Homebrew PCBs

--- In Homebrew_PCBs@y..., "crankorgan" <john@k...> wrote:
> Hi Steve,
>          I milled that one with a Brute. I orignally designed my
> mills so people would have a machine to learn on. Someone asked
> me if I could design a mill that would do circuit boards. My first
> machines would mill, but the traces were not that good. It wasn't 
the
> threaded rod. It was my drive nut! The wider the drive nut the less
> backlash. I now use 1/2" wide Delrin tapped with a good 1/4-20 tap.
> 
>                                            John

Hi John, nice looking board!

Have you ever tried a smaller cutter and doing traces between DIP 
pins?

I've also read that a longer nut will reduce backlash. Have you ever 
tried one of the long nuts used to cnnect 2 pieces of all thread 
togeather? Of course with a good tap in delrin your probably getting 
most of the backlash out anyway. 

Another option is to split the nut in the direction of the rod (on 
one side) and slightly pinch it to eliminate even more backlash. This 
technique works better on standard threads than on Acme threads due 
to the angle of the threads.

mike