Speed & Feed?

I guess I go by eye when it comes to RPM/diameter. If the chip turns brown before it leaves the tool, I'm going too fast. slow it down a little. Any speed below this is good. In the hobby shop there's no premium on how many peices you can make per hour. That's all suggested speeds are for. Steel will cut well at 10% of it's rated cutting speed.
 
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Thanks guys,I’m using HSS cause was told get better finish when taking off very little such as.002.Right now shaft is at little over 1/2 but finish OD will be .005 So wanting to make few passes different feed using HSS which first time to grind one.If I figure this correctly rpms should be 900 looking at few charts.I did try .003,.005 then .0025 It does look better,I did take a pic of the HSS tool that I grind but it was not a good pic,I know its hard look at the pic of the shaft be able to tell me what I need to do but please do.With cutting oil,I did add a radius nose which did not have maybe 1/32SHAFT 6.jpg
RPM-900
Feed is .0025
 
Some guys use more HSS than Carbides and some more Carbides than HSS. Sometimes economics come into play. Hss is good to know how to grind. Sometimes you need to make a tool for yourself for the project. Fine finishes can be had on both wih proper parameters of tool geometry, speeds and feeds for the machine. Best to learn what your chips are telling you.
No need to run the crap out of your machine for Aluminum!
 
Kroll, can we see a pic of your tool? Try to take a clear one so we can see the tool angles and nose radius.
 
Guess reading all post again picking up little more info.Here few pics of the cutting tool but before you laugh this is a first for me using and grinding HSS.I tried the inserts but not getting a good finish removing .002 or so went to the HSS.The radii is not as big as what the pics looks like.tool1.jpgtool1.jpgtool2.jpgtool3.jpgtool4.jpg
 
Thanks, Kroll, that helps.

First, let me tell you that tool grinding is difficult to do at first. If this is your first tool then you did WAAY better than I did with my first one, trust me.

Okay, what I see is that you have several problem areas to correct:
  • You have almost no side relief. In the last pic above, look at the cutting side of the tool. See how it runs almost vertically? There is little to no clearance under the side cutting edge so the tool will plow instead of cutting. This is the biggest issue but easy to fix; just angle your tool rest and grind away the material right under the cutting edge.
  • Your side rake looks good but you need more back rake. In picture #3, see how the top of the tool is almost flat from the tip running back to the shank of the tool? That angle should run downward more.
  • The nose radius is big, too big.
My suggestion is to work on the side relief angle. That alone will allow the tool to cut much better for you. Just fix that first and see what happens. I will bet the cut improves significantly.
 
Thanks Mikey,going to give that a try shortly and work on making the radii smaller.I have no ideal on how to load this short file clip,I ask my daughter when she gets home.
 
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