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Want to produce stunningly good quality PCB resist transfers using only a cheap laser printer ($99) and some sticky-label backing paper? Read on and see how easy it is.

I initially thought that my previous method, the print/iron/soak/peel system was the 'ants pants' (as we say here in Australia) but behold, this new method is vastly faster and more consistent.

First up, if you have an inkjet printer, don't bother - it's not going to work, period.

What you're going to need

  • Bare copper clad board (I like using 1/32" but 1/16" is more common)
  • PCB layout to print
  • Cheap laser printer (mine is a Xerox WC3119 combo printer/scanner 600dpi - cost $225 AUD and even works with linux - including scanner!)
  • Good toner cartridge - can't stress this enough, if you're low on toner or you've got a dud photoimaging drum, you're going to have a hard time getting a good transfer
  • Avery or similar labels - I suggest using the 2x7 array labels, for reasons I'll explain later
  • Cheap paper napkins (I buy mine for 99c per 100)
  • Household iron
  • Vinyl lettering transfer squeegee or similar soft plastic edge.

Cut board to size
I like to over-size my board by about 3~5mm all around so as to allow for handling room (fingerprints!) and it also gives you a place to drill a 2.5mm hole to hold the PCB in the etching tank with.

Using tinsnips works great for cutting 1/32 ~ 0.8mm PCB

Clean that board
Really, if you don't get this step right you'll not have success later. You have to get that copper very clean, I recommend using steelwool and scrubbing it till it looks like it has a bit of a mirror finish. The cleaner the board is the better the toner can adhere. Clean the board down afterwards with a napkin and some metho/denatured alcohol or acetone - keep doing this until the napkin wipes clean.

Use steel wool to scrub off the muck

Print the layout
Now, I suggested using 2x7 label sheets in the 'needed items' list, the reason for this is so that you can use the sheet multiple times by exposing a clean backing for each new job. Also, most printers will jam up if you try to feed the glossy backing paper directly because it's very hard to grip it with the rollers. So print a test of your circuit layout onto ordinary paper first, then peel off the spaces that you need from the 2x7 label paper to match up. Finally, print the circuit layout onto the label paper and hopefully the circuit layout gets printed onto the smooth glossy backing paper. Once you've got this printout, make sure you don't fold or crease it else you'll send pieces of your precious toner layout flying as it's barely sticking to that backing paper!

Only remove the labels you need to allow for the printout

Preheat the blank board
Before applying the layout to the bare copper, it's a good idea to preheat the board. To do this, place the board onto a clean surface of wood or one of those 'self healing' mats, then place a napkin over the top.
Turn on your household iron and set it to roughly cotton temperature. Once the iron has reached the desire temperature, place the iron onto the napkin and wait about 60 seconds - DO NOT LEAVE UNATTENDED. A good iron will have a auto cutoff but don't rely on it!

Resting the iron on the napkin on the circuit board.

Apply the circuit layout
Finally, we're getting to the part where action is happening!
After preheating the board, lift the iron and napkin off the board and then place the paper with the circuit print out down onto the bare copper. Hold the paper in place so it cannot move too easially (you'll be surprised how many transfers have been ruined because the iron lead knocks the paper). Place the napkin back on top and then the iron on top again.
With the iron now resting on top of the napkin, on top of the paper, on top of the copper board, leave it there for another 60 seconds.
Now, apply some pressure to the iron directly downwards. Do not move the iron or paper, just put some pressure on the iron for about 15 seconds, perhaps 5kg or so - no more.
Lift the iron off the job, remove the napkin
You should see that your toner layout has bonded to the board and shouldn't be smeared. The edges of the paper will likely begin to curl up - don't panic about this, just don't move the paper around.

Applying the printout to the copper, get it aligned and don't let it move!

Iron heating the printout causing the transfer to the copper

Iron removed, notice how the paper curls up but the circuit area is still holding down.

Removing the paper
Again, while not moving the paper around, take the squeegee or soft edge substance and stroke it across the paper with a light to mild pressure (not too hard else you'll smudge the tracks). If all has gone well as you stoke over it the paper will lift but the toner will not.
Gently gently lift up the paper from around the board and you should see it pull away from the board without leaving any toner pieces. If you get large chunks staying on the paper then either;

  • your iron was too cold
  • your board wasn't clean enough
  • your surfaces aren't flat
If all goes well you should have a very professional looking transfer. Give it a couple of minutes to cool down and then inspect it.
Check over the board for squashed tracks (too much pressure!) or tracks with breaks in them (dirty copper).
Once you've given it the all clear you're ready to go to the etching tank.

Gently does it. By applying a slight pressure to the paper/board it causes the toner to release from the backing paper

See how the paper is lifting away leaving the toner on the board

A professional looking result

Notice how no toner is left on the paper

Fresh out of the etching tank, still looks sharp

The assembled project less than an hour later.