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[on:]

I want to make some shields, but i dont have a laser printer so toner method is out if the question. PCB fabrication seems quite expensive in the uk so i was thinking about making a UV lightbox out of some uv leds and an old scanner,

anyone else have any suggestions or tips

[Reply #1 on:]

I was wondering the same thing.  (except I'm in the us)

[Reply #2 on:]

There was a suggestion on some thread on the forum last week about heading to the local copy shop to have the laser-printing done.

I guess it depends on your time value. I had two boards made by BatchPCB. Less than $40 for both of them. Worked first time. (They actually sent 4 boards).

It would have cost me more than that, and a lot of frustration, to make the boards myself.

[Reply #3 on:]

i read that topic, i dont have an copy shops near me,

thinking a stripboard would be so much easier,

does anyone know of a program (mac or windows, ideally mac) that can convert schematics to stripboard that would be great

i did a google but there seems to be nothing

[Reply #4 on:]

Ink jet onto transparency film used in combination with photo-sensitized copper clad?

[Reply #5 on:]

Sunlight or a fluorescent "Black Light" bulb is a lot easier and cheaper than building something out of UV LEDs...

[Reply #6 on:]

westfw, do you happen to know how long you have to expose the pcb for, i want to try this out.

[Reply #7 on:]

I build an Uv exposure box out of an old scanner i got for free, and one of those small facial solariums with 4 small UV tubes in it, i found for next to nothing in a flea market.

I used some photosensitive spray called Positiv 20 to make my own photosensitive PCB's.

But getting everything right is a freaking nightmare.  The coat of spray has to be right, the exposure time, the development too.

I usually have it working, but about 1 in 6-7 times i screw up someting :-)

My entire analog synth is made from boards made that way.

But for small simple boards i prefer to use the laserprinter toner transfer, it's just so much easier, but requires access to a laser printer of course.

[Reply #8 on:]

what is the main reason for a Laser Printer anyway? I always thought it was the sharpness of the traces, but then again, if you can inkjet it and then simply copy there must be something else... is it the 'toner' that makes the lines?

[Reply #9 on:]

Toner is nothing but very small beads of polyester.  Normally the fuser in the laser printer heats those beads until the melt and fuses them onto the paper.  When you print on the special transfer paper, that layer of polyester does not bond with the paper is able to be transferred to the board and acts as the etch resist.  (If I understand the process correctly)

[Reply #10 on:]

The "special paper" has a coating.  The toner bonds to the coating (else it would make a huge mess out of your printer), but the toner+coating releases easily from the backing material after you re-heat the toner and stick it to the copper.

-j

[Reply #11 on:]

I hate dealing with etchant and photo developing chemicals, so I'm about to try BatchPCB.  It's more expensive than doing it yourself (maybe), but they also do plated-through holes and vias, solder mask and silkscreens on both sides of the PCB as standard features.

[Reply #12 on:]

I believe the cheapest and easyest method is using toner transfer.

How does it work? Basicly you make the toner replace uv-sensetive coating (used in "photo" method). All you need is laser printer, hot iron (or better, a laminator) and a sheet of paper (but not ordinary white, it doesn't "work". You should use something smooth. The best thing is to use paper from commercials (spam) that you get to your mailbox).

Regards,

[Reply #13 on:]

The best thing is to use paper from commercials (spam) that you get to your mailbox).

The best thing to use is Press-n-Peel Blue, which is designed for the purpose, but costs about US$2 for an 8.5"x11" sheet.

-j

[Reply #14 on:]

Well, that's for you. I define "best" as price/efect  
And I believe, there's no paper that would perform better as "spam" paper. With it, I have done all kinds of complicated circuits, with no problems or whatsoever...

Regards