Drill bit recommendations for ebony?

[amowry]

Any recommendations for bits for drilling bridge holes? I use 3/32" holes and I've always used twist bits, but they sometimes seem to wander a little. I was going to order some 3/32" brad points, but my experience with those and ebony has been that if the spurs are too long they require too much force to use and that causes them to overheat. What do you guys who make bridges all day use?

Thanks!

[Paul Hostetter]

Slow speed, brad points, no problems.

[mandroid]

.. with some materials it's good to clear the chips out of the twist of the drillbit, a few times to make the cutting go better..

[Darryl Wolfe]

Slow speed, brad points, no problems.
yep..and I usually avoid trying to go thru in one firm pass. Back er out a few times and you will avoid the occassional crack from getting too firm and hot with it

[sunburst]

I don't make many bridges, but I've split a few pieces of ebony trying.
Yep, go slow and lift the bit several times to clear the chips. I clamp the ebony securely in a drill press vise to avoid splitting (and assure that the holes go straight through) and just use a standard twist drill because I don't have a brad point that small.

[amowry]

Okey-doke. Thanks folks. I'll give the brad points a shot.

[bryce]

Do you use a drill press and a vise (I use a mill but same result)? I use a letter drill (don't recall the size) a bit smaller than I want, then use a reamer to size the hole I want on the saddle. I don't go very far each plunge an I have an air hose blowing on it to help bit stay cool. On the base I had to try several different sizes to find one that would let me tap the 5-40 threads I want. Same thing. I only turn half turns before backing tap slightly to clear while using the air also. Takes a while but the 5-40 stud has no slop and doesn't want so turn while adjusting thumb screw. Oh yea, the bits 118 degrees I think.# #David

[amowry]

Thanks David. I do use a drill press and vise, but I've always found that my twist bits flex and wander a little. Maybe it's the quality of the bit. I have some brad points on the way, so I'll let you know how those work.

I've found that 3/32" works fine for tapping the 5-40 threads.