Airbrushing problem

I bought some automotive grey primer and mixed it about 50% with lacquer thinner. Started spraying perfectly but soon it looked like I was spraying cotton candy on all the edges. What caused this???????

It's a thinner issue. It happens when you are not using enough thinner, but it could in part be because the thinner you're using is not entirely compatible with the primer you're spraying. Try adding more thinner (the automotive primer I airbrush needs 4/1 thinner/primer), and switch to the manufacturer's recommended thinner if you're not already using it.

Welcome to AF!

... or, try to lower the psi on your air regulator, sounds the primer is drying soon before reach the model. good luck.

Those are both sound reasons for this issue. I ran into the same problem while spraying my brother's 1:1 motor cycle. I thinned it out a bit more (about 2:1 thinner to paint) and lowered the pressure. It came out nice and smooth, no cob webbing, flowed out nicely, no runs or drips. I love the stuff now, I hated it at first. that stuff was THICK!!!