Resists for etching Aluminium with NaOH

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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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