Who would have thought that some corn starch could be made into toner transfer paper? We’re not sure of the advantages (perhaps its cheaper?), but if you have a lot of time or just love to get sticky [Matthew Sager] shows the proper method for making the paper, printing, and then etching a PCB.
If you’re just getting started making PCBs, we recommend you check out these DIY circuit etching videos to get a better grasp on the printing and etching steps.
this is pretty cool will try for myself soon
while cool it seems like a lot of work, I just go to my mailbox
what is it for ?
why to always try to recreate a simple process ?
it is so easy to print on transparent sheet and transfer with any uv lamp on photosensitive board
photosensitive board or spry isn’t available in many places including Egypt (my country) !
why does he even soak the paper and fiddle around with that cornstarch. just use some standard coated paper from offset-printed magazines!
Or just use glossy photo paper.
@tim
Actually i like the toner transfer better than the photosensitve one because:
– I’m a student living in a small appartment. I already have a laser printer and cloth iron, but i don’t want to store an additional exposure device.
– I only have to mess with one chemical (NaPs) instead of 2.
– I’m a broke student, the simple copper clad boards are cheaper than photosensitive ones. Transparent sheets are also a bit expensive here.
– Its just less clutter. I print out the design, iron it a few minutes, throw it into the sink or a bowl with ordinary water to dissolve the paper. And then comes the only step that i have to be carefull about: putting the board into a container of the etching solution for a couple of minutes.
@osgeld, Lars
For my printer the magazine paper doesn’t seem to work that well, it seems to deposit too little toner. The glossy photo paper works quite good, and i have a stack of 100 sheets still here from some discounter shop.
But if i have some time during the sommer, i just might make myself some of this paper to store for the future (If you do a run of 200 or so papers, it might be worth the hassle)
Articles like this are awesome and the reason I started reading Hack A Day. We want to see more of this!
The movement to start doing reviews and commentary on software just makes me sad. :'(
That’s a good trick, especially if you don’t have a printer that’ll deal with magazine paper. My old one would jam on it relentlessly. My HP1006 has no problem with it, though.
I made a test pattern to test my home fabrication capabilities. http://dorkbotpdx.org/blog/laen/adventures_in_etching_the_test_pattern
I think that’s useful to see what kind of design rules you need to impose on yourself.
I was working on another test pattern (that included trace clearances, not just trace widths), but nowadays I do a group pcb order (http://pcb.laen.org), so I think my etching days are behind me..
The cornstarch coating is probably similar to the coating used by press-n-peel or pulsar profx, which use a starch coating to make the toner release step much quicker. This is vastly superior to the magazine paper / photo paper transfers i’ve tried before in terms of transfer time–one or two passes in the laminator, and dip the transfer into a water bath for 1 minute (literally! and virtually no mechanical agitation necessary!), and then etch. voila! it’s much faster–I’ve never actually gotten a process with magazine transfer working properly (failed every time i tried using it), but iirc it wasn’t nearly as easy to remove the transfer paper as it is with a starch-coated paper.
For those of us in college who cannot afford to have their boards fabricated, or use photosensitive boards, this is a nice option. Photosensitive boards don’t exist in all sizes and they are hard to find for fairly cheap. And I don’t make enough boards to justify buying photopaper. However I have cornstarch in my pantry already. So this is a good find. :)
I would not recommend doing this in a printer you rely on. As someone who used to repair printers for a living, I’ve seen my fair share of damage done to printer components due to nothing more than using cheap paper, let alone running masking tape and coated paper that is surely shedding fun particles on the drums and rollers…
On that note, if it *does* damage anything you can be pretty certain the warranty will not cover it..
here corn starch is not available, will The glucose Work for it?
I tried potato starch once, it did not work. It became too powdery and just screwed up the print.
However this post renewed my interest in starch experiments. I shall try corn this time. :)
Glucose will not work, as it will get sticky at the temperatures the fuser operates at.
I’m currently experimenting with maltodextrine, which seems to work quite well (although the toner doesn’t stick to the paper well enough yet – may be due to my printer settings).
You can find maltodextrine of 97% purity in sugar-free sweetener powder (of which a large container can be bought for about 80 cents in The Netherlands), with the rest of the powder being aspartame. To get a ‘thin syrup’ like in the mentioned article, dissolve 4-5 tablespoons of this sweetener in 1 tablespoon of water (adding a little bit of alcohol seems to help the stuff to dissolve well). Let it rest until the solution is totally clear (about 10-15 minutes). Make sure your sweetener contains a lot of maltodextrine, (a little bit of aspartame) but no other additives!
This moves the bar to entry a bit lower. Less specialized technology; less reliance of expensive prefabricated materials. Yes it is more work, but we don’t hack because we are lazy. Well not lazy that way. ^_^
I prepare ordinary copy paper with silicone sealant. Use a credit card to smear it on and then off. Wipe with paper towels until no more silicone comes off and paper towel slides easily on the slick surface.(it no longer grabs) Scrub in circles to get every last bit! Let silicone dry. With my printer sometimes the toner does not stick well unless I wipe the the paper with a paper towel dampened with alcohol (I use pure denatured) just before I print. Couple more tips…Sometimes insufficient toner transfers or spots are missing. I drill a couple of holes in the board and poke matching holes in the paper with a needle. That way I can transfer a second layer if the first one is faint. Also Kapton (heatproof) tape is a god-send, but tiny dots of superglue can work in a pinch to stop the paper from sliding around.