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?