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Parting tool angle

Larry Parker said:
What included angle do you have or find best on your parting tools?
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I find the angle pretty much the same way I do with a lot of tools- let the bevel rub, then lift the handle until it starts cutting.
But I wouldn't worry too much about the cutting angle with a parting tool. Running it straight in works OK, too. You're going to tear the fibers pretty much however you try.
 
I just regrind an old tool. It had a really blunt angle.of probably 110 degrees. I reground it to 60 degrees and it made.a huge difference in how easily it cut. I will ha e.to.measire my Thompson parting tool.but its probably close to that. I use them mostly as bevel rubbing tools so I can get by with sharper edges. I only scrape when sneaking up on perfect fit lids on boxed.
 
Is it just me, or do others also find that parting tools want to have a blunt angle. Over time, despite my best efforts, they migrate themselves to too blunt and I have to regrind them. Mysterious.

So, to address the OP's question, it depends on how long it's been since I took notice and restored the proper angle, which is about 60 degrees, as John says.
 
Dean Center said:
Is it just me, or do others also find that parting tools want to have a blunt angle. Over time, despite my best efforts, they migrate themselves to too blunt and I have to regrind them. Mysterious.

So, to address the OP's question, it depends on how long it's been since I took notice and restored the proper angle, which is about 60 degrees, as John says.
Click to expand...

it is consoling to know that there are other victims out there. I thought it was only me!
 
Dean Center said:
Is it just me, or do others also find that parting tools want to have a blunt angle.
Click to expand...

I think that is fairly common what we end up doing is putting micro bevel on the parting tool.
The grinder works mostly on the tip and sort of pushes the heel away.
When we keep resetting the platform to the last bevel or use the edge of the platform the
Bevel angle gradually gets steeper.

What I do is every once in a while is push the heel into wheel a little and let the tool go up the wheel slightly and then come down to the platform as it grinds the heel away.
 
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What I do is touch the heel of the bevel and then lift the tool until I see that thin gray streak across the tip ( I have CBN wheels so no sparks) flip it and do the same to the other side. At least on my Diamond parting tool. On My Thompson I can often get away with just one side. Unless done very carefully you gradually make the edge less acute.
 
Have any of you tried the narrow carbide insert parting tool in the full page ad in the latest AAW journal? High positive shear on the insert for easy cutting.

My guess is the narrow cutting width along with the small amount of material removed pretty much eliminates the usual tendency of hand held high shear tools to catch.

Here's a video. This is the same concept that led to improvements in metal lathe insert parting tools. Scroll down to find the video.

https://toolguyd.com/woodpeckers-ultra-shear-parting-tool/
 
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Thanks to all! I think maybe I blunted my tip as mentioned above. I need to take a look at that, wasn’t cutting very well.
 
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