Models for grinding HSS Lathe Tools

I would think a rounded edge might not give enough relief on the outside edge, but truly, I'm just a beginner at this. I defer to others with far more experience. The tool was good enough for what I needed to do. Could it be made better? Very likely. First time trepanning was unsettling, to say the least. Once the edges were sharp and had sufficient relief, had no troubles.
 
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I'm still getting a little chatter, but it's much improved. I didn't hone it much for this test, so I'll do that as well.

I went back and watched a video from Joe Pieczynski's channel and got a good tip that helped a fair bit, keep pressure on the handwheel. It chatters more with lighter pressure, keeping the tool tip buried in the work helped. I'm sure pulling it back into the holder helped as well.

The biggest change in the grind was to taper from the front cutting edge. I had intended that, but didn't get enough. I also ground a steeper angle on the outside.

Thanks for the suggestions!
 
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I'm still getting a little chatter, but it's much improved. I didn't hone it much for this test, so I'll do that as well.

I went back and watched a video from Joe Pieczynski's channel and got a good tip that helped a fair bit, keep pressure on the handwheel. It chatters more with lighter pressure, keeping the tool tip buried in the work helped. I'm sure pulling it back into the holder helped as well.

The biggest change in the grind was to taper from the front cutting edge. I had intended that, but didn't get enough. I also ground a steeper angle on the outside.

Thanks for the suggestions!
 
I have a question. I finally am able to start cutting on my 9A and im going to make a Generic tool for cutting and turning in one. Is that possible. Is it possible to make the tool without having to rotate the toolpost?
 
I have a question. I finally am able to start cutting on my 9A and im going to make a Generic tool for cutting and turning in one. Is that possible. Is it possible to make the tool without having to rotate the toolpost?

Are you using a QCTP or the older style lantern toolpost? The tools we make here are designed for the QCTP where you hold them mostly flat with the ways. The basic ideas will work, but the angles will have to be adapted.

Why hesitate to rotate the tool? I do it all the time.

Turning is cutting, so I'm missing something. :) I use the square tool most of my general turning. If you mean facing cuts, I use a square there too, just in a different holder so it hangs out the other end and put it on the other side of the post. The knife tool works pretty well there too.
 
QCTP but i like leaving the block square to the work so i would like to make a generic square facing/turning tool in one. But id also like to use it to turn up to a corner and face out.
 
QCTP but i like leaving the block square to the work so i would like to make a generic square facing/turning tool in one. But id also like to use it to turn up to a corner and face out.

You will want to try to mimic the angles on a carbide insert holder, having the cutting point to the left and forward by a few degrees to get clearance for both. Perhaps angle the bit in the holder a few degrees left so you can clear everything without grinding the whole length of the bit. It's easy enough to set the block straight when I want it that way, so I've never tried it myself, but I think it would work. I just use a faced off part or the tailstock quill to make it square. Quick and more than square enough for my needs. If you are setting it with a tenths indicator, that might take a bit longer. :)
 
So this is a stupid rough sketch i just did on my phone but would i have an my cutting trouble on my 9A if i made my square tool like the little sketch on the right? I know the square tool is generally made like on the left but i find it harder to turn up to a shoulder then. I am trying to make the tool so i do not have to rotate my qctp block and i can keep it nice and straight. If it will cause problems cutting then i will make it the normal way.
 

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I don't think so. I have cutters that I ground similar, it cuts fine.
and if you don't like it, well re-grind it.
 
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