OSG Exo-tap SF help

[jeff]

Can anyone tell me the right SF for an OSG Exo-tap

#4-40 spiral flute bottoming,the material is 304SS.

drilling .700 deep tapping .400 deep.

 

Thanks.

[b_daddy]

Jeff,

 

The book says 30-60fpm.

Good luck on tapping that deep with a #4 tap.

 

 

HTH

[jeff]

Thanks b_daddy,

I was initially running it way too slow I guess,only getting no more than 10 parts per tap.

25 more to go.

Jeff teh crossing fingers

[john_070]

use a emuge pusher style tap and go max on minor dia. i've tried them spiral taps that pull chips up with no luck on any thing remotely deep.

[chris m]

roll it roll it roll it

 

Chris teh cut taps suck in blind holes

[jeff]

I've never,ever had luck with roll form taps.

I know alot of people in here use them but they always bust on me.

What's the trick?

[chris m]

I roll threads in everything that I possibly can, from dogsh!t soft CRS and aluminum to 36Rc 17-4PH. I use OSG Hy-Pro NRT taps for the most part, though I run ExoTap NRT in the hard stuff. The real keys in my mind are having the proper prep hole size and running enough RPM; a lot of people run too slow and that can really kill your tap life.

 

C

[Guest CNC Apps Guy 1]

In my experience, most people tap WAY too slow. If the material is hard then run at the middle bottom of the Reccommended SFM range, if it's softer, run more towards the top of the range.

HTH