Homebrew PCBs

Hi Hans,
        A ballmill or burr as my local guy calls them work. That's
how I started. I used a steel Dremel bit. It went about 12" before
it became dull. I then went with the Think & Tinker bits. I will
have to give the ball mill a second try. This time it will be
carbide!!!  The round tip will allow for variation in board
thickness. I think the plunge speed will have to be changed. Ball
mills like cutting side to side. They are slow cutting straight
on. But if I can get them at $4 each slowing down the Z speed will
still be worth it.

                                             John 



--- In Homebrew_PCBs@y..., HW <hans@c...> wrote:
> John,
> Sure I think Delrin is a wonderful material.
> I looking forward to the fall when hopefully I'll have some time to 
do
> my own projects.
> I've been watching the discussion about mill bits and think there 
may be
> a better solution.
> I'd like to try a 2 or 4 flute ball end mill or square cut about
> 0.007-0.01" in carbide, I think the resulting channel that the ball 
will
> cut into the copper will leave a smooth edge and with the idea of a
> really flat surface ( may be a vacuum bed) adjusting the depth of 
cut so
> that almost no FR4 is cut, then the wear in the cutter should be 
very
> low. With this kind of mill bit it should be possible to do 2 trace
> between normal IC pads ! The bits cost abotu $25 each but may work 
out
> cheaper in the long run.
> 
> Has any one seen or heard of using a laser to cut the PCB copper ?
> Recently I got some samples of Laser engraving and it was in 
aluminum,
> cut was about 0.003" wide ! ideal for PCB etching I'd say !
> Hans W
> 
> I cut most of the thread as it was getting far to long...