etchant help

[Zedmin_fx]

Ok I cannot find etchant any where,what else can I use? I have two bords ready to etch, very upseting lol.

[soulsonic]

Do you have a local Radio Shack? They sell Ferric Chloride there.

[Zedmin_fx]

I do a  year ago they had it but when I went and looked for I didnt see it.  I also looked on thier websit and the have it but in stores only, so I put in my zip and they found no stores with it around here. It suks

[Paul Perry (Frostwave)]

You can use a mixture of hydrogen peroxide (readily available from chemists & hair dressing supply shops) abnd hydrochloric acid (also called muriatic acid or spirits of salts, from hardware stores).
Details have been given on this site (search for peroxide).
Or, here is someone's advice on the web - I can't confirm it:

" I've been using muriatic acid (hydrochloric acid 31.45%, 20°Baume, 68.55% distilled water) mixed with hydrogen peroxide (3% solution, 97% distilled water). If your concentrations are higher, you should carefully dilute them before mixing. If you fail to dilute them, your chemical reaction may be quite violent when you immerse the circuit board, resulting in large amounts of heat and dangerous fumes.

You do have to use a plastic basin, wear rubber gloves, and do this outside with good ventilation, as you don't want to breathe any of the fumes. Even though I do this outside, I use a large-diameter fan on a low speed setting to ensure a constant flow of air to carry the fumes away.

I use roughly 2 parts of the hydrogen peroxide solution to 1 part of the muriatic acid solution.
Pour the hydrogen peroxide solution into the plastic basin, then slowly add the muriatic acid solution while gently stirring, being careful to not splash it.

Using a paper towel or rag to wipe the board during the etching process speeds it up a great deal. Wipe, turn over, repeat until fully etched. If you manage to splash the solution on anything, immediately flush it using plenty of water (I keep the garden hose handy.) As soon as the board is sufficiently etched, flush with plenty of fresh water. It's far faster, and much cheaper.

Don't try to save used etchant. If you put it in a sealed container, it will continue to produce heat and gas from the chemical reaction of dissolving the copper, possibly causing the container to burst forcefully."

The only thing I would add, is that peroxide comes in various strengths, from 3% to 20%. Go with the low.

[Zedmin_fx]

Ok I might try that my brother has some etchant some where the only problem is he has to find it ha ha.

[John Lyons]

You can reuse the h202/Hcl solution.
Search for "reuseable etchant" here.
It's a bit slower the second time but worth the effort not to throw it into the water supply!

John

[Zedmin_fx]

Hey I have a bottle of hydrogen peroxide the kind ya get for cuts its 3% will that woork? And also I have 30 ml of hydrocloric acid so my ratios would be 60 ml peroxide and 30 ml of acid. will that be enuph fow two board they are the ousb and the fuzz factory.

[merc]

Don't try to save used etchant. If you put it in a sealed container, it will continue to produce heat and gas from the chemical reaction of dissolving the copper, possibly causing the container to burst forcefully."

I've heard all over the place of people saving the solution and reusing it, because supposedly over repeated uses the copper etched off the boards engages in a reaction with the muriatic/peroxide solution, leaving cupric chloride, which is said to be much faster and more powerful than just about anything else.  Then again, I'm not a chemist, so check it out for yourself and decide.  Search the forum or google for cupric chloride if you want.

Hey I have a bottle of hydrogen peroxide the kind ya get for cuts its 3% will that woork?

Paul already said to go with the 3%.

And also I have 30 ml of hydrocloric acid so my ratios would be 60 ml peroxide and 30 ml of acid. will that be enuph fow two board they are the ousb and the fuzz factory.

60 ml peroxide to 30 ml of acid is the same as 2 parts peroxide to 1 part acid, which Paul said to use.  As for there being enough etchant there, as long as the boards are submerged you have enough.

[Zedmin_fx]

Ok I just wanted to be sure it was not to weak. ok so then I wont make so much of it.

[Zedmin_fx]

Ok so late last night I etched the boards, it worked great! I found that since it got cold last night (buffalo ny) the etchant semed not to work as fast so I put a warm wash cloth under my etch pan, and it worked a lot faster. I just have one question. I put the layouts on my boards via iron transfer it worked but the ink wont come offf is that a problem or shall I try to get it off.

[morcey2]

Ok so late last night I etched the boards, it worked great! I found that since it got cold last night (buffalo ny) the etchant semed not to work as fast so I put a warm wash cloth under my etch pan, and it worked a lot faster. I just have one question. I put the layouts on my boards via iron transfer it worked but the ink wont come offf is that a problem or shall I try to get it off.

To get the ink off, use acetone.  It should be available wherever you got the muriatic acid.  You can use nail polish remover, which is mostly acetone, but I wouldn't recommend it.  sometimes it can leave a residue. 

Use the acetone outside and away from any source of ignition (cigarrettes, open flames, static-producing cats, children with flamethrowers).  The fumes are highly flammable and probably not to good when inhaled.  I usually put the acetone on a rag or paper towel, set it on the board for a couple of seconds, and wipe off the ink.  Usually gets everything the first time. 

Matt

[Zedmin_fx]

OK I will look around any store recommendations? I got the hydrochloric from a lab set in school ssh ssh ssh. would the film from nail polish remover be a bad thing? Just to say if I cannot find any acetone!

[Zedmin_fx]

Brake clean also works  just found that out.

[juse]

You can reuse the h202/Hcl solution.
Search for "reuseable etchant" here.
It's a bit slower the second time but worth the effort not to throw it into the water supply!

John

+1

After one or more uses, the etchant liquid should normally be a bright green color from the copper, and when it begins to turn brownish you can regenerate the solution by adding a tsp or two of peroxide. This adds oxygen & brings it back up strengthwise.  After awhile it gets harder to make the solution turn back to a green color by adding peroxide - that's when you add a tsp or two of the acid, usually every few batches of boards. As long as you balance it, the etchant can be used indefinitely.

I wear eye protection & a cheap respirator mask when I etch. Too easy to splash the stuff & I don't want to breathe it. I keep my etch in a big glass jar & I tie a couple of zip strips in series then loop one end around the board and just dip it into the jar, swishing it around here & there. Etches great in 5-10 minutes, then rinse off with a garden hose & clean with acetone. Pretty simple & cheap - just like me!

[Zedmin_fx]

yea all I did was put to pcb into into the etch bath and all of a suden it turned green. I didnt have gogles on or gloves o well I used an old fork and a hose to rinse it. but while they etched I palyed my guitar man was it cold. my parents wouldnt let me keep the etchant but I will just have to make more. O well.

[Chawk]

http://www.dickblick.com/zz452/03/