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General Discussions
A general discussion forum for the local chapter of IPMS Fresno.
What is causing bumps on my primer coat?
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North Carolina, United States
Joined: February 26, 2014
KitMaker: 13 posts
IPMS Fresno / Fresno Scale Modelers: 6 posts
Posted: Thursday, May 08, 2014 - 12:51 PM UTC
I recently painted a model with Vallejo white primer. Most of the coat went on very bumpy and not smooth. Part of the coat on the bottom was smooth. Is it air pressure that is causing this? Any help is appreciated!
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Alabama, United States
Joined: May 11, 2014
KitMaker: 2 posts
IPMS Fresno / Fresno Scale Modelers: 1 posts
Posted: Sunday, May 11, 2014 - 10:33 AM UTC
It can be the air pressure. If you are shooting with much more than 20 psi the primer may dry in the air before it gets on the model. Also, I have found it helps to use a bit of Vallejo airbrush thinner to get a more smooth finish. Also light coats slowly built up to full coverage will help to not get the rough surface. The Vallejo white primer seems to need a bit more thinner than the other two colors, or at least in my use of it.

Good luck! I hope that this information will be of some help for you!