Homebrew PCBs

Stefan Trethan wrote:
> But how does it work then? with the stainless pots?
> I took a really strong magnet minutes ago and there was no force at all 
> with the stainless
> pots. the bottom is very thick on some, but still no force at all.


   Yes induction works fine in copper.  Copper plates work quite well for 
magnetic braking etc.  Take a medium sized NIB magnet that's a close fit, and 
drop it down a thick walled copper or aluminum pipe and note how slowly it 
falls.  Something like iron that takes a weak field will probably be more 
efficient at heating up but that won't stop copper from working as well just not 
as fast.

   I think the thinness of the copper will be the real problem, much of the 
field may not be going through the copper.  Really depends on frequency and a 
few other factors, go high and it should become RF type heating if you can pump 
it out.

   I don't really see any advantage over a normal iron or other heater with it 
though.

   I have been looking at a flat pan or griddle type system.  A low (for cooking 
anyway) even heat, hold the paper and board above it to preheat the board, then 
lower and press firmly into the surface to make the transfer.  Should be notably 
superior to either an iron or roll laminator.  But I've got about ten other 
projects ahead of it, and an iron works fine for the boards I make so this one 
is low priority for me.

Alan