Hey Guys,

I bought some PCB specialty drill bits about two weeks ago. I believe they range from 0.5mm to 3mm. Last week, I tried drilling holes in my first board with a Craftsman 3/8 drill. I drilled the first hole perfectly, but the bit broke on the second hole; I'm not entirely sure why it broke (maybe too much pressure? The bit started wobbling for a while), but I think I may need a smaller drill that can accommodate the tiny bits.

What kind of drill do you guys use for hole drilling?

 

Umm..senior moment. Can't remember the name of it so I took a photo.
Put this in a drill press so you don't aim at an angle and break the bits.

Oh yeah...pin vise.

 

These are aimed at HS spindle, ~12k - 20krpm.
A dremel might do it.
Max.

 

I use a dremel tool and a dremel drill press stand. I have only broken one bit, and that was because I hit with the board + backing board as I removed it.

Bob

 

Hey Guys,

I bought some PCB specialty drill bits about two weeks ago. I believe they range from 0.5mm to 3mm. Last week, I tried drilling holes in my first board with a Craftsman 3/8 drill. I drilled the first hole perfectly, but the bit broke on the second hole; I'm not entirely sure why it broke (maybe too much pressure? The bit started wobbling for a while), but I think I may need a smaller drill that can accommodate the tiny bits.

What kind of drill do you guys use for hole drilling?

You're going to have a very hard time controlling the 3/8" drill unless it's installed on a bench... but Max is right, you need around 10,000 RPMs for those bits to behave properly (think tangential speed of cut at the drill's outer diameter)... a Dremel is definitely in order for this application... also, I hope your bits are carbide and not hss...

 

I guess it didn't help that I drilled the holes manually (with no drill press). I probably went at it with an angle.

 

I guess it didn't help that I drilled the holes manually (with no drill press). I probably went at it with an angle.

THAT explains a lot... don't sweat it man... buy a Dremel... I normally drill those holes manually without a hitch using the flex shaft...

 

These are aimed at HS spindle, ~12k - 20krpm.
A dremel might do it.
Max.

I have an advantage: A 1938 Walker-Turner drill press that I redesigned. Cast iron like, you don't try to move it, you bolt it to a bench, and the bearings were all changed to 21st century with adapters I designed and installed.

 

I have an advantage: A 1938 Walker-Turner drill press that I redesigned. Cast iron like, you don't try to move it, you bolt it to a bench, and the bearings were all changed to 21st century with adapters I designed and installed.

Show-off ...

 

Do I need some sort of special chuck for the tiny bits I have? To be honest, I've never used a dremel before.

 

Do I need some sort of special chuck for the tiny bits I have? To be honest, I've never used a dremel before.

The dremel already comes with a miniature chuck that can hold bits from 1/64" up to 1/8" in diameter... Also, I believe Craftsman and other brands have Dremel-clones in their catalog that are quite acceptable too...

 

Do I need some sort of special chuck for the tiny bits I have? To be honest, I've never used a dremel before.

Dremel use a collet type chuck. You can buy various sized collets for most dremels (1/8, 3/32 and 1/16 are the options - If I remember correctly). Check the diameter of your bits and make sure what ever dremel kit you buy has the right collet. Otherwise they are an additional $5 for each collet

 

I drilled about 50 holes (0.8mm) just yesterday with a 6 foot tall drill press weighing about 250lb with a 1/2" chuck. No problems whatsoever.

You can pick up a small drill press from Harbor Freight for half what a Dremel costs. Would work much better than any handheld solution.

 

I drilled about 50 holes (0.8mm) just yesterday with a 6 foot tall drill press weighing about 250lb with a 1/2" chuck. No problems whatsoever.

Bet you also go hunting for rabbits using a bazooka...

 

I found this dremel on Ebay for what I think is a good price. (http://www.ebay.com/itm/Variable-Sp...1391497307?pt=Power_Tools&hash=item41843d805b)

I would need to buy the right chucks, though.

 

I just added a HS spindle to my knee mill in order to use the HS bits, these use a small collet known as ER11 but the dremel or similar will work but use a rigid stand of some kind.
http://www.maritool.com/ER-Collets
Max.

 

I drilled about 50 holes (0.8mm) just yesterday with a 6 foot tall drill press weighing about 250lb with a 1/2" chuck. No problems whatsoever.

Same here. My 1/2" drill press chuck will go down so far, I can't remember without going to the shed and hoping I can find the box and read the label. What matters is that you can't see any wobble in a 0.031 inch drill bit...without using a pin vise!

 

I just added a HS spindle to my knee mill in order to use the HS bits, these use a small collet known as ER11 but the dremel or similar will work but use a rigid stand of some kind.
http://www.maritool.com/ER-Collets
Max.

That looks like pretty high quality tooling there, Max...

 

I'm on Ebay and most of the collets that I need ship from Hong Kong, Thailand, or somewhere else in the East; maybe I'm not searching for the right thing here. I'm searching "0.5 mm dremel collet".

 

That looks like pretty high quality tooling there, Max...

I picked up the HS spindle and a HS DC motor fairly reasonable off ebay, so I just needed a couple of extra collets.
Max.