I wouldn't use hinges, but the horizontal from the back to the front, a 
pair of 2" to 3" wide x 1/4" or 3/8" wide plywood strips. Outer face 
grain should be parallel to long sides. Glue blocks all corners to back 
vertical. At the Dremel, a piece of all thread (#10 or 1/4" size) to 
clamp Dremel in position. The plywood will bend under light pressure, 
but will be exact location horizontally which you need. Even very slight 
slop in hinges will be magnified by the length of the arm. If using 
hinges, need 2 pair, and at each elevation the pair should be spread out 
say a foot to minimize location issues. Also would need need a spring, 
that the plywood acts as.  :)  Think there was a picture of this setup a 
week ago.

solarwind wrote:
> I just bought some carbide bits from ebay. They're not too expensive (I 
> think) 
> http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&item=150350480017&ssPageName=ADME:B:EOIBSA:CA:1123. 
> The bits are 1/32" with 1/8" shank. Fit perfectly in my Dremel. I'm 
> going to make a very simple drill press like this: 
> http://www.instructables.com/id/PCB-Drill-Press-Using-Salvaged-Door-Hinges/ 
> using a few pieces of scrap wood and door hinges (I'm going to look for 
> the ones which don't wiggle around). I calculated the amount of 
> horizontal movement for the bit. For a 1" vertical motion, the net max 
> horizontal movement for the bit is around 1 mm. Of course, the PCB is 
> very thin, and vertical movement a lot less than 1" is required - 
> resulting in very very small horizontal movement for the drill bit. 
> Therefore, this design seems to be effective for my purpose. I hope this 
> works out.
>
> Note: my Dremel has a top speed of around 30 000 RPM - should do the 
> trick nicely. Also, I'm going to buy the thinner 1/32" FR4 copper board 
> (as opposed to the 1/16" FR4 copper board that I have now). Easier to 
> cut, easier to drill, more flexible and cheaper.
>
> I wonder why paper phenolic boards are so hard to come by these days... 
> I bet they're easier to drill and much less of a hassle for hobbyists.
>
>
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