Teng Drilling

[bug_hunter]

Hey Guys,

I have three end mills similar to that which is shown below. The taper is a B&S #9 to be used horizontally in my Burke No. 4. I am looking to drill and tap the teng for a 1/4-20 draw bar to ensure I do not create a projectile. The teng is hardened as such I have a carbide bit specifically for this purpose. I have a drill press, and I have a SB 9c. How can I safely and securely hold the end mills for drilling and tapping?

Thanks a lot for the insight,

Greg

 

[benmychree]

If B&S tapers are whacked home with a soft hammer wielded in a forceful manner, it is not so likely that they will come loose under cutting forces, especially if you do not push them too hard; I would not worry about a drawbar on a tanged tool, yes, it is spelled TANG.

 

[markba633csi]

Forget about drilling and tapping- an impossible job.
Either buy different cutters that take a drawbar or use a BS9 collet and straight shank tooling

 

[Alcap]

If you must have the end thread , cut the tang off and weld a nut in place . Youll need to make a custom draw bar , maybe just threaded rod , but I believe you were planning that anyway . Ive done similar for a boring head and ER32 collet to fit the MT2 with 3/8“-16 draw bar in my Clausing 8520 one had metric threads the other was 3/8”-16 but my self releasing drawbar would only thread in a few threads .

 

[bug_hunter]

I made a split collar (fastened together with two 1/4-20 cap screws) with the annular at a B&S #9 taper with the smaller diameter the same diameter as the recess on the TANG end of the cutter. I was then able to hold the entire assembly in my drill press vise and allow the cutter portion of the assembly to protrude through the drill press table. No slippage.



Thanks to everyone for the insight.

Greg

 

[Alcap]

Were you able to drill and tap easily?

 

[bug_hunter]

Drill, yes with a carbide bit. Tap, not so much. Broke a tap quite quickly, cut that portion off, softened the tang with some heat, then tapped relatively easily. Nice, clean thread.