Mirror finish with HSS tool bits

[OTmachine]

Us machinists, at N.A.R.F., always had profilometers available to use. Aircraft rework was pretty particular. Q.A. was always there for first article and spot inspections.

 

[Janderso]

Last time I looked into a mirror finish , I hated what I saw . If you need a finish gage , they go by rms these days

I don’t know David, you seem pretty sexy to me.

 

[benmychree]

My friend Alex(Apple engineer) will only use a laser,checking the finish on phones.

In my day there were no phones to check finish on ---

 

[taiwanluthiers]

So I guess the last 5 or so post don't answer anything.

Basically we can expect a smooth finish but not shiny in any way right?

 

[benmychree]

So I guess the last 5 or so post don't answer anything.

Basically we can expect a smooth finish but not shiny in any way right?

Fair enough! What would life be without a bit of humor?

 

[Ken226]

The best I can do with a freshly sharpened and honed HSS tool. Definitely not a mirror finish.



But, it's 12L14 steel, so it's kinda cheating.

 

[taiwanluthiers]

The best I can do with a freshly sharpened and honed HSS tool.



But, it's 12L14 steel, so it's kinda cheating.

I can't get leaded steel. All I can get is annealed 4140 or low carbon steel, and various tool steels. However since 4140 and low carbon steel cost the same where I am at, I just get 4140.

 

[benmychree]

The best I can do with a freshly sharpened and honed HSS tool. Definitely not a mirror finish.



But, it's 12L14 steel, so it's kinda cheating.

Yes, kinda!

 

[timmeh]

Low speed(20-30rpm), very fine feed(.001"), flood coolant, .020-.040" doc.
HSS tool shaped a bit like a roughing tool,
Finishing tool with enough 20-25 degree chamfer on leading edge to account for the doc.
Done on free machining mild steel, may require some trial and error on other materials.

 

[taiwanluthiers]

So what's wrong with very high speed on HSS but very light cuts? I mean HSS doesn't really burn up that easily anyways. We're not talking about high carbon steel here.