etching aluminium

[redcollective]

Hello all,

I'm trying my hand at the mini photon stove (http://www.britishblades.com/home/articles.php?action=show&showarticle=33) as descibed on british blades. I've got an idea to try and etch a bushcraftUK 'leaf' symbol on the side of it.

Couple of thoughts/questions

This doesn't appear to be a high pressure device but could etching significantly weaken the alu can?

Is there an environmentally friendly way of etching aluminium without resorting to anything exotic?

red

[arctic hobo]

Are you experienced in etching alu? Because I wouldn't have said it would be easy - I'm thinking of that oxide coat. And if the etch will be deep, then yes it will weaken it as alu isn't awfully strong. Simple solution - make it thicker.

[Great Pebble]

You can use a dilute copper sulphate solution to "paint" it.

How dilute and how well it takes is.....variable.

Adds:- you could also have a go with Aluminium Etching Primer which will be familiar to anyone who's ever repainted a Landy from bare metal.

[redcollective]

Hmmmm, well my first effort is not worth doing anything fancy on - there are some dints and tiny folds in the alu where I had to shim the bits together. Looks decidedly utilitarian to say the least - will let everything cure overnight before looking at it again.

I've got some hammerite heat resistant paint somewhere - perhaps I'll paint the whole thing in that before drilling the jets - anyone got any idea how hot a stove like this might get? the hammerite paint will take 600 dec celcius if I remember correctly. images/smilie/dunno.gif

red

[arctic hobo]

Don't know what you're using it for, but if it's metalwork, to anneal or quench steel you must heat it to 800 C. The point at which it glows a dullish red.

[george]

what about caustic soda? I read somewhere that that can be used to etch aluminium.
Anyone know?

George

[KIMBOKO]

Any alkali will dissolve aluminium to a greater or lesser extent but caustic soda is the easiest to obtain. Be carefull with the caustic soda.
Put a resist over the bits you dont want to "etch" and place in a caustic solution. The alkali dissolves the alumiun oxide surface allowing a reaction with the aluminium. The bubbles given off are hydrogen so be careful.

[stevec]

why etch it? why not go down the anodise route? then there is no problem with thinning of the material. i seem to recal its quite simple to achieve, and is should be possible to add colour as well. try a internet search on anodising alu.
sc

[KIMBOKO]

Try this
anodised aluminium (http://easyweb.easynet.co.uk/~chrish/t-anodis.htm)

[redcollective]

Interesting idea - but perhaps overkill for a stove which cost almost nothing to make in the first place - those instructions are detailed however (I wish I understood half of it!!) and probably a good resource for anyone making something they really want to finish professionally - thanks for that link Kikimbo.

I think I'll see if some hammerite heat resistant paint will stick to the stove and survive a proper burn.

Cheers