Drilling PCB?

[tech_101]

Hi all,

Where's a good place to buy drill bits for drilling PCBs?  Also, any recomendations on the best type of drill for a beginner to buy?  I'm located in Calgary, Alberta, Canada, if you have any suggestions for places that are local to me, that would be wonderful.

Thanks,
Justin

 

[gogo2520]

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=34640
Check this out
                                Hope it helps
                                gogo

 

[MP1]

A dremel is great since it runs at high speed in the 30,000 rpm range. This will give your bits additional life. It will also give you a nice clean hole. Slower drills will actually burn the pc board material and give you a discolored hole. Some type of fixture such as a drill press will keep you from breaking bits from side movement. Also, for drilling pc boards, do yourself a favor and do not buy the cheap harborfreight bits. Buy carbide bits from a reputable hardware source. They are more expensive, but they will last longer and give you much cleaner holes. As bits begin to dull, they will start to distort the hole in the copper. Some places sell re-sharpened bits. However, one thing that causes a short life in the small carbide bits is impact. If you purchase used bits, you do not know how much they have been abused or how long they will last due to abuse. You should have a distributor nearby that deals in carbide cutting tools such as saw blades and bits. This is the best place to purchase your bits; even if they have to order them.

Good luck!

MP

 

[tech_101]

So if I pick up a dremel and something like http://tinyurl.com/dzfsf ?  I'll have to check some local hobby stores to see if they have the right size bits.  Should I be looking for the 0.5 to 1mm range, as rigdoctor99 mentioned?

Justin

 

[MP1]

That is correct. You can check your pc board layout to see what sizes you actually need and narrow down the need for many sizes. For example, sizes which are close can be edited and you might only need 2 or 3 different sizes.  Maybe less.

You might also want to employ a magnifier with a light on your drill fixture....oh, maybe that is just for us older guys...If I am controlling the drill bit, I like to see it up close.  ;D

MP

 

[tech_101]

Thanks for your help everyone.  I've called my local carbide tools dealer, he's checking pricing with the manufacturer for me.  I'm getting a couple #70 and #67 bits, and one #65 and #63, hopefully they'll last me a while.  Then I'll be picking up a dremel and drill press stand for it from home depot..  Hopefully I'll be able to finish the PIC programmer project that's been waiting to be drilled out for a year now.

Justin

 

[oldgrandpainmi]

Tech_101,

Depending on the number of holes to drill, I've used High Speed Steel bits for years.  Carbide may last longer, but can cost 400-600% more than HSS.  I get my numbered bits at a local "You-Do-It" center for a buck or so each. (up to #70)

Since you are drilling thru fiberglass with copper plate, you don't really need the full speed of a Dremmel.  I use a variable speed Dremmel at 1/3-1/2 speed.  Even with fiberglass, speed causes heat, which dulls the bit faster.  The key is, like all types of drill bits in a press, is to prevent the bit from wandering and bending.  I have actually broken the bits in half to minimumize their length to about 1/4" from the chuck.  This cuts down on wandering and flexing the bits as you drop down on bit diameter, and cuts a cleaner hole.

Food for thought.

oldgrandpainmi

 

[MP1]

My 2 cents:
One thing I like about the carbide bits better than the high speed steel is that they will usually break before they ever dull. With high speed steel, I noticed the bits would dull fast. Even more so if you use paper phenolic boards. This would end up leaving me some holes with black burned marks before I was able to change the bit. Nothing worse than a ruined board because your bit burned through it and left a black mark. I have never had a problem with wander, but I use a CNC drill station. I have a PC board lab and run a large qty of boards through it. Thus it is certainly more worth while for me to stock the carbide.
It is interesting that you slow down your dremel. All professional PC board drilling machines run at around 30,000 rpm. What speed is 1/2 to 1/3 on your tool?

MP

 

[oldgrandpainmi]

MP,

I honestly don't remember my Dremmel speed rating.  I have it put away right now.  (Had back surgery last year and haven't dug alot of my stuff out yet.)

As far as your statement about carbide -vs- HSS, yep!  If you are ANYTHING more than a hobbiest, carbide is the way to go.  I'll even say if you are a hobbiest with A LOT of drilling to do, that go carbide.  But if you only have small PCB's with limited number of holes, then HSS is my choice.  If you break one, then you are only out a buck or so.  Besides, as I stated, with HSS, I break them anyway to achive the 1/4" lengths.  Even with numbered carbide bits in a dremmel with a press, bits break.

As a hobbiest, I can justify $5 for 4 bits to do 1-2 small PCB's.  I can't justify $20-$30 for the same bits, especially if the only way to get them is mail-order, to do such a low run of PCB's.  If I could justify spending that much $$ for things I may only use once or twice a year, I'd buy my stuff off of the shelf and bypass the construction steps, or, have them etched and drilled for me.

It is a personal decision based on $$ available.  That is why I drive a Chevy Pick-up and not the Lamborgini I have always wanted!!!

oldgrandpainmi

 

[MP1]

I certainly have to agree on that point. For a one time board project, the cost of bits for 5 or 6 different hole sizes would not justify the cost to make 1 pc board. One could have a board house produce the board at nearly the same cost.

(Hey, nothing wrong with a Chevy truck. Have a Silverado, myself.)

MP