Thermal Tranfer Test Print - Page 1
Forum section: electronics / beginners

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: November 07, 2014, 03:08:41 am
content: I picked up a laser jet and a couple pcb and I wanted to see if anyone had a Test print I thermal transfer to a pcb to see min and max trace lines ,hole sizes ,and etc etcThanks

author: bance
author_rank: Contributor
timestamp: November 07, 2014, 07:44:16 am
content: Here you go Jason,I've forgotten where I got this, so kudos to the OP.....Hope this helps, Steve

author: Whales
author_rank: Super Contributor
timestamp: November 07, 2014, 07:55:00 am
content: Your resolution results will vary depending on how well you thermally transfer the toner. Depending on your toner and the temperature of your iron, too little time+pressure can poorly transfer the toner, and too much can 'squish' details.If your results are not great the first time, try changing things around a little. My first toner transfers were garbage, but I found using extreme ironing pressure made them work much more reliably.

author: BradC
author_rank: Super Contributor
timestamp: November 07, 2014, 08:56:45 am
content: Quote from: Whales on November 07, 2014, 07:55:00 amLet me give you a leg up, as I've wasted an entire packet of pcbfx transfer paper and 2 laminators to discover this blindingly obvious thing...The PCB *must* be clean. Not clean as you and I think clean, but chemically clean. I had been getting variable results. When it worked, it *really* worked, but I would lose parts of the pattern or it'd smear and often take me 10 goes to get a good transfer.. I tried in various orders :- running the board through the laminator more and more times (up to 10)- Pre-heating the board in the oven- Putting the paper in a makeshift humidifier to soften it up a bit- Changing the toner density / fuser temperature in the printer- Rinsing the board in varying alcohols (methanol, ethanol, isopropyl) and ketones (acetone, MEK)- Giving up and putting the whole thing in the bin- Borrowing another laser printer- Having PCBFX send me some more pre-printed test sheets- Changing the PCB laminate supplier- Facing east- Praying to AllahTurns out I've been using "gumption" cleaner to clean the boards and it's not as abrasive as the cleaner PCBfx recommend.I've taken to giving the board a wash with normal dish soap and some 2000 grit wet and dry. This gives it a nice even grease free shine which passes the "water break" test and now my prints work 1st time, every time.I'm using a very cheap (~$20) modified laminator as per the Ultrakeet web page and I now get consistent results down to 8/8 mil (and I've done as low as 6 between SOIC pads). Best results with 1/2oz copper board, but if I'm careful I get things to work on normal 1oz board. Etch with HCL/H202. If I'm only going as far as 10/10 spacing I just etch with cupric chloride as the extra time taken is not as critical.It took me a lot of head banging over 2 years to finally figure out what was wrong with my process, so I hope this saves you some hair.I drill the boards with a Proxxon TBM220 and I can reliably get holes down to 0.2mm (very fine feedthroughs to go under QFP ICS).

author: Whales
author_rank: Super Contributor
timestamp: November 07, 2014, 09:10:12 am
content: I've also gone crazy at times trying to work it out. Days spent without decent results -> anger and disappointment. Repeat a month or so later when I try againI use steel wool to the same effect. Rubbing with metho helps a bit, but not by much, unless the board is very dirty to start with.

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: November 09, 2014, 07:59:01 pm
content: Thanks Bance ....I was looking into building my own test print using DesignSpark ... I am just need to know what size traces I should start with and end with? What size hole and pad diameters?? Are there and designs I should use for the traces so I can best see how each trace will come out?Thanks

author: BradC
author_rank: Super Contributor
timestamp: November 10, 2014, 01:58:15 am
content: Quote from: TorqueRanger on November 09, 2014, 07:59:01 pmI can reliably get 8/8mil with the Pulsar Pro paper, but unless I need it I set design rules for 10/10, and default track widths of 15mil. 0.8mm holes for all components, 60 mil pads for components and IC's have 50x100mil round rectangle pads.When I'm doing them at home I resize all holes to 0.2mm before i print. That way I don't need to be so accurate when drilling them.