Re: [CAD_CAM_EDM_DRO] Re: milling circuit boards

As others have mentioned in this thread, milling is problematic if you are
using thin tracks; the other problem I have found with the milling
technique is that, unless you clear the areas between the tracks (either by
area clear milling or by peeling the copper off the board), milled circuit
boards can be a pig to solder up because of the ease with which you can
create solder bridges to the lands between the tracks.

The method I now favour for quick-and-dirty prototype boards is to print
the layout on a lazer printer and transfer the toner to a carefully cleaned
copper clad board using a domestic iron. If you use a glossy photo-grade
inkjet paper you can soak off the paper, leaving a perfect laser toner
resist pattern on the board which can be etched using conventional etchants
(ferric chloride etc) in not very many minutes. The transfer technique
isn't great for very fine tracks either, but will (in my experience) handle
finer tracks than milling and can be significantly quicker.

Regards,
Tony


At 15:06 06/10/2006, you wrote:

>--- In CAD_CAM_EDM_DRO@yahoogroups.com, R Rogers <rogersmach@...> wrote:
> >
> > Those services aren't free or even cheap compared to taking a $4
>piece of board and milling it yourself.
>
>
> >
> > Speaking of, does anyone have a small board layout that can be
>ran with like a 1/8" endmill? If so and wouldn't mind sharing it,
>please email to rogersmach@...
> >
> > Something in Bobcad or DXF format, doesn't matter what it is.
> >
> > Thanks, Ron
>
>
>Don't forget that if you come home on Friday and layout a simple
>opto-couplier board for a parallel port for you new laptop, you have
>to send out for 3 boards and spend about $60.00 and wait until
>Wednesday to get it.
>
>Or, drop in a hunk of PCB materal, etch and drill it, with holes
>perfectly lined up, and be soldering it in about an hour. and just
>the on board, not three.
>
>As for test boards, I don't get boards in DXF, because my WinQCAD
>exports directly into G-code.
>
>I need to make a opto-isolator for a parallel breakout board.
>
>if you want a copy of that,I can send that once I find out which pins
>go which way.