madbeanpedals::forum

General => Open Discussion => Topic started by: Haberdasher on July 19, 2010, 08:28:13 PM

Title: Ideal Drill Bit Size/Range for PCBs?
Post by: Haberdasher on July 19, 2010, 08:28:13 PM
I have some wire gauge carbide bits here and a press.  I don't really have a scrap piece to drill test-holes in.  I was hoping to avoid messing up any of my good material in searching for the right bit size.
I have read that #68 is used for resistors and caps by a lot of folks, but I don't have that size as it turns out.

What is an acceptable size for this?
And do I need to use a bigger bit for any other components like diodes or ic's?
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: madbean on July 19, 2010, 09:24:51 PM
#65 is perfect for all regular components. Not too large or small. #68 is too small for some diodes.

For PCB mounted pots, use #60.
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: Haberdasher on July 19, 2010, 09:37:42 PM
Looks like I have a couple of #63's.  You think I'll be able to work with this?
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: jkokura on July 19, 2010, 10:19:45 PM
yes.

Jacob
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: Haberdasher on July 20, 2010, 05:58:44 PM
First attempt.  :-\

My vice kept moving on me slightly and at first I nearly pressed the drill in the wrong place twice on one hole (Gotta sort out a better way to secure the vice).  Upon further examination you can see that my two near-misses over on the left actually severed one of my lines.  It shouldn't be too hard to bridge that with some solder or a little piece of wire.  I think I can make it work.

You guys see any other issues?

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Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: madbean on July 20, 2010, 07:05:39 PM
Traces are a little fuzzy and pitted in places, but you should have no issues. Just dab solder over any area that looks sketchy.
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: Haberdasher on July 20, 2010, 07:33:37 PM
Thanks Brian.

I think I may have been a little to aggressive cleaning off the toner prior to etching and that resulted in some of the fuzziness.  Also, you can see the areas I tried to fix with the Sharpie, which didn't work too well IMO.

Hey, is there any reason to clean the toner off before drilling?  It seems like it would be easier to see the contrast if you left it on...
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: gtr2 on July 21, 2010, 04:59:52 AM
I used a dremel engraving bit for my last board.  I forget what size.  I use a dremel and the engraving bit freehand with the pcb quick clamped to a piece of wood.  Boy is it fast doing it that way if you have a steady hand.  Only took a couple min, It turned out great.  The nice thing is the engraving bit doesn't break nearly as easy as a small drill bit.  Just my 2 cents.  I left the toner on until after I drilled as well.
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: madbean on July 21, 2010, 05:03:52 AM
Resharpened carbide bits will last a long time. A single bit can easily drill a couple hundred boards. I say "re-sharpened" because they are much cheaper than new bits.

HSS bits work okay, but will go dull after only 5-6 boards.

http://drillcity.stores.yahoo.net/10pacresdril.html
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: Haberdasher on July 21, 2010, 01:12:51 PM
About the same deal on my 2nd attempt.  Maybe slightly better...
I think if I just run some solder over a couple of iffy parts I'll be fine. 



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Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: madbean on July 21, 2010, 02:14:04 PM
These are fine, really. Just keep practicing. I get results like this, too, sometimes, but I tend to throw the really bad ones out.
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: pigyboy on August 27, 2010, 03:26:26 AM
Hey all,
I ordered some bits from Drill Bit City. Decent price I thought though the shipping was steep.  I got 2 sets of 10 bits for about $17 and shipping to Spain was another $17. When they got here the postage label was $6.50. OK, I can understand some cash for the box and maybe some admin costs but almost triple the actual cost is stealing in my mind. I wrote to them to ask and still no reply. The bastards.....
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: madbean on August 27, 2010, 08:53:12 AM
Yeah, their shipping is a little steep considering it's such a small package. But, it does balance out with the good price on bits. A pack of 10 should last a long time...it does for me even at the rate I drill!
Title: Re: Ideal Drill Bit Size/Range for PCBs?
Post by: pigyboy on August 27, 2010, 09:08:20 AM
Yeah, It just would have been nice to get a reply :'(