Etchants: How many are there?

[JimRayden]

Dispose all of your acids, for electrolysis is in town!

->it's safer
->it's cheaper
-> it requires water, salt and electricity
But what's most important
-> IT'S FUN TO WATCH!

Oh yes, the bubbling of the anode is a remarkable sight, as is the green planktonic-looking residue from the copper board. It works like a charm. The demands for a well-ventilated workplace still apply though.

From now on - only photopaper and elecrolysis for me. I'm gonna build me an electronic etchin' machine.

Next up: let's see how Al boxes act with this method.

-----------
Jimbo

PS: -> You can collect the rising Hydrogen to make Big Boom.

[JimRayden]

Got carried away and blew my 24V wall wart. Do not let the anode and the cathoode touch for too long.

---------
Jimbo

[coxter]

A million thankses! Enough with acids and alkali for me, Jim goes electro!

If it does work, I don't understand why it isn't the preferred method for everyone (especially newbs) in electronics, as it seems way safer than the usual "evil liquid" we use.

---------
Jimbo

R.G already explained why in the earlier post. I've got no access to any etchant alternatives, but luckily i found some hydrochloric acid in some hardware store.

Tested one drop on my alluminium enclosure, and it EATS like a feasting maggot. Looks like a very dangerous potion, it was fuming like mad when i just opened it.

Will update you guys again when I do more further testing.

[zjokka]

I am about to etch my third or fourth aluminum box, and I really want to make some progress now. There are many ways to etch and I'm really interested in electrolysis, but have been using HCL + H2O2 up till now for pcbs.

Seems to be a bit too violent for aluminum. It starts eating through the transfer, and Paul Perry I think it was suggested that HCL would do, but then it would have to be diluted if I read

i found some hydrochloric acid in some hardware store.
Tested one drop on my alluminium enclosure, and it EATS like a feasting maggot. Looks like a very dangerous potion, it was fuming like mad when i just opened it.
Will update you guys again when I do more further testing.

Any news Coxter?

Furthermore and important: you cannot store and reuse HCL+H2O2 for long. You can always get the reaction going by adding some fresh H2O2. Maybe that why I had to etch for such a long time last time.

If it does work, I don't understand why it isn't the preferred method for everyone (especially newbs) in electronics, as it seems way safer than the usual "evil liquid" we use.
---------
Jimbo

Really curious! But could you give some description of your setup?

thanks
zj

[JimRayden]

If it does work, I don't understand why it isn't the preferred method for everyone (especially newbs) in electronics, as it seems way safer than the usual "evil liquid" we use.
---------
Jimbo

Really curious! But could you give some description of your setup?

thanks
zj

Naah, blew my wall wart and haven't found the initiative to buy another one. I guess I'll start trying the electrolyses again when I run out of acids. I had a short e-mail conversation with Seljer and he had some pretty good results, perhaps he wants to chime in here.

----------
Jimbo

[JimRayden]

This thread makes me wonder... how'd Coke work?

--------
Jimbo

[Seljer]

It does work at dissolving aluminium foil

I was using a laptop power supply capable of 2A at 15V, I had a small lightbulb wired in series with the the actual electrolytic cell to limit the current (though I still blew my multimeter, not seeing that the fused amperemeter input was limited to 300mA)

Naah, blew my wall wart and haven't found the initiative to buy another one. I guess I'll start trying the electrolyses again when I run out of acids. I had a short e-mail conversation with Seljer and he had some pretty good results, perhaps he wants to chime in here.

----------
Jimbo

I'll try to seriously try it out on some enclosures this week. I allready attempted once but the acrylic paint I used to mask off the larger areas on the box didn't seem to really hold so I had to stop.
This weekend I painted the sides of 2 enclosures with spray paint as in markms excellent tutorial, going to transfer the artwork when I get the chance, as well as use some enamel paint I bought which will hopefully hold up this time.

[coxter]

I didn't use any H2O2, its just plain HCL acid.

I'm not sure about the concentration, but it eats into the alluminium very very well... Maybe cos I didnt dilute it.

Its not exactly violent, it just bubbles alot... And if my chemistry doesnt fail me I think its Chlorine gas thats gushing out.
Thats my biggest problem yet... I live in an apartment, and dont have any garage or backyard. So I tried it in my toilet
thinking that it'll be safe since i have a clean water supply in case of any spillage.

But man was I wrong... I almost choked and puked blood in there!

I dont have any access to PNP, so basically on the test run, I just spraypainted the backplate of my enclosure and use a pin to scratch out a design to etch
It turn out pretty alright. But for PNP, I really dont know, I'll buy some next week or something.

Or can anyone post me ONE piece of PNP blue? I'll pay for it + shipping

Used a ruler on the painted enclosure to scratch a straight line to check how clean the line would turn out.
I would say its pretty straight and clean. HCL is a good and cheap and easily available etchant.

Cons: VERY DANGEROUS, DEADLY FUMES.

But its just the only thing available to me. So I can't complain.

[zjokka]

I didn't use any H2O2, its just plain HCL acid.
I'm not sure about the concentration, but it eats into the alluminium very very well... Maybe cos I didnt dilute it.

My bottle of HCL, I believe only says concentration of 27% or so (have to check) certainly not pure HCL (maybe not impossible)
Will try and dilute it like before 75% water and 25% HCL or so. For pcbs I use 75% water, 20% HCL and 5% H2O2.

Will test on some scrap metal first probably. 

Or can anyone post me ONE piece of PNP blue? I'll pay for it + shipping

Just laser copy you design on INKTJET picture paper instead. This is how I do it -- I even got some pnp but don't use it.

Works great

[coxter]

I need to clarify what you mean by picture paper. Is it normal printing paper for general usage or is it paper used for printing photos (or any equivalent)?

[zjokka]

It's just what they sell to put in picture pictures, glossy on one side, dull on the other.
They are so many brands and qualities, but that's not really important.
I found that using INKTJET paper and LASER copying the layout on this works best, it peels off better than laser picture paper.

You could you transparent sheets, but they are not so heat resistant as the paper, off course.
That's is why PNP is so heat sensitive, I believe.

zj

[Minion]

Hi, yes I use the Normal Picture photo paper that you use to Print out Pictures on, It seems very heat resistant ,actually the more heat you use the better the Toner transfer, at least for me it is....

So you say that PNP is very heat sencitive?? How much heat is To much?? Or not enough?? I don"t want to ruin the only 2 sheets of PNP I have because My Iron is too hot......


Thanx

[zjokka]

Hi, yes I use the Normal Picture photo paper that you use to Print out Pictures on, It seems very heat resistant ,actually the more heat you use the better the Toner transfer, at least for me it is....

I couldn't agree more.

So you say that PNP is very heat sencitive?? How much heat is To much?? Or not enough?? I don"t want to ruin the only 2 sheets of PNP I have because My Iron is too hot......

I'm just remembering people putting their iron normal temperature, but I only use picture paper, so no expert. With picture paper, I always use hottest, 'linen'.


Now last night, I tried to etch a box using plain HCL out of the bottle. Tested on aluminum sheet, and in some minutes it was gone indeed. Working outside in the dark wasn't a good idea at all, again I overetched.

Pure HCL is very potent, and it problably needs some dilution. After a minute of 7 (too long I know) part of the toner started coming off and the overal problem was again that the etchant ate through the toner.

Minimal etching time is important, especially with very strong solutions, it seems. I'm always scared that my sanding wasn't up to scratch so I always want a very deep etch, but that is no alternative to proper sanding.

Now let me get a picture (one minute).
zj

(edit: add pic)

[coxter]

One question, how long is too long, say with pure HCL

[John Lyons]

Why don't you just dilute the HCL same as you do for etching boards? 3 parts Hydrogen peroxide H202, 1 part HCL.
HCL is way too strong to etch with toner transfer by itself.

John

[zjokka]

The HCL certainly needs dilution, but not with H2O2. The mixture I use for boards is 75% water, 20%HCL and 5% H202 only.
I don't think getting a good etch is a criteria, anyone of the mentioned solution works.

The art is in etching a very short time. I think, 3min or something is more than enough.
All depends on the surface to be etched, of course.

The problem with pure HCL is that the fumes are so heavy, it's very hard to check your box for progress.

Why don't you just dilute the HCL same as you do for etching boards? 3 parts Hydrogen peroxide H202, 1 part HCL.
HCL is way too strong to etch with toner transfer by itself.

John

One question, how long is too long, say with pure HCL

[coxter]

I JUST tried etching with Hcl on a copper board! IT DOES NOT WORK !!! ARGH!! What awaste of effort

Is that why i need Peroxide?

[John Lyons]

H202 as sold as hydrogen peroxide for medical use is a 3% solution. So it's 97% water. Close enough to what you use zjokka.
You could use 15% HCL and 85% H2o2 (3% solution with water) and get aproximately the same ratio.
What form do you buy the h202 in, is it a solution of water and H202?

John

[David]

OK, dudes.  Chemistry and safety lesson.

For you hydrochloric acid fans, if you're in the US (possibly elsewhere, I'm not enough of a world traveler to say), go get yourself a bottle of muriatic acid.  This is available at pool supply stores, big box stores, possibly some department stores... you get the drift.  OK, this might be enough to etch on its own, but it works a lot better and FASTER if you put a catalyst in.  If you've been using drugstore 3% peroxide, you're waiting too long.  Swallow your pride and go to (with your significant other or a female family member if you have to) a beauty supply store and get yourself a bottle of 40% peroxide.  You want the clear stuff.  Note:  40% versus 3%.  Put your board in a plastic container that's not a whole lot bigger than it is.  Pour only enough muriatic acid in to BARELY cover the board.  Pour some peroxide into the dish.  When you see bright green threads sloughing off the board, your solution is strong enough.  Move the board around constantly and watch it like a hawk!  Take it out frequently, dip it in a handy bowl of water to stop the reaction, and check its progress.  Repeat.  When you don't see copper between your innermost traces, remove the board and rinse it.  Now.  If you have a little copper remaining between your traces, you can gently cut it with a knife and break the connectivity.

OK, the safety.  The nearby water bowl is a must and should be big.  It should only be 1/3 to 1/2 full.  Use a nonmetallic object to move your board around and to pull it out.  Don't touch the board with your fingers.  The acid solution will cause burns.  It probably isn't too kind to your lungs if you breathe it, so don't.  After etching, remove your board and put it aside to dry.  Dump your acid solution into the water bowl.  Dump the water bowl down the drain only if you know for sure the plumbing isn't metal.  If there's a chance it's metal, dilute the acid solution further with several gallons of water, then dispose of down that drain.

[Seljer]

^^or neutralize it with baking soda?