Natriumperoxidisulfate not working on alu?

[TELEFUNKON]

the masks used here probably won`t stand the mechanical strain.

[markm]

Why don't you do your etching mechanically with an air eraser?

the masks used here probably won`t stand the mechanical strain.

It wouldn't withstand something of that nature.
Isn't that like a sandblaster?

[Paul Perry (Frostwave)]

I saw some masking material the other day that is used to sandblast granite tombstones.
It is cut on one of those Roland vinyl sign cutters.. VERY expensive though.

[Paul Perry (Frostwave)]

The main thing if you are etching aluminum with sodium hydroxide, is that sodium hydroxide is corrosive to your skin. And clothes.
But, easy to dispose of, pour it down the sink... in fact, granular sink cleaner consists mainly of sodium hydroxide!! The white sludge is sodium aluminate. No problem.

***IF YOU SPLASH SODIUM HYDROXIDE IN YOUR EYES IMMEDIATELY WASH IT OUT WITH LOTS OF WATER***

[markm]

I saw some masking material the other day that is used to sandblast granite tombstones.
It is cut on one of those Roland vinyl sign cutters.. VERY expensive though.

Cool.
Actually, this is good to know if an etch project should go awry...........
...........sorry.

[RaceDriver205]

natriumperoxidisulfate

Eh? I thought the word 'natrium' had disappeared from our chemistry books.
Maybe the company who makes it sells chemicals with 'plumbum' in too.

[Paul Perry (Frostwave)]

It's only "sodium" in English & French (about the only thing they agree on!). http://www.vanderkrogt.net/elements/elem/na.html Note the symbol is Na, not Sd 

[JimRayden]

WATCH OUT - DO IT OUTSIDE - DON`T BREATHE !!!

TAKE PRECAUTIONS! WEAR A MASK !

IT`LL GET WARMER/HOTTER WHEN REACTING !

It`s aggressive to your lungs and hands. but it doesn`t make yellow stains.

Some white stuff (al-dioxide?) will fall out/dilute.

Hmm, I'm about to etch it. What about an open loggia? Will I have to deal with fumes like when soldering (only more harmful) or a huge white killer-cloud?

What if I make a weaker mix (like 5 grams per liter), will this tame the fumes a bit?

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

[TELEFUNKON]

TAKE CARE !
WATCH OUT!

It`ll just "steam" a little, like boiling water,
BUT it is AGGRESSIVE, CORRODING, CAUSTIC steam.

Don`t splash/sprinkle fluid!

Wear mask and gloves, and old clothing.

Have plenty of (running) water available for diluting!

[JimRayden]

TAKE CARE !
WATCH OUT!

It`ll just "steam" a little, like boiling water,
BUT it is AGGRESSIVE, CORRODING, CAUSTIC steam.

Don`t splash/sprinkle fluid!

Wear mask and gloves, and old clothing.

Have plenty of (running) water available for diluting!

I'll take extra care for the fumes and sprinkles.

Are there any certain materials or objects I would have to keep from the steam that it could harm too?

----------
Jimbo

[TELEFUNKON]

lungs and eyes

[markm]

I've never had an issue with steam coming from an enclosure while etching.
If it steams, it's WAY too hot and in the etchant WAY too long!
It really only takes a few minutes in the etchant to acheive results.
   MarkM

[TELEFUNKON]

markm: the above is NaOH-related, not ferric chloride.
While the NaOH looks/acts quite harmless when cold, similarly harmless to the yellow stuff
(it`s even used in some food),

it can get nasty, when heated and/or reacting.

[JimRayden]

lungs and eyes

Yes , this is the third post stating that. I have acknowledged it.

But are there any materials to react with the fumes. I don't want it eating away on the ceiling or any objects around.

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

[markm]

markm: the above is NaOH-related, not ferric chloride.
While the NaOH looks/acts quite harmless when cold, similarly harmless to the yellow stuff
(it`s even used in some food),

it can get nasty, when heated and/or reacting.

Apologies,
Didn't really realize.

[Paul Perry (Frostwave)]

While the NaOH looks/acts quite harmless when cold,it can get nasty, when heated and/or reacting.

WARNING! Sodium hydroxide is a poisonous corrosive solution that will dissolve your flesh, whether hot or cold. OK, it works faster when it is hot, as anyone who has prepared animal skeletons ((or made soap) can tell you... but it is VERY DANGEROUS, hot or cold.
As for fumes from sodium hydroxide.. I don't personally find them terribly bad, even when it gets so hot (eg when attacking small lumps of alumimnum) that it actually steams. Sodium hydroxide isn't volatile at all.

[JimRayden]

A live report from the scene: a whole bunch of fun bubbles are appearing from the bottom of the box (face down in NaOH), no sign of a killer cloud, though I avoid bowing myself over the etching pan. The reaction isn't too hasty, but it does seem to do someting. Perhaps you scared me off and I did a way weak solution.

I'll just wait and check the progress once in a while. I'm excited.

[Edit] Just added some hot water and NaOH powder. More bubbles, no "blackening" of the surface. Black flakes of transfer floating around. Still no killer cloud. Surface of the box is steaming when taken out of the etchant.

[Edit2] That makes me think... is the surface supposed to go black with NaOH at all?

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

[TELEFUNKON]

no: white
(where not covered with resistant stuff)
maybe your transfer can`t stand the "etchant"

[JimRayden]

In that case I'm on the right trail. There's definately some white stuff floating around when I stir it a bit. And bubbles. Lots of fun fun fun bubbles.

I'll keep it in there until I get the $uperpuma skull-effect.

----------
Jimbo

[Paul Perry (Frostwave)]

One problem with etching boxes..... is knowing exactly what the box is made of. Some are aluminium, some are a zinc alloy. Some aluminium is alloy as well. It isn't obvious exactly WHAT a box is made of, especially an unbranded one. A zinc box will be etched by hydrochloric acid, or ferric chloride. Aluminium will be etched by hydrochloric or by ferric chloride (violently) or by sodium hydroxide. I'm not sure whether persulphate will do much with aluminum or zinc.
All this means, is that probably some experimentation is needed. And various sludges of undissolved alloy components could turn up as well...
One for the experimenters: I used to get unusual colors by adding potassium permanganate to sodium hydroxide while attacking aluminium. Probably won't be attached firmly to the surface, though.
I guess the next thing will be electroplating boxes, using a resist mask!