Laser printing DIY PCBs

[Sounduser]

Hi,

Ive been playing with laser printer single sided PCBs. Using the paper than sickers come on. Its working fine.

I was wondering, what is the best thing to touch up traces with?

Sharpie pens dont really hold up while etching. I was thinking some kind of paint and very fine paint brush. Just to go over any holes in the print.

Thanks.

[rdl]

Paint and a fine tipped brush will work pretty well. Back in the 80s I painted a lot of small, simple circuit boards. You can get very fine tipped brushes at a hobby shop, or buy online. Most model paints will work. Even fingernail polish (which is actually a kind of lacquer) will work. Be sure to get some thinner or brush cleaner, too. Make sure you give the paint plenty of time to dry before putting the board in the etchant.

[picandmix]

Find the type of permanent pen that you write on to CDs etc work fine, the one I currently have is labelled Stabilo Write 4 All.
Also the Staedtler Lumicolor Permament should do as well.

For cleaning, thinners as rdl mentions , what I  use, Acetone or cheap Nail polish remover, but use soapy water if using the latter as it contains oils

Not sure what country you are in , so these brands might not be in your area...

[tautech]

Hi,

Ive been playing with laser printer single sided PCBs. Using the paper than sickers come on. Its working fine.

I was wondering, what is the best thing to touch up traces with?

Sharpie pens dont really hold up while etching. I was thinking some kind of paint and very fine paint brush. Just to go over any holes in the print.

Thanks.

2 possible issues IMO.

The copper is not clean enough, sand with 600 to 1000 grit paper or steel wool. Wash & dry. Some pre-etch to get a better toner stick.

More heat and/or pressure in the transfer process.
Pouch laminator gives the most consistant results. 2 passes.