Tuesday, January 13, 2009

FAILED: toner transfer

I found some WEAK instructions on the net on how to do toner transfer. All the instructions are week. I followed them as best I could. When i get my method right I will document it unambiguously & very explicitly!
so after ferric chloride, I thought this was a complete reaction... The color of the original copper was different to the reacted copper... Since i know no better, I continue with the next step.
I cleaned the toner off with thinners, cut a piece of chip board, clamped the PCB to the board so that I wouldn't drill holes through my Mom's kitchen table. Got out my manual hand drill & a pack of 0.7mm HSS drill bits.
I start the first hole & snap my first bit imediately!
My Dad decided to help me & we got a bit clever! We unscrewed the handle of the manual drill, then took put the power drill's chuck over the manual's handle. We balanced the drill combo on some masking tape & a small box, there was just enough spring to push down on the manual (red) drill to drill a hole, then it would spring back easily when done. This method worked for a while... then the manual drill's gears, which i assume are made from plastic started failing. All this hassle just because I don't have a drill press... yet...
So I think I'm done drilling... I find out later that i missed about 5 holes. It took 1hr25 to drill all the holes of a Arduino Serial.


After all that trouble, I realize that print out was not 1:1! I'm furious now! In my mind I still think that the board etched properly... The next day the board is black with oxide... So then I realized that I took it out the ferric chloride too soon!
I decided to just place in as many components as I could... just for some motivation... My holes we not straight... some of the headers would never fit no matter what! The manual drill "walks" a bit when you start drilling. The position you intend the hole to be in is seldom where it ends up.

Eventually I will either succeed with my own etching or I will go back to trying to figure out how to lay everything out on vero board. Either way, I have ordered an Arduino with my reprap kit order from the RRRF. I just have to wait for my brother to bring it back from the USA.


Murray said...

Back in the day when I use to drill my own PCBs, I use to lay it out so that all the parts were on a 0.1 inch grid. I would drill the two furthest diagonal holes, use 1mm copper wire to tie a piece of strip board on top of the PCB, to act as a drill guide. Finally on top of the sandwich of boards I would place a piece of transparency or tracing paper with the PCB drawing printed on it.

This, and a drill press speeded the whole operation up tremendously. The only drawback is that occasionally I would have to lift the layers a little to blow out the dusty bits that accumulates during the drilling process.

Mind you, these days, with so many SMD parts, it may be worth it to re lay it out to reduce the drilling.

OuZo said...

Thanks, that's some good solid advice :)

SMD's are just so small to handle... I must work around the block I have over them...