Author Topic: Acetic Acid (Vinegar) Smell from Lightweight Patch Compound  (Read 999 times)

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Acetic Acid (Vinegar) Smell from Lightweight Patch Compound
« on: December 14, 2020, 10:48:22 PM »
I've been smoothing a bit of unevenness in some pink foam scenery base the past couple of days with lightweight spackle and noticed an odd yet familiar odor from the patched areas - vinegar. Never noticed it before.

Anybody else experience this? It does not have the smell in the bucket, and it is dissipating to nearly unnoticeable this evening. So evidently it off-gasses acetic acid vapor during curing. At the moment I think it's a handy indicator for "not cured yet" when layering or using big globs of it for scenery. However, I do have to wonder if there are drawbacks and if the off-gassing doesn't completely abate over the long haul, with the acid vapor doing unfriendly things to track, for instance. Given that the instructions advise "do not use on plastic", I have to wonder if it's reacting with the XPS foam.

Anybody with more chemistry background than I want to hazard a guess?


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Re: Acetic Acid (Vinegar) Smell from Lightweight Patch Compound
« Reply #1 on: December 15, 2020, 04:59:03 PM »
Yes- It is obviously a chemical component, something to do with maintaining elasticity of the product.
I've been using these for years, and the odd container that hasn't been used in time eventually loses that moisture and viscosity content; material starts to harden, the smell is gone and the stuff has to be 'wetted down' again with water to make it pliable and usable. Last can was 15 yo!