Just a simple why...

Sounds like maybe a little heavy and the surface dried way before the underneath of it.  If only in places it might be some contamination of some sort that the primer pulled away from.

Hi Luis,

 Have you thought about just soaking it in some isopropyl alcohol to celan it? It is fast and will save details from the sand paper.

Just a thougt,

Kevin

I've been tinkering with Moebius' Grandpa and Hermann Munster kits and had similar issues, Luis. I used both Tamiya primers (gray and white), as well as a Krylon black primer. 

Even though I had washed the parts in soapy water, I don't think that I manages to get all of the oil and mold release off the surfaces. I'm fairly certain that is what caused my problems. 

I wet sanded out the problem areas and gave the parts a good cleaning, then wiped them down with Plastic Prep before recoating. The primers all dried perfectly.

Some figures in hobby kits are cast in vinyl.  Vinyl is notoriously hard to paint- I have not found a good solution yet.  Someone needs to develop a good primer for vinyl.  I have friends who tout various primers, but I have never got any of those to work well.

Don Stauffer

Some figures in hobby kits are cast in vinyl.  Vinyl is notoriously hard to paint- I have not found a good solution yet.  Someone needs to develop a good primer for vinyl.  I have friends who tout various primers, but I have never got any of those to work well.

 

 

From what I have read, you need an acrylic primer for vinyl. I am attempting to finish a vinyl dinosaur model, and I use Vallejo primer. Then used MM enamel over the acrylic primer with no issues.

Edit: But, in pianodog's case, his model is plastic, not vinyl.

I can tell you exactly what the cause is. You used Krylon paint. Don't use it! They're garbage. I've had a couple kits ruined because of that garbage paint. Use Rustoleum Primer. I've used it with zero issues. Goes on nice and smooth. What's even better - they're wet/dry sandable.

Krylon paint have been banished from my hobby forever. GARBAGE! GARBAGE! GARBAGE!!!

BlackSheepTwoOneFour

I can tell you exactly what the cause is. You used Krylon paint. Don't use it! They're garbage. I've had a couple kits ruined because of that garbage paint. Use Rustoleum Primer. I've used it with zero issues. Goes on nice and smooth. What's even better - they're wet/dry sandable.

Krylon paint have been banished from my hobby forever. GARBAGE! GARBAGE! GARBAGE!!!

 

It seems you feel strongly about those paints Blacksheep.

I will heed that warning.

Gary

THank you all for your answers they mean alot for me, now how can I fix the issue... wet sand, clean with alcohol... suggestions?

Don Stauffer

Some figures in hobby kits are cast in vinyl.  Vinyl is notoriously hard to paint- I have not found a good solution yet.  Someone needs to develop a good primer for vinyl.  I have friends who tout various primers, but I have never got any of those to work well.

Apparently, that's where Badger's Stynylrez comes in - hence the name: styrene, vinyl, resin. Haven't tried it but heard good things.

And yes, chuck the Krylon.

I just want to write a little note of thank you to each and everyone that took the time to write something regarding my issue, I ended up using Stynylrez Back and wow, what a difference, absolutely marvelous, unfortunately the damage was already done to the peace but I will finish it anyway, lesson learn. Once again thank you.