I keep having problems with my automotive acrylic primer. One of the problems is that becomes very rough and uneven when i spray it on my AFVs. Is it due to spraying too much of it at a time? The other problem is that when i cover my vinyl tank tracks with it, and it just cracks up and flakes off when i bent the track. Should I be using different primer? Give me some advice on this guys.

i have never used auto primer, but by the sound of it , you may well be putting it on to heavy..do you do a few fine coats and end up with this problem? With a can you just dont have the same control over the amount you spray or how much you thin the paint . Also..do you wash the model down with soap and water before you spray it?

I've had the same problem in the past Arminas, one thing that seemed to help was submerging the primer can in warm water for several minutes before spraying the model. It's a tip I found here that says it helps the paint flow better and it did seem to help, that and do as John pointed out and keep it to several thin coats rather than one coat. Hope that works for you!

I think ur right : i did put primer on quite heavily. No I didnt wash the model with soap and water but i dont think that it would make that much difference. Do u guys think that i should use the same auto primer on vinyl tank tracks or do i need 2 use different one?

For treads, I would use a paint called Accugrip or Flexigrip. It is an acrylic and is used mainly by railroad hobbiest. It is flexible after it dries and can be applied with a brush leaving no marks. Also can be used to weather. It can be found through Walthers and some hobby suppliers. Comes in a wide range of colors.

Arimas, You will be amazed at how much washing off the oil and dust ( or anything else that clings to the model) will help in the overall painting.

I will try to get hold of that flexigrip stuff and thanks 4 your advice.

I agree with Moezilla in regards to warming the primer first in a tub of warm water. It helps the primer atomize better and provides a more even flow from your air brush. (ditto if you're using primer and or paint from a aerosol can) In regards to it being rough, I was thinking perhaps that you've might of set your pressure too high and it's drying as it hits the surface of the model. Sometimes this will give primer..and paint a rough texture.

Just my two bits worth.
Good luck

I use ModelMaster metalizer direcly on vinyl tracks. This typically sticks very well and won't crack in normal assembly.