Home made PCB's

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
PCB are easy...My experience Post #17
Check my thread. I had very good experience with the product that I'm using on a regular basis. It is really cheap to do your own pcb. I'm doing all kind of very good quality PCB for my own use. I did smd, 2 sides pcb with 0.01" trace resolution without problem, not bad for home made PCB. Have fun.

Bye...

http://www.diyaudio.com/forums/showthread.php?s=&threadid=19585&perpage=15&pagenumber=1

:cop:Edit: Link fixed
dhaen
 
demons_wing, I just saw your thread. What I can say is, that of all the "alternative" methods, the permanent marker method works exceptionally well. The coverage of the copper is very good and it is quickly done, but of course fine lines and dip sockets etc. are not so easy to make. What I find is that all these "alternative" methods are kind of one-time methods for prototypes.

On the other side, the photochemical "standard" method is the most flexible and repeatable IMO. It also gives great results and there's almost no limit what can be done. But it's of course bad that you cant get the boards cheap. Other than that I can recommend this method, I found it works smoothly, I can give some tips if you want.
 
Ok so I would still suggest you to think about the photo method.

Light

There are various UV light sources: sunlight like the guy above reported, uv lamps for plants, fishes and reptiles, mercury gas lamps like for street lighting, factory buildings and outside lighting, face "browners" (sorry for that word) and medical treatment lamps, "daylight" light bulbs. Some experimentation is required here. A good idea would be to look for an old (really old) UV "health lamp" for cheap. They were not too worried about the negative consequences of much UV light for the skin some decades ago. An eye protecting glass were accompanied with it generally.

Foil

Making a good film is the biggest challenge with this method. With some inkjet printers you can print multiple times onto the same sheet and experiment with overhead foils and other transparent foils, transparent paper (for drawing), even normal paper, wetted afterwards with oil or some spray (laquer, hair spray, ...). Paper has the advantage that it distributes the ink better. The film has to be contrast rich and UV light permeable, u get the point. Nice thing is you can reuse the film, and dont have to hassle with a good print plus ironing it to copper.

To expose the board, you fix it onto a glass pane somehow, a broken scanner gives a nice translucent one, with the film and the printed side at the copper.

Agents

NaOH is cheap (pharmacy) and gets dissolved in hand-warm water for 1% strength. That is quite harmless, but dont let it get into your eyes. You develop the board in it. After a few tries you will get the hang. Rinse with water, not spraying, lightly flowing. I etch with FeCl3, very yielding (can be reused many times), cheap, and works at 20°C too (but takes longer). If you have a bath tub, you can do everything in it, gases stay in the tub and can be showered down if you are worried about'em. Let 50°C hot water in for a 2 inch deep nice temperature bath. Etching will be done in a few minutes. Also eventual drops are diluted effectively.

NaOH does not stink. FeCl3 does stink veeeery lightly like acid, but I'm not disturbed by it. Use rubber gloves, the standard ones for the kitchen will do, and a plastic eye protecting glasses (I did'nt, but will buy one). Theoretically NaOH solution can attack glass, but with 1%, nothing happens. Maybe it's even legal to drain it into the sewer, but check first. With standard plastics, PE, PP, PVC, you will be fine. Use not too small an etching/developing basin, so you can move the solution freely while developing/etching, you will also need to move the board free to watch the progress when using FeCl3.

Rinse of course. For drying, I find a hairdryer just perfect. You can use destilled water for everything if you want, but it's absolutely not necessary.

Drilling

I use a dremel-style tool, free hand. Takes some practice but if the copper pads around the holes are not too small, works quite well. Absolute verticalness is not required for most situations. When the holes are already there in the copper, you get some kind of "feel and hear" if you are touching the copper while drilling. I would not spray too much around with laquers and stuff, just let the photoresist on, it's a good shelter and most of them can be soldered.

Also see this post that got me going:
http://www.diyaudio.com/forums/showthread.php?postid=741229#post741229

Somehow I always thought that I can't do that, but with a little bit of passion, so much is possible and really easy ;) :smash: :smash: :smash:

HTH,
Lukas
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.