why do you need to use a laser printer if you want to print out PCB for etching?
can you do it with a ink jet printer and isn't it dangerous to use photo paper on a laser printer?

thanks in advance

Thomas

 

When you're etching, you need a resist for the acid. The laser printer puts down a heavy layer of toner, which gets transferred to the PCB (if there is an adequate coating on the paper). With an inkjet, the ink doesn't get fused to the paper. And, I believe, the ink would get dissolved rather easily in the acid.

Laser printers are cheap these days anyways, not like many years ago. Definitely a good investment for cheap printing at home and the occasional PCB. Personally, I get all of my PCBs done professionally, etching at home is a thing of the past for me. If you're a student, you can get 33$ 2-layer PCBs from www.4pcb.com .

Steve

 

And, I believe, the ink would get dissolved rather easily in the acid.

Steve is right, as usual. Most inkjet inks are water-soluble. If you still want to do your own boards for the bragging rights, try a thrift store, Craig's List, or Freecycle for a used laser printer.

 

InkJet, when you look close have very small holes in the print which give breaks in tracks especialy in fine art work. As stated before laser printers put down thicker layers of ink.

 

http://computer.howstuffworks.com/laser-printer3.htm

Laser printer toner is basically a thermoplastic and it melts and fuses to the paper. You want to melt it together but not adhere permanently to the paper so you can transfer it to the copper to cover it so it does not dissolve. The copper dissolves with direct contact to the chloric ferrite aqueous solution. If you leave a board in the solution long enough all the copper, even the copper under the mask will dissolve. All you are basically doing is a controlled dissolving of copper. Injet has many problems and one of them is it will dissolve in the aqueous solution and the surface tension of the copper makes it difficult to wetout. If you do this yourself you have about 4 methods.

1. using a router and an end mill, mill off unwanted copper - difficult and messy.
2. Purchase a presensitized board, copper to tranparency film , activate under UV light, rinse with acetone.
3. Laser print onto a paper that will allow the trace to release without destroying the laser printer, Use a silicone film to transfer heat from iron to board. The silicone can handle the heat and gets filmwetout, disolve paper backing in water, lightly scrub off.
4. Buy rub on stencils to make your trace.

 

If you are able to print directly to a PCB with an inkjet, you can heat the board and "fix" some of the inks to make them sufficiently resistant to water to work. There is a Yahoo group - Homebrew PCB - where that method is frequently discussed.

The other problem with inkjets, unless you print directly on the PCB, is that you cannot transfer the images nearly as easily. Since they go on wet, they tend to absorb into the paper or other medium.

John

 

Etching is the process of using strong acid to cut into the unprotected parts of a metal surface to create a design in intaglio in the metal (the original process—in modern manufacturing other chemicals may be used on other types of material). As an intaglio method of printmaking it is, along with engraving, the most important technique for old master prints, and remains widely used today.