Archive of the former Yahoo!Groups mailing list: Homebrew PCBs
Subject: Re: Mouthwash (Toner transfer tips)
From: "jcoffland" <homebrewPCB@...>
Date: 2007-05-02
I also bought a Brother printer from Staples. HL-2040 for about $80.
I use Staples 'photo basic gloss' item# 471861. I have been very
successful with this method. I am still using the toner cartridge
that came with the printer. There are a few VERY important steps to
make this work consistently.
First, you need to clean all oils off your PCB board before doing the
toner transfer. The method I use which works very well is to first
put on vinyl gloves then using Comet, stealwool and water to scrub the
board thoroughly. When all the oils are gone water will form a thin
sheet over the board. Any oil spots will show up as they repel the water.
Second, I find it helps to rough up the surface a bit with some 150
grit sandpaper. You must also rinse the board after sanding and you
should still be wearing the rubber gloves. Once the board is taped to
the photo paper you can take off your gloves.
When it comes time to iron on the toner, push hard with the tip of the
iron and go over the whole board with little circles until you can see
the pattern show though the paper.
Also another tip. I recommend doing a copper fill for the usual
reasons, but also fill about a 1/4 inch around the board. The toner
on the edges of the board is most likely to peal away. By adding this
1/4 inch barrier you will protect the outside traces. The board can
be cut down later if necessary.
When it comes time to soak the board I can usually pull off almost all
the paper after about five minutes. A thin layer of paper will
remain. I then use a piece of the wet paper I removed to rub against
the board. The wet paper is perfect for this as it is just the right
hardness to remove the paper but not damage the toner traces. You can
scrub as hard as you want but be careful not to scratch the toner with
your finger nails.
Finally, I dry off the board and check under good lighting that none
of the paper's gum is still on the board especially in the small gaps.
As the board dries any residual gum will turn whitish. If there is
any more gum I go back to rubbing the wet paper over it and repeat the
drying and checking process.
All that is left is the etching.
Joseph