Homebrew PCBs

On Sat, 19 Nov 2005 16:28:24 +0100, matt clement <buckeyes1997@...>  
wrote:

> okay
>
> I figured the printer would get oily with the oil method, but didnt
>
> think it would leave the printer too bad off.  I am going to pick up
>
> a tube of RTV silicone today (high heat) and try getting a window
>
> cleaning squeegy to get it on the paper.  i assume you only do one
>
> side right?  Am I looking to get a layer as thick as a "notecard" or
>
> am I trying to get it as thin as as possible?  I would only worry
>
> about getting it too thin in some spots.  I just havent figured out
>
> how to get it to be thin and yet perfectly smooth.  maybe laying
>
> another piece of glass on top and add pressure to get all the air
>
> bubbles out until dry?  IS RTV anerobic?


Don't use a window sqeegee, use a metal one. i dunno what it is normally  
used for but my tools store has them in all widths, i use a 20cm wide one.  
It's made of about 0.5mm thick steel and has a wooden handle.

You can scrape right down to the paper with as much pressure as you can  
without ripping it, holding the sqeegee almost vertical. This will still  
allow easy release, if you peel while the PCB is still warm. If you make a  
thicker layer (so that the suface is just glossy) you can peel cold  
without ripping the toner off, but it is hard to see through if you have  
red silicone. Using even more silicone would seem bad to me since thicker  
material gets less toner density and you don't really gain anything.

ST