I got the 10-32nf 1" deep though holes done just fine. Ground a tap down with the lathe and a tool post grinder. However I am now trying to do 1/4-20 blind holes and breaking taps like crazy. 6061-t6 alum. #7 drill 0.8 deep, tap 0.6 deep, rigid tapping with a floating holder, spiral fluted tap, plug and mod. bottom style tried them both. 800 rpm , F40.
Last tap I just broke was a Hertel 3fl mod bott. TiCN coated ......broke after 7 holes.
Flood coolant aimed well at the tap.
I did successfully tap 8-32 blind holes .55 deep in another part of this job last week. Why can I not get a 1/4-20 to work???
Supermax Rebel1 VMC with Fanuc 0M-C
Thank You, Randy
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