Very crappy LaserJet III printer, the faint smudges don't seem to interfere greatly, but the pin-holes do. The transfer invariably needs a bit of rework with a fine-tipped permanent marker pen.
The ad pages from InTech magazine, American edition, give great transfer.
Cut the blank to size, scrub thoroughly with dry steel-wool, clean it with several passes of paper towel wetted with isopropyl alcohol. It's fundamental to have the copper slightly rough and very clean. Any fat or finger-print will cause the transfer to fail.
Cut out the print with some margin left and right, place the blank upside-down over it, align and fix in place with pieces of white label. Turn over.
Set iron between cotton and linen, let warm up for 10 minutes. Pass directly over the paper evenly for some five minutes, press with edge a few times. Otherwise no great pressure seems to be needed. Once the copper is hot enough to melt the toner it adheres right away.
Let cool off and soak for some time, say five to ten minutes. Gently pull off paper. I usually print more than one copy since the first try usually gives more defects than it's worth the hassle to correct.
I mostly do single-sided, but for the few double-sided the following worked well. Use alignment marks on the artwork. Transfer copper side as above, don't etch. Drill very fine holes through the marks, make pin-holes through the corresponding marks on the component printout. Push pins through the holes in the blank, use them to align the printout. Fix in place, remove pins and apply iron. Etch both sides at the same time.
Etchant is copper chloride, several years old by now and getting better over time. CuCl2 is a bit of a job getting started but once working it's great.
--- On Sun, 1/24/10, howdee_20 <howdee_20@...> wrote:
From: howdee_20 <howdee_20@...>
Subject: [Homebrew_PCBs] Discussion on Toner Transfer Method
To: Homebrew_PCBs@yahoogroups.com
Date: Sunday, January 24, 2010, 4:59 AM
Hello All,
Circuit designing has been my hobby for long time. However, i always found it difficult to make a PCB as there are no screen printers near my area and being a Embedded programmer i didnt wanted to jump in the time consuming process of PCB Manufacturing.
Couple of months ago i found out the "Toner Transfer" method for PCB manufacturing. However,for a newbie its still a matter of trial and error. So guys here i wanna start a discussion with all those who have done this process ( Sucessfully or not ) , to share their experiences and conclude with a perfect , cheap PCB making process, which can be implemented easily through TONER TRANSFER METHOD.
To maintain relevency of discussion let me point out few topics for discussion:
1. Paper used for Toner Transfer
2. Laser printer type.
3. time and temp. required for exposure ( imp)
4. Single sided and Double sided PCB designing.
5. CHEMICAL composition and eatching time.
etc..
[Non-text portions of this message have been removed]