Hi

Okay...someone mentioned this on another forum, but I haven't heard of it being done.

I, like many have, am struggling with the laser printer toner transfer method for making PCBs myself. It never quite comes out perfect...almost...but never all the way, especially with those tiny traces.

I want to try something...rather than transfer the toner to paper, then try to iron it off the paper to a PCB, why not just try to find a way to trick a laser printer into accepting a PCB (I might have to widen the roller area to fit the height of standard FR-4 board in there), and have it print directly to the PCB. I'm thinking I would likely have to use an iron, laminator, or other heat source outside the printer, since most fusers require the paper to roll around in them, and FR-4 won't roll too well.

So, does anybody know if toner will stick (even moderately well) to copper board? Would I have to transfer charge from the printer to the board somehow (I thought the paper somehow got a charge to make the toner stick)? Maybe using metal brushes?

I was thinking of tricking the printer into thinking its fuser was warmed up, but then I though "wait...the PCBs not going to go through it anyway", so I can just let it heat up. I guess what I need is a recommendation of a printer I can easily modify to accept a flat sheet, maybe by cutting a hole in the back.


Thanks for the help!

-Dewey

 

People have modified laser printers to print directly on PCB stock. Some laser printers even have doors in the rear that you can open to provide a straight through path.

There is a toner transfer paper sold by DigiKey, and Mouser called PulsarProFx. it is a stiff almost cardboard like paper coated with a starch that will accept the toner when dry. When wet the starch turns slimy and the paper lifts from the PCB without any action on your part.

The paper is sold in packs of 10 sheets for $10 or $15 but it goes a long ways because you cut off and use what you need to cover the board. Cost is under 5 cents per square inch.

Visit the http://PulsarProFx.com website for detailed instructions. There are examples of what the process can do on their site. I suggest a laminator because it provides more uniform heat.

Disclaimer: Some people are happy with paper not intended for PCB work. Other like P&P Blue. Some do a good, maybe great, job with a thrift store iron. To each his own.

EDIT: There are also some inks that stand up to etching. People are using this ink with inkjets to directly print on the PCB stock.

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Transfer to paper is an electrostatic process. Copper will probably mess this up.

Copper or the fiberglass underneath it will probably scratch your $100 drum.

 

That will soon kill the printer/drum.

I know we need one more how to make a PCB with a laser printer and glossy paper..

Clean the copper better (remove oxy and wipe with alcohol; keep finger oils off of the copper), press the heat on the board for 20-30 seconds before moving the iron at all, apply longer heat in the transfer, let the board cool before you soak it. Drop it in warm water and let it soak for a bit (no rushing here either), then rub the paper and gloss off with your thumbs.

Took me forever to get it right (I do not have to touch it up with a sharpie or start over). If you rush it, it will look bad. Also, I put a folded paper towel over the PCB/paper and iron through it not right on the paper.

 

That seems to be the consensus. A few years back there were several sites on the web that made the mod. These days most people are moding inkjet printers to do direct resist printing.

As I said in the disclaimer. People are free to use whatever they please. We have been down this road many times.

For my money Pulsar is the easiest to use and gives the best results. Transfer is 100%, the transfer is a good as you laser printer can print. The others I have tried either do not release as well or are to slippery too hold the toner. Pulsar has neither of these problems.

Some (many) people get good results with other material. But we see a lot of posts from people who do not.

What is good enough depends on the type of board you are making. If you are working with fine lines Pulsar is the next best thing to photographic.

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Please post questions to the forums. PM's are for personal communication.

BCHS/3v0's Tutorials
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