Homebrew Circuit Boards: Methods? Supplies?

[Roger Merchberger]

Rumor has it that Jeff Walther may have mentioned these words:
>I imagine this topic has come up before, so my apologies in advance.
>
>Do folks have a recommendation for suppliers of circuit board making 
>materials, or a good source of such information?

I got my stuff at http://www.circuitspecialists.com/

Best prices & selection I could find and they have 1/16", 1/32" and 1/64" 
thickness pre-sensitized photoresist boards. They even have "how-to" books 
for beginners on making photoresist boards & whatnot.

http://www.circuitspecialists.com/prod.itml/icOid/7783  (Link to the 
beginners book I mentioned - I bought it and it's a very good read.)

I have not yet had time to build the projects for which I purchased my 
shiznit, but I should be able to before Xmas, so I'll know a lot more 
soon... ;-)

I am not affiliated with the company other than being a (so far) satisfied 
customer.

>In fact, I have not been able to find precoated board (photoresist coated) 
>in the .050" thickness.  So I will either need to use a liquid photoresist 
>or try a toner transfer system.

I dunno about 0.050", but would the 1/32" thickness be close enough? 
(That's 0.03125" thickness, if you can believe the Winders calcaputer 
applet ;-)

>That raises other questions.  Are the Toner Transfer Systems reliable

No. Especially since the toner xfer systems were designed around toner that 
melts around 300 deg. C... a lot of the 'microfine' toner printers melt 
their toner a *lot* hotter than that, and don't get good adhesion to the 
xfer sheets. (Most laser printers made in the last 5-8 years are all 
microfine toner - anything 600dpi+ will be.) The last time I tried (5+ 
years ago) I used 10 sheets to *finally* get one that didn't require metric 
buttloads of touchups with a resist pen.

>If the TTS is not servicable, then I'll try the liquid photoresist.

I'd say to try pre-sensitized... but that's just me.

>  Would it be better to simply spray on, or should I try to rig a spinner?
>
>Do the developer and/or stripper usually turn out to be some commonly 
>(cheaply) available chemical?  I would prefer to avoid paying $6+ for a 
>small bottle if I can avoid it.

One kg of ammonium persulfate will make 4 liters of etchant, and it's 
around $18 USD (not including shipping) - not sure if you'll be able to 
find it much cheaper than that, but if you do, let everyone here know! ;-)

The other chemical used is ferric chloride.

Hope that helps,
Roger "Merch" Merchberger

--
Roger "Merch" Merchberger   | A new truth in advertising slogan
SysAdmin, Iceberg Computers | for MicroSoft: "We're not the oxy...
zmerch at 30below.com          |                         ...in oxymoron!"