woo! my first circuit board

timmeh87 · Post by **timmeh87** » Tue Nov 29, 2005 10:46 pm

actually its my third... i screwed up the first two majorly.

and im not saying this one is perfect

but its "workable"

https://muss.cis.mcmaster.ca/~bernast/i ... bottom.JPG
https://muss.cis.mcmaster.ca/~bernast/img/pcb%20top.JPG

:D:D

Metroid fan · Post by **Metroid fan** » Tue Nov 29, 2005 10:47 pm

How did you do that?

timmeh87 · Post by **timmeh87** » Tue Nov 29, 2005 10:51 pm

i used the photoresist technique.

1) design a circuit baord in the free design program Eagle (www.cadsoft.de)
2) print it out onto overhead transparencies
3) get a photosensitive slab of copper plated circuit baord from your local electronics store. while youre there get some developer and some ferric chloride.
4) expose the board to ultraviolet light (flourescent will do) using the overhead as a mask
5) develop the board. all the areas of photoresist that were exposed to ultraviolet light will dissolve away
6) put it in ferric chloride. it will eat away the bare copper, but will not react with the undeveloped photoresist

done!

then touch it up with a razor blade because it didnt develop perfectly...

Post by **marshallh** » Tue Nov 29, 2005 11:05 pm

Ah you used transparencies

I print out my patterns onto plain paper with a laser printer. The toner is ironed on and sticks, while the rest of the paper dissolves. it's not quite as accurate but it is cheap..

Now just gotta find a good system for hole drilling.
Man I wish I could use a PCB fabbing shop.

loup · Post by **loup** » Wed Nov 30, 2005 12:53 am

marshallh wrote:Now just gotta find a good system for hole drilling.
Man I wish I could use a PCB fabbing shop.

I would have to say a drill press comes in real handy

timmeh87 · Post by **timmeh87** » Wed Nov 30, 2005 6:33 am

the first time i tried the "photocopier and a sharpie" method, but the guy who was showing me how to do it (and basically doing it for me) didnt bother to line the two halves up for some reason. : \

theres actually a fab shop at school that im probably going to use mostly... since its free. but i wanted to try it myself. that and the shop just CNC's the boards... which is sort of really annoying. but they drill holes!

bioniclebert · Post by **bioniclebert** » Wed Nov 30, 2005 11:06 am

cool, what are you going to use it for?

timmeh87 · Post by **timmeh87** » Wed Nov 30, 2005 11:49 am

its mostly a general interface board for the PIC16F877A. right now me and a guy on the solar car team are goign to use it to measure the capacity of batteries (with a specialized program of course...)

nos_slived · Post by **nos_slived** » Thu Dec 01, 2005 11:54 pm

I use the iron on method, and once you get used to it, it is easy and pretty effective. It is also cheap, which is what I like.