making PCB's

[1878]

Hello Everyone.

I've only ever built anything on perfboard. I'd like to build a Zombie Chorus next, so I thought this might be a good time to start building my own PCB's. What are the method's that have worked best for you ?? I know I'm gonna make a few mistakes, but that's ok. What's the best board, paper, chemicals or anything else you've found to make your life a little easier ??

As I said, I've never made my own PCB's, so as much info as possible please. Even if you think it's the simplest and easiest thing ever, put it down 'cos I probably wont know it !?!?

Thanks everyone.

I've got access to a laser printer via work, as well as the various tools for cutting, drilling etc...

[arma61]

HI

just a start

http://www.geocities.com/jf_moreira/pcb_en.html

then you can search with Yahoo -> "make your own pcb", hundreds of results.

Cheers
Armando

[kupervaser]

I always etch my pcb's.

Just print the layout on the inkjet photopaper and transfer the toner with the iron, it's called toner transfer method. If you google on toner transfer you can find lots of info on it.

I use the folowwing paper: Epson S041126
I don't know how well this paper is awailable in your country. The awailability in The Netherlands is very good.

THis paper works 100%, i never have to correct my pcb's.

Than etch it with Ammoniumpersulfaat and done.

[brett]

Hi
Press-n-peel is very good too.
I print (laser or inkjet) a pcb outline (say, from Tonepad) to a sheet of paper.
Then either (i) stick PnP over the top of the image and laser print (the sheet with PnP on it) again, or (ii) photocopy the image, stick Pnp over the copy and photocopy again, using the sheet with PnP.

Some tips:
Use "invisible" tape, because it stands the rigours of photocopiers and laser printers.
Cover the leading edge of the PnP with take, to help prevent a paper jam.
If using a photocopier, set the brightness to a little darker than average.

Before ironing on, give the copper side of the PCB a rub with sand paper or steel wool.  Make sure that the edges aren't burred, or the iron won't sit flat on it.  Finish with a rub with tooth paste (maybe I just like the smell, but *maybe* tooth paste has oils in it that helps the transfer process).

Buy some spare blank PCB and try different iron settings, etc.  Don't worry if it doesn't work at first.  You'll get skilled soon enough.  Try transfering some 0.02 inch lines that are 0.02 inch apart.  Then 0.01 inch lines.  Once you've got that you're set.

PS Ferric chloride is also a good etchant.  Most etchants can be diluted for slower action, heated for faster action or diluted AND heated for economy and not too slow (gotta love that). e.g. 1 part ferric cholride, one part water heated to 50 Celcius (120F).

Have fun.  PCBs are fast to populate once you've made it, and usually organised and prevent lots of bugs that less structured systems have.
cheers

[WLS]

First I print the template from a laser jet printer inkjets won't work onto projection film and then place the film over the positive photoresist copper clad board that I cut to size using dremel's diamond saw blade made for cutting ceramic tile. The blade is thin and creates very little waste or damage to the board. This board does not require cleaning it comes from the factory in a ready to use state.

I place the template over the board toner side down and photo-resist side up . Then secure the template to the board placing a piece of glass over the top of the template.

Turn on a UV light. I use a standard florescent black light that you can pick up any where. After the light has been on for the correct amount of time which varies from light to light due to inches above the work piece and intensity of the light longer is better. I get a nice detailed image with 20 minuets under the light.

You then shut off the light and place the board into the developer solution and wait about forty five seconds you will see the photo-resist starting to lift off the board. Use a sponge brush to wipe the photo-resist off the board leaving only the traces!. Then immediately submerse the board into water this will naturalize the developer.

Then the board is ready for etching. I use Ammonium Persulphate it costs about  ½ as much as the Ferric Chloride and since I have a large tank that requires a gallon of acid well... Anyways it only takes me about 6 minutes in the acid before again placing the piece into water to naturalize the acid.

All the chemicals I use are made from MG Chemicals along with the board.

1.   #418 Positive Developer
2.   #410 Ammonium Persulphate
3.   #600 Copper Clad Boards Presensitized with positive photo-resist

The whole process ready to drill in less than a half of an hour.

Be sure to wear rubber gloves when handling any chemicals used for etching!   

Bill

[MikeH]

The photo essay at tonepad is where I learned.  If you follow it closey you have a very good chance at getting very good results on your first try.

Here' one thing that I learned though (if you're using press n peel):

You have to preheat the board to get a good etch.  This makes the pnp cling to the board right away.  BUT- it's not good enough to just lay your piece of pnp on the preheated board, because I've found it wont stick completely, then when you put down the iron it shifts, and you end up with this sort of 'ghost image' of your layout on your board.  Not good.  What I do to prevent this is preheat the board, then I line up my pnp and stick it to the board, but then I roll it out a few times with something cylindrical, like a ball point pen.  This makes it stick more thoroughly and keeps it from shifting.

Oh and muriatic knocks the socks off Ferric Chloride.  -Ok, so that's an opinion, but I've used both and muriatic is cheaper, faster, and less finicky than FeCl.

[Ice-9]

Of course the big advantage of using Uv over the press n peel or print and iron on methods are that once you have printed your pcb on the clear paper it can be used over and over again, wheras the iron on way you have to pribnt a sheet for every pcb. But then again you may only want to make 1 pcb of the same type.

[Dan N]

I a method very similar to WLS. I do use an inkjet printer for my transparencies and have never had a problem.

This is the board I use:

http://www.circuitspecialists.com/level.itml/icOid/3802

I've only used the fiberglass substrate although the price of the phenolic is very tempting.

Anyway, print out a transparency, peel off the film on the board that protects the emulsion, align transparency on the board, weigh down and flatten with a piece of glass, then expose with a regular florescent light (3 to 4 inches above the board) for about 10 minutes. A quick bath in this chemical:

http://www.circuitspecialists.com/prod.itml/icOid/6014

and etch with whatever you please.

[biggy boy]

I use the laser printer on inkjet photopaper method.
I find it an economical method, that is of course if you have a laser printer.
One word of caution Don't get caught using the wife's iron

Glen