Silk Screening PCB's...need help!

[therecordingart]

Ok guys...

I want to transfer my circuit to the copper side of a PCB. I've tried tracing/using resistant ink and also the whole laser print/iron method with less than satisfactory results.

I've made a stompbox (a simple boost) and all of my band buddies and a few clients want one (15 in all).

Where can I get info on how to silkscreen? Is it ideal for running off large amounts of PCB's? Is there any easy method that you advise on?

 

[Sleeper]

I don't know about where you live, but here in LA some of the places that sell screens will also burn them for you if you provide the artwork. A 10 X 20 inch screen is about 35 bucks.

Call your local screenprinting supplier and see if they can do that.
If you want to burn your own, you'll still be better off at a pro supplier than at an art supply store, but that would do in a pinch.

Use enamel ink, a little practice and you'll be set. the boards come out fine.

I kept gettting bad traces with the iron-on/press on kit. It's fast, bit IMO it's not worth the time it takes to troubleshoot the circuits when the boards are dodgy.

Sleeper

 

[gyraf]

for 15 pcs, I think the photo-resist process is still easier and cheaper..

 

[Vetsen]

I was a screen-printer in a former life. I still do it as a hobby. I would recommend not going this route. I have managed to get great results from press n peel / toner transfer paper method. You might also try the photo sensitive boards.

Screen-printing can be cheap, but to do it right, you will end up spending lots of money. The up-side to it is that you will be able to do front panels and even t-shirts. The chemicals are quite expensive. here is a breakdown of the cost in my area.

$50/ gallon photosensitive emulsion (to make the stencil)
$20/ gallon stencil remover (to reclaim screens for future designs)
$20/ screen (aprox 20"x16")
$50/ quart of ink (Nazdar GV series), $50/gallon for textile ink
$20/ scoop coater (to apply the emulsion to screen)
$20-$25 squeegee
$30-$1500 for a light source to develop the image into the screen
$20-$40 for jiffy clamps (DIY screen press)


These figures are from memory, you can find kits on ebay for $400.

here are some links

http://www.screenweb.com/
http://www.americanapparel.net/
http://screenprinters.net/
http://www.screenprinters.net/articles/
http://www.ryanrss.com/
http://www.ranar.com/

I am not trying to discourage you, I just want you to know that screen-printing itself is an art. And it can be so much fun too.

Here is my method for toner transfer PCB making.

I use TT paper from Pulsar.gs $14 for 10-12 sheets
Modified heat laminator from GBC (H200) $100
DIY etch tank made from Plexiglas and fish-tank parts $25

Pulsar has a whole site dedicated to toner transfer PCB making. They will even help you troubleshoot your problems.

http://pulsar.gs/1_PCB/a_Pages/1_Menu/Overview.html

Look into the toner image aplicator (TIA) it's a modified laminator instead of using a hand iron. It made a huge difference for me. I get almost perfect results now.

If you want more details on screen-printing let me know.

Here is a DIY silk-screen frontpanel of my 1272 mic pre.

Vetsen

 

[gyraf]

Thanks, Vetsen - very good info.. :thumb:

 

[maneco]

and don´t forget this page :grin: :thumb:

http://www.pablin.com.ar/electron/trucos/placaci/index.htm

It works!!

 

[Vetsen]

[quote author="maneco"]and don't forget this page :grin: :thumb:

http://www.pablin.com.ar/electron/trucos/placaci/index.htm

It works!![/quote]

This is basicity the same method as the Toner Transfer (TT) paper from Pulsar. It works quite well for me.

I visited pulsar.gs the other day and found that they have a new recommendation for the laminator for half the price ($50 USD.

Ever since I bought my laminator for DIY PCBs I have had really good results. I will say it again, if you are having problems with Press n peel or regular toner transfer paper, give this a shot. It really works well.

Vetsen

 

[Guest]

silksreening is easy / speed ball makes a diazo kit for

25 $(us) includes silk juice and sensitizer

using sythetic silk (18-25$ us per yard)

use some medium duty canvas stretchers (x4) 12 bucks .

bondo spreaders 3$

#1 (250 watt) photo flood from photo suply store 7$

the rest is priceless :grin:

 

[Guest]

 

[Guest]

:wink:

 

[Guest]

 

[Guest]

 

[Guest]

 

[Ptownkid]

how much does one kit of photoresist do? 1 screen?

 

[Guest]

you can probably get about 4, 20x20 screens if not more

depending how non-sloppy one is.

after mixed , the stuff keeps in the refridgerator for months so you can use it later.

 

[Guest]

plus you can also do the silkscreen legend after you make the boards

hope this all helped ,


driller45