Member @gordonendersby recommends this page
http://milksnot.com/content/toner-transfer-method as an introduction to the toner transfer method.
Does anyone have any recommendation on specific papers to use?
I use good quality paper from old magazines.
Slightly shiny with not too many pictures so you can see through to the toner printed on it.
Taped to a sheet of a4 with masking tape.
Ive had very good results like this.
Tried special papers and didnt get on with them.
Gordon
What did you etch with? The article above isn’t entirely clear, but I’m guessing copper II chloride? I’ve only ever used iron (III) chloride…
Ferric chloride is what ive used.
I could always do another demo on a μMeet evening like i did at the shop.
Allthough we didnt get a big takeup last time.
Might have just been while everyone was on school holidays with kids though.
Gordon
I’m not actually doing PCBs. In trying to prep brass sheet for acid etching of graphic images (anyone recognise them?)
So for me a little broken line isn’t too important whereas for a PCB it would be a disaster…
I am finding not surprisingly that the brass sheet needs a lot of heat to get warm.
Also the transfer seems inconsistent and affected by the graphics that were printed on the original page. Not sure if this will transfer to the etch…
This is the first attempt. Second had more heat and I think will work better.
How big is the sheet?
I use a laminating machine to put the heat in. With several passes. Gets the copper clad board nice and hot.
You can see when the toner lets go of the paper.
Also soaking off the paper in some warm water is important or you can lift the toner a bit.
Gordon
Theres no reason to put up with broken toner lines.
Just fill in with a black sharpie or similar.
These is the biggest board i did with toner transfer. The traces are quite sharp.
http://scratchpad.thisandthose.org/scratchpad/article.php?story=20100715160140327
But then im taking a single layer of copper off the board not etching to a depth like you.
The etching solution will eat under the edges of the toner if you leave it too long making the edges rougth.
Gordon
Good work @gordonendersby
If you do another demo I’ll try and make it this time!
I’m thinking along the lines of having my boards made for me when I eventually get around to designing something. It’ll just be a board to plug in an Arduino Nano, an NRF20L radio package and maybe a sensor or two, or the facility to solder in a MOSFET instead - a general purpose IoT thing that will talk back to a Raspberry Pi.
The last PCBs I made were designed on a cad package and made using a UV exposure box and bubble etched in ferric chloride - but I had access to a school DT workshop then!
Another method…
Hi, this is delving back into the history books a little, but I’m wondering whether you got this to work at the makerspace. After a bit of reading on the internet there appear to be various ways of combining the laser cutter and acid etching to allow you to etch copper or brass. Getting the laser cutter to ‘engrave off’ some sort of paint from the metal before then putting it in the acid bath seemed the way forward - did you get this to work at all?
Yes, but I didn’t use the SLMS laser cutter so I can’t help with settings I’m afraid.
Chemistry teacher friend found me some FeCl3 
Ok, thanks, will do some more reading and try to find out whether it would
be possible at SLMS. Thanks again, Simon.
There’s no reason why it shouldn’t.
Just used a cheap black spray paint over the copper, and etched a few test speeds first.
I think you can get FeCl3 from Maplin if we don’t have any in the space. @electrotechs?
Acetone is useful for getting the paint off after etching.
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I have some blue transfer sheets made for laser transfer. Bought them for a project that didn’t use them in the end… shall I drop them over Thurs ? Supposed to be as easy as print design on the sheet, iron on blank pcb and etch in ferric chloride.
Courty
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The only problem with etching is we don’t have a way to dispose of it and it can’t go down the sink.
thanks @Courty , that would be great. I’m not really an electronics person but think it would be good to get some advice on etching so will be there on Thursday.
Simon.
Will try to dig it out and bring it along…
@unknowndomain - I seem to remember a gell that could be added to spent FeCl3 that made it set so it could be thrown in the bin… it was a long time ago so no clue as to what its called ?!
Courty
Yeah something like that.
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