What can I use to color clear acrylic

[evansd2]

@Xabbess

on the surface of acrylic

In my case it was through the entire piece. Far more than surface.

Acrylic crazing fail

I’ve known for a while that acrylic plus alcohol is supposed to lead to cracks/hazing, commonly referred to as “crazing”. I’d never actually seen it until now. Here’s a cut piece of extruded acrylic. [image] Now I placed alcohol ink on it, thinking I might be able to get a stained glass effect. Like I said I had never seen crazing before, so I wondered if it were a myth. After about 20 seconds I noticed the cracks starting in from the edges. [image] The cracks were growing, slowly enou…

@jamely

mirror acrylic, then cut and engraved with no crazing. But used on a fresh engrave, instant crazing.

This makes sense, as the alcohol propagates existing cracks, much like water and tempered glass (e.g. windshield cracks that grow over time)

Also this makes sense because mirrored acrylic is extruded. Extruded has far worse alcohol-induced crazing than cast.

@wesleyjames

heat treatment

@jamesdhatch

let it cool

AKA annealing. This also makes sense because you’re relieving the internal stresses that causes the cracks to propagate. This is essentially how cast is made, so this all tracks.

If you do this, especially with mirror, you better have a very flat surface to cool it on. If you heat it enough that it slumps and cool it on an uneven surface, you will immediately notice it in the mirror; the piece will be potentially ruined depending on your needs.

More on acrylic annealing:

https://community.glowforge.com/search?q=Anneal%20acrylic

And of possible interest, a few YouTube videos about how acrylic is made:

How It's Made, Acrylic.

Acrylic sheet process

A short introduction on Cast vs. Extruded acrylic sheets.

How ACRYLITE® extruded acrylic sheet is made