Resists for etching Aluminium with NaOH

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A user is seeking a cost-effective DIY method to etch holes in 0.3mm aluminum sheets using 5-10% sodium hydroxide (NaOH) and is exploring various resist materials. Suggested resists include enamel paint, acrylic paint, Sharpie ink, vinyl masks, and bitumen-based paint, with bitumen being the most effective so far. The user is considering 2-part epoxy paint and high pH surface paints as potential options, although they are difficult to source in small quantities. There is also a need for a solvent to remove the resist, with suggestions including acetone and IPA. The discussion raises questions about the necessity of chemical methods versus simpler mechanical approaches for such thin aluminum.
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I'm trying to find a cheap DIY method to etch holes of various shapes through 0.3mm Aluminium sheet using 5-10% Sodium Hydroxide. The idea is to apply a resist to the Aluminium then selectively ablate it off using a diode laser cutter and then dissolve away the Aluminium using Sodium Hydroxide. By cheap I mean resists costing say £20 in small quantities.

The Internet has suggested various resists to try including...

Enamel paint (only survived seconds in the NaOH!)
Acrylic paint (only survived a short time in the NaOH)
Sharpie ink (too hard to remove it all with the laser)
Vinyl masks (adhesive dissolved by the NaOH allowing mask to come off)
Bitumen based paint (Best yet but finally came off before all the Aluminium was dissolved)
Nail varnish (not tried yet)
2 part Epoxy Paint (not tried yet)
Kapton tape with Acrylic adhesive (not sourced yet)

I also need to remove the resist using a solvent of some sort (Acetone, IPA, gasoline etc) although I suppose I could also laser it off.

So can any chemists suggest other resists or which to try next?

The 2 part Epoxy Paint is probably my best bet but it's not very convenient and hard to find in small quantities. 1K Epoxy paint in a can apparently isn't good enough.

Any suggestions?
 
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I am not a chemist, but if it was my project I would try a paint intended for high pH surfaces (such as masonry).
Such a coating might be hard on the aluminum, but I would hope that it lasts long enough for the NaOH and wash. I would think it would survive the NaOH itself without a problem.

As an example: https://www.millerpaint.com/product/ph-surfacer-interior-exterior-primer-2/
 
Thanks Scott, great suggestion.
 
Why are you resorting to chemical means rather than simply poking holes? 0.3 mm is just aluminium foil?
 

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Thread 'Resists for etching Aluminium with NaOH'

I'm trying to find a cheap DIY method to etch holes of various shapes through 0.3mm Aluminium sheet using 5-10% Sodium Hydroxide. The idea is to apply a resist to the Aluminium then selectively ablate it off using a diode laser cutter and then dissolve away the Aluminium using Sodium Hydroxide. By cheap I mean resists costing say £20 in small quantities. The Internet has suggested various resists to try including... Enamel paint (only survived seconds in the NaOH!) Acrylic paint (only...
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