" DIY your led MCpcb " Procedure Notes:
Pre-print :
-'Mirror' only "through hole *" pcb desings ,( *for under layer of FR4 pcbs ,where pin parts will be soldered )
-Do not 'Mirror' Surface Mounted Device desings .(i.e. like for a led mcpcb .. )
Printing :
-Choose "pre-printed paper " at printer's paper choice. Darkest contrast setting .Finest Quality .
(You want as much toner as possible in the transfer paper ...)
-Choose a paper of S.market/ fast food /pizza delivery /shops catalogs & flyers.
Something that almost sticks to your fingers ,if lightly sweaty/spitted/licked/wet ...
Finding the right paper is the biggest secret of success,in the whole operation ...
Right paper will transfer immediately (stick ) to hot, iron pre-heated mcpcb ..
Right paper will come off with only few drops of water (! ) ,leaving a clean & smooth transfer on copper...
Transferring :
-Place kitchen paper over pcb and let iron on top to preheat pcb (for about 15-20" )..
-Set iron to max ...
-Transferred parts will show(and 'feel') as bumpy traces ,as you iron ...
-Pay attention to corners and edges ..
-Do not overpress with iron tip ...Traces will "bridge " ( toner melts and ..flows ... )
-iron carefully the whole surface ,lightly with iron tip for details ,
iron blade sides (' cuts '... !! ) and "back " of iron ( most commonly a flat "Spatula" shape . ) for larger copper pours or smd areas ...
At end ...wet your hand and whipe it over paper ...
A bit of water...
Then iron over wet paper ,just a tad ...
The steam will make -hydrophobic-plastic toner traces to move away from -hydrophilic-paper ,to copper surface.
Toner totally "un-binds" from paper ...
It works ,trust me ...
Or if it's a steam iron ...
Just give a quick blast of steam at the end ....
Etching:
Metal core pcbs ....
Sodium Persulfate .
It' does not seem to react with aluminium ..
...(Or the alum forms a protective coat .... )
It turns more blue as it absorbs more copper...
Relatively (to other stuff ) safe ...Relatively ...
You can use it on (realy dilluted with plenty of water ..) as soil /plant spray/ anti -fungus primer , when totally "dead " ..(does not etch anymore ... )
It's Copper Sulfate ...For plant's fungus diseases & wall/wood /cement/fabric fungus infestations it's just perfect ...
Caution :It is poisonous ,ya know ,huh ?
Heat the etching solution to 40-60° C ...
Continuous stirring really accelerates the etching procedure ..
Wash your pcb and hands , with plenty of water after etching is finished ..
Good Luck ,Brave ones ...