HSS or Carbide inserts fot lathe turning????

Went bad... I'm in quite of bit of pain which is playing with my patients. However, after going through my bits I found a piece of known m2 HSS and started grinding on that. It was quite a bit harder to grind than the other bits I have which leads me to believe that they aren't HSS. Thanks for all the responses and I'll get back to you guys later.
 
yes please take care with the foot. Let us know how the known hss works start with very light cuts .005 or so. I'm still not sure it is all in the bits.
 
I have found that a properly shaped and sharpened HSS bit will keep up with a carbide bit and even provide a smoother finish on your material. The key to getting the HSS to work so well is the way you grind the tool in the beginning. Make sure their is relief below the edge to allow just the tip to make contact with the work. If the relief is inadequate it will drag the face of the tool on the material and result in the bit tearing off little bits instead of slicing off a chip. The top of the bit also needs a little bit of relief to help lift the chip and eject it from the cut. Some fellows will also make a notch that the chip will push into and break so they don't get the long stringy slivers all wrapped in the machine and tool. The sides of the tool should also have a slight amout of relief so that if you are cutting up to a shoulder or an edge the bit will not drag on the material either. The angles on the sides of the bit are not really important as long as they are actually there. The top, and front are the two most important angles and once you have formed the tool to your needs you should use a diamond hone to dress those edges so that the are nice and sharp. You should also remember to hit the tool an occasional few licks with the hone so that it doesn't get extremely dull before you stop to sharpen it again. If you keep the hone handy you can hit it a few licks without taking it out of the holder and go right back to work. Interupted cuts such as turning a square block into a round rod is very hard on tooling and is extremely hard on carbide since it is as brittle as glass and will chip and break at the slightest hint of an interrupted cut. Tubal Cain (MrPete222) on you Tube has some wooden demo bits he sells that will help you understand the different angles used and how to grind them into your blanks effectively the first time. Good luck and don't give up, sometimes it just takes a while to get the hang of it and once you do it will become rather easy to do,

Bob
 
markknx.... Thanks bud... I'll probably take you up on that. My wife is all over me right now for not staying off my foot. So I'll be doing that for a good part of the week. I'll order some HSS bits from ENCO today. Depends on their shipping, but I heard they're pretty quick.
 
Please do! In the mean time pay attention to your reliefs, These are very important. Go back and look at the drawing posted by one of the members. See what is labbled as reliefs. could be just the pics but you seem to be missing the reliefs. Also be sure to dip the bit in water often and long enough to cool them. If you see blueing on the bit it is getting to hot and will lose it's temper.

Mark
 
Well.... I went back to basics.. Somewhat, I took off the QCTP and went back to the original tool holders that come with these lathes. Drove to MSC and picked up a half dozen 3/16" HSS tool bits and a couple of 3/8" pricey made in the U.S.A. bits. Watched some videos re-read all the posts you guys responded to and had my nose in the Craftsman/Atlas "machine tool operation and machinists charts" book right next to my belt sander and grinder. Had a protractor out. I'm happy to say that I made a right hand, left hand and a round nose tool bit with success. I was surprised at the finish I got out of the round nose tool bit.. All of them made nice curly strings of cut metal. I'm going to stick with the 3/16" tool bits for now, due to the price and am saving the 3/8" when I'm really ready and have more experience in tool grinding. The 3/16" seems to be easy to recover from almost making a mistake than a larger bit.. Thank you to all you guys. You're great. I'll be asking more questions so bare with me. I wish all the forums were this patient.
 
Glad to hear you got it. Not rocket science, just need to hold your mouth the right way and get the planets to align.
There'll be no stopping you now.

Greg
 
It's really nice when you have that "AH-HA" moment, thinking "so that's how you do it". This is definitely one of those hobbies where sometimes you can have instant gratification. That said, its also one where you might have to put in hours and hours... and more hours, till you get there. But as someone mentioned on this forum (and I can't remember who at the moment) once said "Break it down to little steps, do each step in turn, and you'll eventually get it done. Examined individually, each step is fairly simple and/or straightforward, while the whole seems overwhelming. You've just taken one of your first steps by proving that you can make your own forming tools. Add to that, you did it yourself. Certainly, the advice and knowledge here proved invaluable, but no one here was holding your hand while you were grinding that tool. At least, that's how I felt when I first got it right. So have a cold one and relax that foot. :)

Terry
 
Congratulations, Pipehack. Nothing succeeds like success.
 
I'm just glad you stuck through it! It can seem so frustrating, and then you get another lesson under your belt. Good for you man! We have all had this help when we started, so always feel free to ask.


Bernie
 
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