PCB Drills

[aggie_67]

Just getting ready to drill my pcb boards but need to order drills. Problem is I can't find any reference as to what size drills to use. Know it probably depends on components being used but is there one basic size that is acceptable?

[joecnc2006]

I think people use 0.6mm or a 1/32" bit, but don't quote me as i have never made one.

Joe

[Carel]

Hole through chip, resistors and capacitors normally are drilled 0.7-0.8mm, TO220 housings like 5 volt regulators are 1.0mm. You can buy them in HSS or Carbide. HSS lasts approx. 600 holes. Make life easy and use a (mini) drill-press.

[joecnc2006]

oops meant to say 0.8mm 1/32"= 0.766mm

[roughrider]

goto welding suppler get torch tip cleaning drill bit .
littledrikk bitsto clean actaline torch or gas welders

[pminmo]

.032 #67, is a common usage size for resistors and capacitors, DIP packages,
larger resistors will take a .042 #58 same for TO-220. Diodes many take an .046 #56. Components are different, I start out with .032 because only a few components need drills smaller, and then usually the .032 isn't a problem for those. I'm really getting to like surface mount and saying the heck with drills!

[martinw]

Originally Posted by Carel Hole through chip, resistors and capacitors normally are drilled 0.7-0.8mm, TO220 housings like 5 volt regulators are 1.0mm. You can buy them in HSS or Carbide. HSS lasts approx. 600 holes. Make life easy and use a (mini) drill-press.

Dear Carel,

Excellent advice. Could I add a little?

0.8 and 1.0 mm holes cover most through hole components. If you have discrete wire screw-down PCB connectors, you may need 1.3mm as well.

0.6mm holes may work for most DIL chips, but I tend to avoid them. Too easy to break. Go for 0.8mm instead.

If you are mounting the board on pillars, 3mm holes might also be useful.

Those four bit sizes may not be all that you need, but they are a good start IMHO.

It really helps if you have put a small "hole" say 0.3mm diameter at the centre of the pad on the PCB artwork. This helps you centre the drill bit if you drill by hand, either "freehand" or in a small drill press. I've never had much luck "freehand", but plenty of people have.

If you have to increase the diameter of a hole that you have already drilled, be extra careful. That is when I always break small dia. bits.

One more thing.. it is vital that the size of the pad is large enough to leave a reasonable area of copper after the hole has been drilled. If you do not, when you try to solder the component lead, the copper pad may lift off as it gets too hot.

Best wishes

Martin

[fyffe555]

Originally Posted by aggie_67 Just getting ready to drill my pcb boards but need to order drills. Problem is I can't find any reference as to what size drills to use. Know it probably depends on components being used but is there one basic size that is acceptable?

Harborfreight has recycled carbide bits from the pcb industry. Work great;
http://www.harborfreight.com/cpi/cta...emnumber=44924

recommend using a drill press or cnc machine, freehand will break them..