Hi, I made a tutorial about how to make PCBs with UV light, I thought it might interest you all. Here's the URL: http://members.lycos.nl/anthonyvh/index.php?page=pcb
Nice tutorial (though your navigation system confused me, had to scroll down a screen to find anything). One point with either a new lightbox or new board supply, doing a test strip will give you the best results with minimum wastage. Produce a transparency with straight black lines running along it in a range of widths to represent tracks, set it up against the pcb, then cover with black paper or card except for the last 1/2" (10mm). Expose for 30 secs, move the card along 10mm, expose another 30 secs, and so on, so your board has had a range of exposures from 30 secs up to a few minutes. Then develop as usual and pick the best.
Thanks! What's with the navigation? What resolution is your screen set too? I'll add the info. Do you want me to mention your name?
Yes, transparencies give the best result. And you don't need an expensive laser printer & special iron on paper for it! Chips are made with UV light, not with an iron on method . That has to mean something .
If done properly, you should get better results than with the laser printer method. In my experience the UV light method is more reliable and more accurate, and allows you to produce thinner lines (tracks). Small electronics companies around here use the UV method to make the PCBs for their products. (On a slightly larger scale of course) At some stage this summer I intend to publish my own 'how to' explaining how to make a proper UV ight box which is nearly as good as the professional ones, using an old flatbed scanner and parts from a scrapped caravan tube light.
It's Firefox/Mozilla reacting to some non-standards-compliant coding, the Tutorial start has got pushed below the menu bottom instead of at the side of it. Renders OK in IE. Naah, test strips are a basic technique in proper photography.
Just a side note regarding printing on overhead transparencies on a laser printer...laser printers are considerably hot inside, which normally causes the transparency to melt and subsequently jam inside the printer. I'd recommend printing onto paper and then photocopying it onto a transparency if all you have is a laser printer. -Sam
So everybody is getting good results with transparencies printed in a laser printer then? I was/am worried that the printed lines wouldn't be solid enough to block all the UV light. Also, have you tried going down to 0.005" traces with your setup? I am using another guide to build a UV exposure setup that uses a geometric collimator to produce lines as small as 0.005" accurately. Here's the link to the guide that I was following.
Standard OHP film passing through the printer once will not be good enough to draw very very thin tracks. If I'm using OHP film, I send the sheet through the printer 2 or maybe 3 times to get it solid enough, otherwise it will pass UV light through and ruin thin lines - though the thicker lines are unaffected. If do multiple passes of the OHP film through the printer, the thinnest line that Proteus can draw can be reproduced on the PCB. I got better results using the (expensive) film designed for PCB artwork, and only needed to go though the printer once. Thick (100gsm+) tracing paper also works just as well, and is slightly cheaper.
Seriously, I think you should try using standard stuff first. I've used nothing but standard inkjet transparencies and every time I succeeded in making the PCB (except when I did some experimenting with a certain developper...). If the lines aren't solid enough use 2 transparencies and tape them together. I used to do this, but I don't think I will do that anymore. Read more below . Take a look at the last photo of the tutorial & the text that goes with it. There's a 0.005" line going between 2 SOIC pads on the PCB. I made it with only one transparency. That why I'm going to use only one transparency from now on. I didn't use any fancy lenses or whatever that collimator may be either .
Devil H@ck: I note you're using an Inkjet printer, so your results will vary from using a laser printer. The pylon: This is the sort of stuff I have used and had good results with: http://www.rapidelectronics.co.uk/r...CAT_CODE=30342&STK_PROD_CODE=M29485&XPAGENO=1
