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Beginner looking for advice

Hello All,

Please excuse the beginner questions; this is my first attempt at etching a PCB.

I bought some 2oz dbl sided boards, and will be etching them using Sodium Persulphate. I've done the traces using press-n-peal blue. I do not yet have an elaborate set up, and I'm looking for any advice your willing to share.

I've read that I should add 1/2lb Sodium Persulphate crystals to 1 gallon of warm water. The board should be submerged until the copper that is not protected is dissolved. Am I missing anything? Any tips or tricks that would be helpful? will this solution be strong enough? How does one dispose of the remaining etching solution?

Lastly the board is a breakout of sorts, taking a db25 and directing the individual wires to terminal connectors. The board will be exposed to short pulses (1-3 seconds) of 24VDC @ up to 5 amps. The traces are

1/16th of an inch thick and separated by only 1/32th of an inch in many places. This board will not be used for transferring signals, just on or off for short durations. Does this sound ok?

Thanks, Brian

Reply to
Cat
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There's no directions on the Na2S2O8? Is it straight from the chemical plant? I use ammonium persulfate. Agitation and heating will speed up the etch. I've preheat my etch in a microwave oven.

About PCB trace capacity.. If the traces glow from the current...that's bad... If the traces burn the epoxy...that's bad..

I've never checked if traces will blow...I've gotten lucky. If a trace blows..then I google for a strip current capacity chart or formula.

D from BC

Reply to
D from BC

Are you a summer intern? It's possible someone is making fun of you.

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20$. I repeat: 20 bucks.

You could have spent the time waiting for the delivery guy reading the datasheet to your connector and figure out if they're rated for 5A per contact, if you're using one contact at a time that is.

Reply to
a7yvm109gf5d1

I searched and found several places one can buy them online, but I thought this would be a good get my feet wet project. I've always been interested in electronics just need the experience.

Reply to
Cat

You're getting experience that there's better experiences in electronics. Make something special.. D from BC

Reply to
D from BC

Those usually go in sci.electronics.basics.

Those question (if advanced) usually go in sci.electronics.cad.

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Mike Harrison's page:

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*-can't-be-bothered-*-*-*+PCBCART+Copperset+*-have-not-tried+Mike.Harrison+welcome.comments+highly.reccommend.them

David L. Jones' 25-page PDF:

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*-universities-*-*-*-*-*-are-*-including-it-as-*-reference-material-*-*-*-*-*-*-*-*-*+zzz-zz+disagree-with-*-*-*-star-grounds+*-major-*-PCB-*-package-*-*-included-it-in-their-Help-system

A quite comprehensive PCB Resources page (link farm).

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*-practices+GNU+Lazar.Rozenblat+DEMOs+guide+Tutorial+tips+design.rules+*-*-calculator-*-*-*-*-*&strip=1

As a7yvm109gf5d1 has noted, there are vendors who have these readily available off the shelf.

-- Several weeks in the lab can save a few hours in the library.

Reply to
JeffM

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