looks dull. Only time I've been able to get a mirror finish on steel is using carbide insert at their recommended speeds (which tends to be really high) at their recommended depth of cut.
If you are getting good results with carbide and you are happy with it, keep doing what you are doing. But if you really want to try with hss, getting a perfect cutting edge is essential. I usually lap the cutting edge and nose radius and that improves the finish.
Can you please type what you said around 7:08 ....to get a good surface finish , I need to take a _____________something or other. What a great video....Thanks
Corner radius, round off the corner
I have a good 2x72 belt grinder but a very average little bench grinder. Is there any reason not to grind tools on the belt grinder?
I don't see any reason why not. I have seen it done without issue. I simply don't because I don't have space for a belt sander. Cheers.
Chip breakers are always best on top side
Usually, but I've found it much easier to push the chip under the tool for aluminium.
Do these blanks not require heat treatment after the tool has been ground? I thought they come annealed and you have to harden them yourself?
They come pre hardened and as long as you keep the blank relatively cool as you grind it you won’t change the temper. Hss is pretty resistant to losing its temper .
@@artisanmakes thanks for the reply
My question is how are you supposed to set the tool rest angle when your reference surface is a round wheel.
No need to overthink it. Just scribe a line on the hss tool with the angle you want to grind and tilt the rest so that you can roughly cut that angle. There is a lot of leeway in grinding hss by hand so it shouldn't matter too much as to whether you get the angle spot on.
@@artisanmakes yeah I figured as much in the end.
I ended up following your video and ground something that actually cut, which was a big achievement for me. Now I just have to study up on speeds so I can accomplish a decent surface finish.
Can you kindly share the stone that you use? Thanks!
Its about 15 years old and I can not remember the name. Any diamond lap stone will be quite similar to this
Great video! I did the same thing, but in Portuguese! I would be very happy if you watched it! Thanks!
How can I ensure the bed on my bench grinder to 10 degrees?
I usually use a protractor but your phone should have an inbuilt protractor in it. The angle doesn’t need to be perfect, just close enough. Cheers
Why do you quench HSS? All I read advised not to as it buggers up the internal structure. As a wood turner we are forever sharpening HSS. White wheel and diamond card to touch up between sharpenings.
I dunk it water just to keep it cool so I can hold on to it. HSS different to normal carbon steel so the temperature you would generally reach when grinding it is unlikely to effect the temper or microstructure in any meaningful way
10 deg on the cutting edge.
Actually stringing is caused by incorrect feeds and speeds. Every metal has different feeds and speeds. I turn aluminum no problem at 650rpm on a mini lathe. High carbon steel 250rpm, mild steel 325rpm. The machinists handbook is your best friend. My speeds are modified due to using a mini lathe, but the book is the best baseline.
I can get 4 10x10x200 hss blanks for £19 in UK
I hate using mild steel practice tools
OMG. He is using grinder not a hand saw! finally!!!
yeah I was waiting for him to polish off a couple of bimetal blades trying to hacksaw the HSS ! :)
I know...I really thought he was gonna use the ole trusty hacksaw...LOL
Rest assured, normal stock cutting will resume next week. Cheers :)
😂
What? A hacksaw won't chip a HSS tool hehe so we use abrasive stones fro grinding it..
Yo
Shop eBay for a similar or even better deal on used and new M2 steel.
do not use a bench grinder, use a 5 inch angle grinder on the flat of the disc
Why not
hi. why not make your self a Dimond grinding wheel 1/3hp 1000rpm so easy and a quick touch an all is sharp again
I've actually jerry rigged something similar in the past from one of those $20 drill bit sharpeners.
A LEGIT MACHINIST CAN PROVIDE A SMOOTH FACE OF A CUTTING TOOL INSTEAD OF USING POLISHER. HAHA
Do what every works I guess
Throw the book away it's all theoretical find and learn by practice no need to hone or lap. If you in factory on piece work you wouldn't earn a penny. Sometimes negative top rakes work better than positive ones metals vary that much from one smelter to the next that the best way is to start with all rakes between five and ten degrees and most of your cutting will be trial and error. The curl on the swarf can cause a lot of damage to a work finish if it folds back on itself so try different top rake angles to encourage the swarf to come away with no inward curl.Practice makes perfect. Throw the book away.
Before Trump started the trade war 4 ears ago, I spend 9 us dollars to buy three 10x10x200 mm hs blank steel from China including free shipping to the USA. Now they ask 6 us dollars and traffic for ONE 10x10x200 mm hs blank steel.
Another case of TDS