best materials for pcb making using laser printer method

[grom]

hi,
i've been trying out the laser printer and i'm not able to get the proper kind of glossy paper. the toner comes off with the paper when i soak it in water and peel it. is there a nearly perfect kind of cheap glossy paper that can be used? and is there any particular way that i should heat the paper on the pcb with the clothes iron? and should i use hot ferric chloride for etching?

 

[LTX71CM]

Sounds like you're not getting it hot enough.

I use (free) paper from magazines for my occasional rush board needs. If you live with a female look for a fashion or decoration magazine as they tend to heave thicker and higher quality paper, also save yourself a tongue lashing and only use a page that's ads on both sides. Catalog pages work somewhat but the paper is often too thin to get through a LASER printer after being heated, it curls.

To apply the print to a CLEAN PCB blank, first align it and then with a maxed out iron run over the print several times, press firmly a few times, get it hot. Let the board cool and place it in a sink of water and let it soak. Slowly peel away the paper as it loosens up.

You can etch with room temperature Ferric Chloride but the process will go faster if you heat the etchant. Generally chemical reactions are accelerated with heat. DO NOT heat the Ferric Chloride in a microwave, your family toaster oven, an oven or anything that will ever see food again. Take no chances.

 

[eptheta]

I have made several PCBs using toner transfer, but I used Kodak photopaper.
I re-use the leftover paper, so it isn't all that costly, comes out to 0.2$ per page....

Same process:
-Laser print/photocopy onto the photo-paper
-Iron it until the copper gets so hot you can't touch it
-Immediately dump it in water.
-I usually peel it off immediately, but this leaves a lot of paper stuck between the finer parallel toner lines.

For etching, I do it in a glass dish in a well ventilated kitchen.
With a new packet of FeCl2 there's no real need to heat it since the reaction is exothermic itself when you add water, but if you are re-using some old etching solution, then there is no harm heating it a bit...

I avoid heating it too much (say, till it boils) because that usually melts the toner a bit making the traces thin and unreliable. But it is a fact: the reaction is faster at higher temperatures.

 

[(*steve*)]

Cleaning the board before applying the paper is key to getting the toner to bind to it.

When the toner binds properly, it is actually *really* hard to shift it.

Clean the copper with something mildly abrasive (say an abrasive pad used for cleaning dishes -- the green ones). And work with gloves so you don't get oil from your hands on the board.

 

[grom]

thank you everyone for your quick replies!
i'll try out what you've said please post more tips if you have any

 

[alfa88]

I use HP presentation paper. It's slightly glossy and I've had very good results. There is a post on Instructables on making etchant from hydrochloric acid and peroxide ( Stop Using Ferric Chloride). The advantage being that it is reusable and cheaper. I couldn't find the proper acid strength at the hardware store so my etching experiment failed.

 

[(*steve*)]

Ammonium persulphate is another option.

The HCl plus peroxide is a good option if you're going to be doing many boards over a long period of time, but otherwise it requires a bit of maintenance.

I have used an inkjet paper with a plastic coating. (After verifying that the plastic coating doesn't melt in the laser printer of course!)

The plastic coating sticks to the board a little, but it sticks very strongly to the toner.

The problem with toner is that it is not completely impermeable to the etchant, so the tops of the tracks can be etched. The plastic coating fixes that at the expense of making it quite a lot harder to get the paper off the board. The risk is also that a little plastic not removed will leave coper bridges on your board.

However, it's easier to remove bridges than repair tracks.

I've found that it doesn't matter a great deal of your tracks look like they're covered with paper fibres as they will absorb the etchant and it will get through and you will still get a clean edge to the tracks.

I use an old electric toothbrush to clean up the board prior to etching.

 

[grom]

wow! THIS is a forum! : thanks ppl!