Looking for a good DIY PCB kit - RS ones any good? Others?

[macboy]

In the past, I have had great results with the radio shack stuff. You don't need the kit, but it does come with the essentials: a couple of small PCBs, etchant, and a tray to do the etching.

The simplest DIY PCB is made by applying something ("etch-resist") to the PCB to keep the etchant away from the copper you want to keep, then etching the board. It's really that simple. The etch-resist can be as simple as lines drawn on the board using a "Sharpie" permanent marker (seriously) or rub-on transfers like these ones at Radio shack. I like to use the rub-ons for the IC pads, holes, etc., and just use the sharpie to connect-the-dots. I think that it's obvious that you should finalise the design on paper first, and only then begin laying down the tracks on the PCB.

It is important to make sure that the PCB is really really clean to begin with, so that the etchant can efficiently etch the copper away. Otherwise, etching will take too long and this will result in some of the tracks getting etched, either through the etch-resist, or from underneath it. Clean the board with a new scouring pad and ajax/vim/whatever. It should be shiny with no trace of oxidisation when you are done.

If you want to get fancy and design your board on the computer instead of by hand, then of course you can try some of the print and iron-on methods. I have had success simply printing onto a transparency and then ironing onto the board (high heat but not high enough to melt the transparency!) and just peeling the transparency off. The toner seems to stick to the copper better than to the transparency. The toner is the etch-resist. This was a number of years ago; transparencies these days may have better adhesion to the toner, so they may not work well. You may want to try different brands.

[SY]

Safety Warning!

PCB etchants like ferric chloride can mess you up very badly. Use rubber gloves and safety goggles. Dispose of the waste according to your local regulations for hazardous and toxic materials.

[Kermit]

[QUOTE]Originally posted by soundNERD
[B]DONT use photo paper. it melts in the fuser and they don't make laser photo paper.
[QUOTE]

I have made several dozens of pcb's using photo paper and have never experienced any difficulties with melting. Then agian i guess it depends on the paper.
I have used HP glossy photo paper with some success, it left a thin film over the hole board, that had to be rubbed away with a finger. Same thing with Epson and some other brands I can’t recall.
The best result I have had is using a noname brand available at www.biltema.no (Perhaps not to useful if you don’t live in Norway or Sweden). With this paper I have had absolutely perfect result every time, it’s almost like it was made for the purpose. Now I use this paper exclusively
It looks like this: http://www.biltema.no/Archive/Produc...e/23-771_l.jpg

For etching I usually use natriumperoxidisulfat, (I’m sure someone will arrest me for typing that wrong..) not because it’s that good, but its fairly harmless and easily available.

A last tip: to prevent smudging of the tracks use masking tape to fasten the paper to the pcd while ironing.

[Alcaid]

Anyone who knows a way to transfer a drawing over to a PCB when you only have an inkjet printer?

And to Kermit:
How small traces/distance between traces can you make with the paper from biltema?

[Kermit]

The smallest I have done so far is 0.024 inch. (0,6 mm) Haven’t had the need to do anything smaller.

[SY]

For etching I usually use natriumperoxidisulfat, (I’m sure someone will arrest me for typing that wrong..) not because it’s that good, but its fairly harmless and easily available.

Sodium persulfate in English, also potassium and ammonium persulfates work. They're slower than FeCl3, and they are NOT harmless. These are relatively powerful oxidants, are corrosive, and MUST be handled and disposed of with GREAT CARE.

[Kermit]

Obviously nothing that will etch copper is going to be absolutely harmless, however I believe this stuff is a lot less damaging to people and the environment than ferric chloride. No matter what acids you are working with you should take the appropriate precautions. That said, stupid mistakes tend to happen and I have on one occasion spilt this stuff on my hands without any injuries (other then it was fairly hot). It did leave a red/brownish stain on my clothes though.

[soundNERD]

If you only have an inklet printer, there is 1 simple answer. no matter what you try, no matter how much you swear at it, it isn't going to work. Ink just doesn't stick to copper,

Go to a Kinkos or any copy shop with the pcb and have them copy it onto a thick, glossy paper.

Then Iron it on and etch.

just wondering, what can FC do to you? Thats what I use.

-Mike

[bbksv]

Why not use the photo-etch and transparency method?

[Kelly McDonald]

I highly recommend Ammonium Persulfate over Ferric Chloride. Ferric Cloride stains absolutely everything, and I found that mixing Ammounium Persulfate with very warm water (use in a well ventlited area) and gentle agitation works far better than Ferric Chloride.