Can't polish Humbrol Metal Cote

A big part of the battle with metallic paints is surface prep. Did you prep the basic surface at all?

Ahhhh see I only primed it (I had read many people suggest gloss black, truth be told it didn't look all that glossy when I sprayed it).  What did I miss?  Lots I'm sure!  I'm so glad I'm experimenting first.  Even unpolished this spray looks more metallic than the regular silver I used on my Original F-86 kit so I'm heading in the right direction.  So glad to be back into this hobby. 

You want the underlying surface to be as smooth and shiny as possible. I can't speak for the gloss black primer, but just polishing the basic plastic before the metalcote is applied will give you much better results.

I'm on it!  I've got a few spare kits around I'm testing on so I will definately do what you say.

I was thinking would using the spray in really cold weather cause that grainy surface?  I did the test outside on my deck in -8 degree celcius weather.  I will certainly try the next bit in my garage to see if there is a difference.

So I just did two pieces... one outside in the cold on my deck and one in my garage.  The Deck sprayed the same grainy texture...  the Garage was smooth and buffed up with 30 seconds of rubbing!  I'm just guessing, but I think the cold air may have been the culprit?  Plus I washed and buffed the pieces before spraying.

Who knows... but I think I'm ready to bring on that Mig!  Thanks again!