Homebrew PCBs

--- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> Hi Tom,
> 
> I wish I had a 25K spindle!  I'm looking at various laminate 
routers.  I
> was using a .093" endmill.  The Phenolic I was cutting made nice 
tame
> swarf, heavy enough not to blow around, and not the "itchy glass" 
dust. 


Alan,

Here is something you could try.  Take a regular drill press and put 
a large pulley on the motor and the smallest possible pulley on the 
spindle. You should be able to find the right ratio to get up to 
25,000 RPM. 

You can then attach a piece of plywood to the drill table and drill a 
hole into this wood with a .125" drill bit. Remove the bit, close the 
chuck all the way and use the chuck to press a .125" dowell pin into 
this hole. Now chuck a .125" router bit and lower the spindle until 
it is almost touching the pin. Lock the drill spindle to this depth 
and you have a pin router. 

You may have to make a new pulley shield since the motor pulley could 
end up being larger than the original shield after the correct ratio 
is established. Make a template the finished size of your board with 
at least two tooling pins and you can route the boards to size. As 
many as three and sometimes four boards deep can be routed this way 
depending on your spindle power. The only negative with this method 
is the Morse taper on most drill spindles can't take too much side 
load but I have seen this method work and you don't have as much 
noise as the Dremel tool and die grinders make. This is similar to 
how the big pin routers work.

I use a commercial pin router and have always been able to out 
perform all but the largest CNC machines. If you are making larger 
quantities this is a good way to get the job done with a small 
investment. I also use pin routers to make my control panels and 
other plastic parts.

Tom