Acrylic and isopropyl alcohol chemical reaction

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John Mac
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Joined: Sat Jan 12, 2019
Location: Glasgow
Country: Scotland
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Laser Machine Make or Type: Chinese laser 500*300
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Ruida Controller: RDC6442
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Recently done a bit of engraving and cutting, and I cleaned the work with isopropyl alcohol, cracks started to appear on the piece that I cut out and cleaned. Was wondering if this is common, and if there is a chemical reaction, when I checked the piece that I cut from there was no cracks appearing. Just on the pieces that I cleaned
Doug Fisher
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Yes, this is a known issue when alcohol is applied to the cut edge of extruded acrylic.
John Mac
Posts: 6
Joined: Sat Jan 12, 2019
Location: Glasgow
Country: Scotland
Nickname: Weeman
Laser Machine Make or Type: Chinese laser 500*300
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Ruida Controller: RDC6442
Windows Version: 10

Thanks Doug it took me 6 cuts, before i looked at the waste and saw it was a perfect cut, wont be using it again in future
Jeanfrancois Durette
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Laser is at my shop, I will check for the missing info. My staff know Windows. I am a Mac literate at this time.

It breaks the chemical chain of the acrylic molecules. I shows as cracks. Acetone and MMA can do the same cracking. It can happen with many acrylic parts, not just extruded. Injection moulded, cast moulded (like dentures), embedding grade PMMA, cast sheets as well, although some are more reacting than others. I try keeping the film while cutting with my laser. no need to clean the cut parts, except remove bits of film in texts. best
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