Yepper, Shaggy's right. The solutions soften the decals so that they conform to the surface detail. This helps avoid "silvering", which you may or may not have heard of.
Silvering is visible in the areas where there's clear carrier film on the decal. (usually around the edges and in the center of some markings) It occurs when parts of a decal are not adhereing well to a model. Air is trapped underneath, between the decal and the surface of the model, taking on a "silver" look.
Setting solution alone can help to avoid this, but often times you have to prick a tiny hole in the decal or make a small slice with a sharp knife. This will allow some of the solution to flow into the void and soften the decal so it snuggles down. This is why many companies have two part solution systems, one to put down underneath the decal and the other to put on top. Personally, I've turned to Solvaset at times and just used it in the same manner.
Hey Shaggy! I'm gonna do a model of the Mystery Machine and I was wonderin' if you could give me some reference details for the interior? Is it, like, really groovy in there, or what? Like, wow!
Sorry, couldn't resist!
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