Homebrew PCBs

Arnie,
      A mechanical etch bit will do two 4" X 6" boards with lots of 
traces if you run it at 16,000 rpms with a 6" feedrate. If you 
increase the rpms you might see runout in the motor tool. Runout is 
the slop in the bearings along with a poorly balanced armature. You 
will also see bits break. The bits are solid carbide and the tip is 
very thin. The tip is shaped like a drill bit. Three drops of motor 
oil spread on the board will keep most of the dust down. I have 
pictures of my milled boards in the pics section.

                                                  John




--- In Homebrew_PCBs@yahoogroups.com, "acfrankenberger" 
<acfrankenberger@y...> wrote:
> Sorry for not being clear in my first post.
> I am actually planning on using a separate spindle (a dremel like 
> device) attached to the Taig. It will do up to 30,000 RPM.
> 
> Thanks,
> Arnie
> 
> --- In Homebrew_PCBs@yahoogroups.com, "crankorgan" <john@k...> 
wrote:
> > Arnie,
> >       The spindle speed on the Taig is toooo slow. You need 
16,000 
> > rpms to mill circuit boards at 6" per minute using a two fluted 
> > mechanical etching bit. What is your top speed  10,000 ?
> >                                            John 
> > 
> > 
> > 
> > 
> > --- In Homebrew_PCBs@yahoogroups.com, "acfrankenberger" 
> > <acfrankenberger@y...> wrote:
> > > I have a Taig mill I was hoping to use to mill out (trace 
> > isolation) 
> > > and drill some circuit boards. Would phenolic based boards make 
> the 
> > > milling process less demanding on the tool bits?  Could I avoid 
> > dust 
> > > collection?
> > > 
> > > Does anyone have a source for phenolic copper clad boards?
> > > 
> > > Thank you,
> > > Arnie