Homebrew PCBs

jcarlosmor wrote:
> I am using a medium size office laminator without any problems. The 
> film adheres so well, so I beleive that the correct temperature is the 
> key for success. I had noticed also that bubbles or wrinkles are mainly 
> due to operator human error by manipulating the film, just before 
> entering the hot rolls, not the process itself inside the laminator.  
> However, large PCBs in the horizontal axis are more prone to wrinkles 
> because it is harder to keep the film flat with the hands at those 
> sizes. It would be very useful to adapt some kind of roll support or 
> clamp to a structure containing the laminator itself, to emulate a more 
> professional laminator with a flat film entering the hot rolls. Your 
> wet method seems very well, but there are more steps to follow than in 
> the dry method.

Yea it can be a bit labour intensive as DJ mentioned. The water can make 
it a bit of a mess too. Originally I was applying it cold and heating 
after it with hot air, but this cause serious problems with trapped 
water which leads to poor adhesion. Seems my method hasn't much value 
after all. The new squeegee board thing I'm using was an attempt handle 
large sheets of photoresist without it all tangling up. I suppose the 
water method helps with bubbles and the dreaded trapped particles.
My new method takes me about same time and effort to make a cup of 
brewed tea, so I'll stay with it for time being.

I've seen the the professional dry film laminating machines, and they 
have lots of rollers. 2 heated rollers for lamination, 2 protection 
backing film removal rollers, and 2 rollers that carry the photoresist. 
I assume all rollers are all carefully aligned to avoid wrinkles and 
film warping. Two human hands cannot archive that control. I too found 
actual temperature isn't all that critical. It does need to be above 40C 
though using the wet method.

Adam