Direct pcb etching

Hey you who make your own diy pcbs. I got to thinking today. They make copper tape to repair circuit boards. So I was thinking why not load alot of copper tape on wax paper, and directly print on it, then peel off and stick it on to non perfurated board, but it would only work up to 2 inch circuit boards, like ones that fit in modules. this is what got me to thinking http://www.instructables.com/id/S7L2S5CFB7FPNKI/

Hmm.

How thick is the foil? If it's thicker than a few dozen microns it might not etch well.
How would you stick it to the board? (edit)Oh, the tape is adhesive I guess right?(/edit)
You'd need to etch it *after* sticking it to the board and you'd need to be sure whatever you used to stick it doesn't dissolve in your etchant and is free from bubbles or any type of gaps, otherwise you'd end up etching underneath, on the non printed side... It would also have to keep the foil stuck firmly in place while sanding off the toner and soldering everything.

By the way, the fuser module in a laser printer (required for etching since laser toner stands up to etchant) gets to very high temperatures. Putting wax paper through a laser printer = fire.

If I were etching my own circuit boards I'd either use the toner transfer process (which I have my doubts about, yet tons of people say works great (rckstr uses this method iirc)) or if I wanted to be ghetto about it I'd draw the circuit in with an etch resistant pen (whiteout works for this) or I'd cover the board in tape and cut the circuit out with an exacto knife.
Copper clad board is cheap as dirt, here's a chunk the size of a sheet of paper for $3.35.

Neat idea though, that instructable opened my eyes to the world of "Pyralux" and gave me renewed hope for replacing flexible ribbon cables in laptops I accidentally rip on occasion, which is completely devastating by the way since it's usually within the LCD and is normally about $200 to replace the whole panel.

the instructable uses a wax printer of some sort...
laser printers work by charging the paper to make the toner stick to it, then run it through a fuser to melt the toner to the paper.
The thing is, with copper because its a good conductor, i don't think it will charge properly, so i doubt you could print to it using a laser printer

Tektronics Phaser uses a "wax" crayon to more or less draw on the paper... It's been outclassed for years by standard color laser printers as far as depth of image, and resolution. Neat idea, though - the regular toner transfer method works just fine for those DIY'ers out there wanting to etch their own boards...

Im just gonna forget about this and make a direct pcb printer out of an epson c67 i bought from the thrift store $3.03, I guess its worth a shot?

So, you plan to print directly onto the copper-clad boards? If a printer had a direct feed-through, meaning the paper wasn't bent around a roller or anything, it might work... but, your Epson is an inkjet, I believe, and the ink will smear right off when you go to etch it, if it sticks at all to the copper. Unless you have a specific method you're working off of?

normal inkjet printers print with water based ink. so it will be useless for etching

if you want a method that is less problematic than the direct toner transfer, try photographic resist PCB's. the only downside is cost of the boards and extra chemicals for developing

SenKat_Stonetek said:

Tektronics Phaser uses a "wax" crayon to more or less draw on the paper...  It's been outclassed for years by standard color laser printers as far as depth of image, and resolution.  Neat idea, though - the regular toner transfer method works just fine for those DIY'ers out there wanting to etch their own boards...

Click to expand...

it actually melts the ink then prints it on a drum, then sticks it to hot paper.
I suppose it uses inkjets to put the wax on the drum... i wonder if a inkjet could be modified with a small heater coil to print hot wax...
I have so many inkjets lying around i might as well try it

The printers they use for plastic ID cards are thermal printers that melt a layer of plastic over a 2x3 inch card. If you cut some copper clad boards to size I think it might just print them.

I'm not positive the plastic would stick to the copper the same way it sticks to the plastic cards, though I imagine it would.. and I'm not sure, most copper clad is thicker than a credit card and I'm not sure the printers can accommodate thicker cards... but if it worked it would be a pretty cool solution that works out of the box.. you can feed it a stack of like 100 cards, and you can fit quite a few drivers on each one...

I have one at work, and I'd try it if I had some copper clad board, but I don't have any circuits I need to etch at this point so I'm in no real rush to get some.

rkcstr said:

So, you plan to print directly onto the copper-clad boards? If a printer had a direct feed-through, meaning the paper wasn't bent around a roller or anything, it might work... but, your Epson is an inkjet, I believe, and the ink will smear right off when you go to etch it, if it sticks at all to the copper. Unless you have a specific method you're working off of?

Click to expand...

Not all rckstr, The brand Durabright Ink, for epsons are waterproof. You have to heat the board first for the ink to stick on and cure properly. You have to take the printer out of its shell and help it feed. It need little modification. Here is were i found it http://techref.massmind.org/techref/pcb/etch/directinkjetresist.htm

Im gonna try it, I thought at first regular ink wouldnt work but then i read about it more and some do.

I figured you had something up your sleeve I just wanted more info ;D

Ill take picts of the build, If its more effecient and give better etched boards then I guess it would be worth it.
Also upon reading, lots of people say that ferric chloride is more aggressive than the muriatic acid/peroxide mix when etching.

ok running a normal inkjet on wax doesn't work  
lol i spent ages making a heater to melt the wax and heat up the print heads to 70C only to find that the thermal jets don't work with liquid wax
maybe piezo electric jets would work, but i don't think its worth it...
i will stick with toner transfer

Oh i also found that when i preheat my boards with iron that i get perfect tanfers and no need for going over with marker

So I decided to use an HP 890C printer, I bought waterproof ink refills as the original ink isnt waterproof.