Sanding your primer?

Try a little dry sanding of any imperfections.
The smoother the surface the more glossy the final coat will be. The drill is usually prime then sand then prime then sand...until you have a surface you are happy with.
Wet sanding can be problematic as you do not want any moisture in the primer when you spray the top coat. You could wet sand but then be sure to let the model dry thoroughly.
Also, try not to touch the finished primed surface with you fingers once it is ready, the oil form your hands can cause blemishing. Medical exam gloves are useful to handle prepped models and in general to keep your hands clean.

Oh, and a tack cloth at the end to catch dust and such. A nice clean rag can do a similar job.

I don't "sand" mine in similar situations.  I go over it, lightly, with a non-metallic scouring pad - not sure of the brand , but its sort of greenish gray and about 1/4 inch thick, quite flexible, like thick cloth, and looks a bit like filter material for an AC unit. I buy it at the grocery store.  I rub lightlyjust  to take off anything like dust or whatever that might have clung to it, etc.  then I just blow it with air from a compressor to get all the dust off it and go.  So far that has worked well

The primer can serve three purposes.

 

1.   Allows the bond between the final coat and the Base material.

 

2.    Serves as a filler.

 

3.    Seals the base and keeps the topcoat from attacking it.

 

 

#3 sounds like it might have been your culprit, the final coat is attacking the filler.

 

Also make sure you allow time for the filler solvents to completely evaporated or you can trap them in when you primer and they will eventually bubble the finish.

 

Quite common in antique auto restoration and sometimes does not show up till much later.

You can actually paint right over the Tamiya primer without sanding. But you can get one of those scotch brite pads and lightly go over it before painting if you wish. The bad thing about trying to sand thin primer like the Tamiya is you will sand right through it. In some cases, I just wash the model well and let it dry a day, then paint.

Rob

Thank you Gentlemen, for the useful information we can all use.

Ralph-RJL

There are sanding primers and those that don't require sanding and are used to bond to particular surfaces. The latter are harder and easily scratched when you try and sand it. You should use a sanding primer if you want to smooth out imperfections. I haven't looked for sanding primers in a hobby shop but they can be found at home stores and automotive paint stores.

 

Pete

I appreciate this thought and the others.  Maybe sanding primer isn't in hobby stores because it would tend to be heavier and take out the fine details.  This is why I'm using lacquer  products instead of enamel.

Keep the thoughts coming.

Alan