BF109 E4/7 Trop Tamiya build clear gloss coat leaves residue

[MattH912]

I am applying a Mr Color GX 100 Super Clear III Gloss to my model to prep for the decals but when the clear coat begins to dry it leaves a sand like residue, which when it fully dries it can be wiped off with a fine micro fibre cloth. Im just curious what could cause this as I shake the bottle heavily and all mix this with Mr Color SLT at a ratio of 50/50, I have used other clear gloss coats such as the Tamiya offerings and this doesn't occur so much. Any help would be much appreciated as to what could cause this odd occurrence. 

 

 

 

 

 

 

[Dogtail2]

Looks as if it may have reacted with the paint underneath.  Seems mainly in the area where you have applied exhaust staining.

[Whistlekiller]

I had this happen with Vallejo gloss varnish. I now use Pledge with no problems. I’d add that I find the Vallejo Matt varnish absolutely fine.

 

[CharlieNZ]

I notice it is worse at the wing root, this looks like it's caused by turbulence in the atomized paint in the corner, where instead of lying down nice and smooth, the paint mixes with partly dried over spray as it all swirls around at the intersection of the horizontal and vertical planes.