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Subject: Re: [Homebrew_PCBs] Re: Minimum Pad Size for Homebrew Single Sided Boards?

From: Harvey White <madyn@...>
Date: 2010-04-06

On Mon, 05 Apr 2010 22:56:10 -0000, you wrote:

>In my relatively limited experience, one of the key factors is how precisely you can drill. My most recent board has .045 diameter via pads, drilled with a .6mm drill (0.024"). Even though I managed to get the registration between the top and bottom more or less perfect as far as the toner transfer and etch, I discovered that it was easy to drill the holes at an angle, at least using HSS drill bits. The drill is so small that it bends very easily; you can be off-center just a bit; the bit goes in right (because of the little etched dimple created by my software), but it comes out in the wrong place.
>
>Obviously, I need to work on my drilling, both equipment and technique!

Carbide bits do not bend, they just break. This is the first example
I have seen where this is an advantage. High speed spindle is a very
good idea, 20K RPM and up is better.

Drill press only.

Harvey

>
>--- In Homebrew_PCBs@yahoogroups.com, Chris Maness <chris@...> wrote:
>>
>> What is the minimum pad size (in mils) for home made PC boards? (Single
>> Sided).
>>
>> Thanks,
>> Chris Maness
>>
>>
>> [Non-text portions of this message have been removed]
>>
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