Drilling brass

[marcros]

I have some brass round bar to drill into (centrally into the "end grain"). The holes will be 2mm x 30mm deep in one piece, and 10mm x 30mm deep in another.

The tools I have is a wood lathe, speed from 300 to 2000rpm. or a hand cranked pillar drill.

Any tips on drilling brass? high or low speed and feed rate? I have new hss jobber drills but have been warned that brass can be "grabby".

 

[Myfordman]

The 2x30 will be challenging. Use a slocombe drill to start the hole. Stone the cutting edges of the jobber drills to have a negative rake and keep them for brass in future. Stub drills could be useful to do the larger hole and most of the 2mm hole although are unlikely to be long enough to complete the full depth. The wood lathe is not the ideal tool but adjust everything for maximum rigidity or find a friend with an engineering lathe.

 

[marcros]

slocombe drill is a new term for me, but having googled, I have one of those. I have a collet chuck, so I can hold the whole bar in that and give it a try. I can lock down the tail stock and extend the quill. fast or slow rpm?

Does brass work harden?

 

[MusicMan]

It doesn't work harden much and needs little lubrication (yes it does depend a bit on what type of brass it is, but rod should cut freely). Yes, start with a centre drill (Slocombe). The 10 mm should cut easily with a medium speed. If problematic then drill 5 mm first. For the 2 mm drill the danger is drill breakage. For this one, use the highest speed and take it slowly. I agree it is pushing a wood lathe a bit (2mm x 30 is not easy on an engineering lathe) but you can give it a try.

 

[Sawdust=manglitter]

I used a wood lathe for drilling and knurling a round brass bar and it worked great...

the-keeper-router-plane-wip-t109785-30.html

Didnt drill a hole as small a diameter as 2mm though!

 

[Phil Pascoe]

The problem being, of course, is that when the 2 mm bit breaks off you won't be able to get it out or finish drilling the hole.

 

[MusicMan]

The problem being, of course, is that when the 2 mm bit breaks off you won't be able to get it out or finish drilling the hole.

True. But you could make it into a 10mm hole, with some excitement. So one should do this one first and use good drills!

 

[sunnybob]

I know its only brass and not iron, but I would use two or even three sized drills to make a 10 mm hole.
the 2 mm will definitely be challenging.

Feed VERY SLOWLY, turning the wheel with the lightest of finger tip pressure, and back out very often to allow the swarf to clear the drill because its quite common for the swarf to jam and thus snap the drill.