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Topic: Toner Transfer - My First Shield (Read 4766 times) previous topic - next topic

P18F4550

Mar 13, 2010, 01:51 am Last Edit: Mar 13, 2010, 10:36 pm by Funky_Gibbon Reason: 1
Hi All, so made my first shield today, it's totally useless functionally, just 16 multiplexed leds, mega blink demo, haha.
but the point of this shield was that i've been using the proper blue toner transfer media at nearly £20 for 5 sheets, making prototyping expensive, then i read about people using glossy photo paper for toner transfer so i bought some cheap and nasty Tesco own brand glossy photo paper at £2.04 for 20 sheets and so far im very impressed with the results, i never had much success with the proper blue plastic sheets but this photo paper works great.




TchnclFl

Double sided?  Cool!  Care to enlighten me as to how you managed to get it aligned properly? :)

MikMo

Yes that was my first thought too :-)

cr0sh

Maybe he used my glass panel alignment idea in an oven (not likely, I suppose).

Maybe he got lucky? Maybe he fudged things so much that with enough slop (big drills?) it wasn't any problem if he was off by some small amount?

WE WANT ANSWERS!!!!

;D
I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.

mowcius

Yeah has this been documented anywhere yet?

It looks better than a lot I have seen done with the proper stuff  :)

Mowcius

P18F4550

#5
Mar 13, 2010, 02:26 pm Last Edit: Mar 13, 2010, 02:29 pm by Funky_Gibbon Reason: 1
Alright, well this was my first attempt at a double sided board and it's not perfect but the tollerances were close enough not to matter, this was just an exercise, firstly i make the hole sizes 0.3mm so the drills centralise better.
after printing and cutting out the circuit on the photo paper i used a 0.6mm drill on arduino reset and digi pin 0 rx on both upper and lower circuit printouts, this gave me two alignment holes, then i layed one printout on the copper board and drilled again with 0.6mm through the two holes i made in the paper, this gave me the allighnmet holes in the board, next i used two short pieces of 0.6mm solid core wire, put them in the holes in the board and slotted the paper transfer onto the two wires and used the clothes iron to just briefly tack down that side, then turning the board over i slotted the other transfer onto that side and tacked it down before removing the wires and going through the transfer process properly.
In theory the should have been aligned but i was sloppy with my drilling and didn't get the hole exactly vertical, it meant that one side is maybe .25 - .5mm miss aligned but it's enough and the board works, finally i drill all holes out with 0.8mm.

I think next time i will add some alignment hole off the pcb, but as i said this was a learning curve as i've only made single sided boards before.
The mess around the pad is from a flux pen which i didn't think worked that well, that was a first time for me too, normally i would clean the pads up with a fibre glass pencil and that seems to work better

TchnclFl

Well done!

You can clean up that flux with some isopropyl alcohol (rubbing alcohol).

Mark S

P18F4550

Very nice, could you post more details and maybe some pictures of the process you used to make the board.

Thanks

beige

oo, nicely done 8-)

I made a few PCBs using toner transfer, but never managed good results, the odd track mask would always lift...

TchnclFl

I just noticed:  Did you accidentally graze that button with a soldering iron?  The top looks all melty ;D!

P18F4550

no, the button was too long so i cut it down, messy yeah

TchnclFl


P18F4550

#12
Mar 14, 2010, 12:18 am Last Edit: Mar 14, 2010, 12:39 am by Funky_Gibbon Reason: 1
Ok so as requested this is not a How To but a How I Did

Design the circuit, i use PCB Wizard


After printing the design to the photo paper carefully cut out the transfers, i print them on a laser printer with settings of paper type = transparency and density = 9 (highest)


Cut the copper board to about the right size leaving a bit extra to account for burring of the edges


Clean off the burred edges with a file and then i clean the board with Cif cream and a pan scourer, this is the important bit so take time to be sure the board is clean, when you rinse the cream off if the water runs straight off the board then it's not clean, if the water remains then it's clean


Dry the board and put it between a folded piece of paper and pre-heat the board, this ensures that any remaining water is evaporated


Next i use acetone (AKA Nail Polish Remover) to clean and remove and residue of Cif cream and grease


Drill two 0.6mm holes in the paper transfer, anywhere but be sure to drill the same two hole in both top and botom transfers


Lay the transfer on the board and with 0.6mm drill mark the board by drilling through the holes in the transfer, this is also a critical stage, be sure that the holes in the board are as vertical as posible or the pads won't line up on the bottom side,then using a couple of pieces of 0.6mm solid core wire to line up the transfer with the alignment holes in the board.


With the hot clothes iron tack down the top transfer then turn the board over an line up the bottom transfer the same as the top by using the two pieces of wire and tack this side down with thiron too


Slip the board between the peice of paper and apply heavy preasure with the iron set to hottest setting and no steam, hold the iron there for greater than 30 seconds, take the board out, carefull it's hot, turn the board over and apply the same preasure to that side, the metal plate is not nessisary but i use it as a heat sink, not to disperse the heat but to hold the heat and hopefully keep both sides of the board at an even temperature


Use the tip of the iron and work your way over the whole surface of the board until the traces under the paper start to show through, be very thorough here and make sure to iron every part of the transfer, turn the board over and do the same on that side


All traces show through, i think it's ready


Drop the board into some warm water, leave for 5 minutes for the paper to soak


Gently rub the paper with your thumb and the paper will seperate, the white substance left behind is the glossy coating of the paper, this will also rub off



When all traces of material have washed off it's ready for etching, notice there are a couple of bad spots in the toner, this might be because i rushed these pictures and didn't clean the board enough, or wasn't thorough enough with the ironing process, either way they can be touched up with fine tipped permenent marker pen


I hope this post will be of some use, this time i took more time over the alignment and the pads lined up perfect, so i guess time and patience is the answer.
A silkscreen can be applied with the same transfer method one the board has been etched.

programmer

You can get the toner transfer sheets cheaper on Ebay, I usually get 10 for £5 from China and they work ok.

Alternatively, I`ve read that pages from colour magazines with the glossy paper or some catalogues works really well. Haven't tried this out yet, but read a number of reports saying it works in various places.

TchnclFl

Nice little guide, and I love the pictures!

I've always heard the toner transfer sheets aren't worth it, that glossy photo paper works just as well if not better than them.

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