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3 Traces between pads ?

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Those 5mil lines on the 20mil grid don't look very good to me.
 
Shax said:
Alignment aint the issue, neither is getting a decent layout... The PnP blue film seems to be extremely prone to leaving pits or missing areas on tracks. I clean the boards with wire wool, followed by a pcb cleaner block, and finally a good ole degrease with IPA and acetone (pure, not nail polish remover!!) mixed 50:50....

Maybe Evan can help you with that, he has more experience with PnP.

Your problem may be with the toner cartridge itself. For best results buy a new one and use it only for PCBs till your other one goes dry. For best results use a laminator instead of an iron.

With the Pulsar system you apply one or two layers of green TRF (toner reactive foil) to the toner prior to etching. This extra step helps prevent the type of problems you are having. It is easy to spot toner with no foil or spots with no toner. These can be hit with a sharpie and a second layer of TRF applied. With a reasonable toner cartridge fixups are the exception. Most boards do not need it.
 
Shax said:
Alignment aint the issue, neither is getting a decent layout... The PnP blue film seems to be extremely prone to leaving pits or missing areas on tracks. I clean the boards with wire wool, followed by a pcb cleaner block, and finally a good ole degrease with IPA and acetone (pure, not nail polish remover!!) mixed 50:50....

I can assure you that alignment, most certainly, IS an issue. Getting the top and bottom artwork so they are within 5 mils or so is important. It's not hard but still pretty important.

cleaning with steel wool - that could well be your problem. Everything I've read says not to use steel wool. I use wet-or-dry 600 grit paper and acetone to degrease. Never had a problem.
 
Steel wool usually contains anti-corrosive treatment, which might be oily.

On the other hand, "SOS" pads contain a good degreasing soap and I've had good results. Rinse throughly.

Has anyone tried quickly dipping the bare board into etchant to verify it's really clean? Then rinse, dry and transfer the toner...
 
Shax said:
Alignment aint the issue, neither is getting a decent layout... The PnP blue film seems to be extremely prone to leaving pits or missing areas on tracks. I clean the boards with wire wool, followed by a pcb cleaner block, and finally a good ole degrease with IPA and acetone (pure, not nail polish remover!!) mixed 50:50....
I am still surprised that people have this experience, I really don't know what the secret is. Seriously, I put very little effort in when I make my boards. I scour with scotch-brite until the board is uniformly clean, then wipe with isopropyl on a paper towel, and iron away. I'm NOT very careful and consistent while ironing, and yet my boards always come out great. I pretty much never get any pitting or broken traces, even though I'm using a cheap no-brand refilled toner cartridge in my printer that does tend to leave small pinholes on the printout. I've even used various iron temperatures and never noticed tremendous differences.

I guess I'd still just recommend trying the dowel method and playing with your iron temperature just to be on the safe side, even though I didn't have troubles even when I was just ironing on a flat surface. Once again, there's a tutorial on my website detailing the method that I use, if you run out of ideas perhaps you can try to duplicate it and see if it works out any better.

The only other variable I can think of is what 3v0 mentioned, and it's an important one: toner. The toner is what has to stick to the board and so the toner in use makes a tremendous difference in how good your adhesion is. If your toner really doesn't want to adhere to the board, it's not going to matter what transfer film/paper you use. If you're getting a lot of lifted traces and pits, perhaps you should try a higher iron temp to make sure your toner is melting completely. Unfortunately, of course, toner is the most expensive and difficult thing to "experiment" with because toner cartridges aren't cheap and you usually don't have many choices about brand or quality.
 
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I use Dawn and a green scotchbrite pad.

It is not hard to get the board clean, not touching the surface once clean is. At times I have used nitrile gloves. Maybe overkill if you wash you hands well to start with.

Be sure you are not blaming the cleaning process when the problem is elsewhere.

I am a big fan of using a laminator. It takes most of the guesswork out of the process and is repeatable.
 
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