Milling copper.

[rwm]

So how about tapping copper? Any special considerations? I need to do 6, M3 holes about .250 deep

 

[ChazzC]

So how about tapping copper? Any special considerations? I need to do 6, M3 holes about .250 deep

I used something on brass a while back, but can't remember: all I know is that the label said it would work. Remind me Friday – I should have access to my cutting fuid collection by then.


Charlie

 

[rwm]

I think I'm gonna make copper rivets and use those instead of screws. That will be easy and super secure.

Edit: tapped a test piece of copper bus bar M3. It was pretty easy. I still may go that route.

 

[pdentrem]

I never tried it on copper. Can try soya oil. It works surprisingly well and has a very high smoke point. It will go bad over time.

 

[machinistnoob]

So, I got it. A .5X.5 slot taking .03 per pass, widened to a .625. Used a brand new .5 two flute hss endmill and plenty of anchor lube. Went well and turned out clean and sharp but I attribute that to my mill. Wouldn't want to do this on a bench mill.
...gotta drill some deep holes next

 

[ChazzC]

So how about tapping copper? Any special considerations? I need to do 6, M3 holes about .250 deep

I used something on brass a while back, but can't remember: all I know is that the label said it would work. Remind me Friday – I should have access to my cutting fuid collection by then.


Charlie

Robert: I managed to move enaough stuff to be able to grab my bottle of Rapid Tap:


It also comes in 16oz and 1 gallon bottles (and paste), but I just wanted to try it out (and 4 ounces will last me a long time). Although the description on most of the sites that sell it don't mention it (even Relton expects you to read the label), the label says "Copper;" I tried it on brass and it worked well.