Chatter in groove cutting

phelop said:
Yes, is a practice part, the tool that I have is actually a micro 100. (.125 groove ), I will follow you'r advice and look for different stanless steel.

Thanks
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If that is a Micro 100 carbide tool then it is possible to save it; I've done it with hand held diamond stones before I got my Accu-Finish machine. If you want to try it, start with squaring up the nose and clean up all the edges and then flatten the top. Take a close look at the relief angle under the edge. It may be just the camera angle but there appears to be very little relief there. If there is at least 5 degrees then it is probably adequate.

If I were going to groove that work piece, here is what I would do:
  • I would make sure my tool is freshly honed and sharp, with sharp corners and adequate relief under the cutting edge.
  • Orient the tool so the top surface of the tool is horizontal, then set the tool height about 0.005" above the lathe centerline to accomodate tangential cutting forces.
  • Locate the tip of the tool in the location of the groove and bring the tip of the tool into contact with the work, then zero the dial on your hand wheel. Rotate the work by hand and gently and slowly feed the tool into the work until it starts to cut freely. You are trying to break or cut through any work hardened surface before turning on power. Once the tool cuts freely you can turn on power.
  • Set your speed so that it allows you to feel a slight resistance to the feed as you cut the groove. The speed should be slow enough to allow you to feed comfortably, without having to frantically turn the hand wheel to keep up with the cut. You have to keep the tool cutting continuously; do not dwell.
  • Be sure to use a lubricant/cutting oil. I prefer sulfur-bearing cutting oil for SS.
  • If the tool chatters or stops cutting at any point, stop the lathe, turn the work by hand until the tool starts to cut freely again and then turn on power again. Focus on feeding so the tool cuts continuously until you reach final depth.
The above process works. I've cut thread relief and O-ring grooves in SS many times over the years and this works for me. You might give it a try.
 
I keep a couple of HSS tools with cobalt for that sort of work, they usually do pretty well on stainless. If you are not grinding your own tools you should look into getting a small bench grinder- it's great being free from buying ready made tools and you can make all sorts of cool custom cutters
 
markba633csi said:
I keep a couple of HSS tools with cobalt for that sort of work, they usually do pretty well on stainless. If you are not grinding your own tools you should look into getting a small bench grinder- it's great being free from buying ready made tools and you can make all sorts of cool custom cutters
Click to expand...

I will check how to grind my own tools.
 
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