Jump to content
Model Cars Magazine Forum

Recommended Posts

Posted

I had to do a small repair on a 73 GTO resin car I built awhile back.  The body was painted with Tamiya fine primer and Testor's lacquer followed by a lacquer clear coat (maybe Testor's, maybe Krylon). I never had any issues with the paint. It's been on there probably over a year, maybe longer. I picked it up without gloves on and it left fingerprints in the paint. The paint was lacquer, which dries really fast by evaporation of the solvents and it has certainly been on there long enough to cure. Anybody else ever had this happen? The paint felt soft as soon as I picked it up.

Posted

My first thought is that since it is your own casting, do you have other models you cast using that same exact resin and painted with the same paint combo?  Are those sticky too?

Your post also implies that the paint was not sticky shortly after the model was painted, correct?  The stickiness developed after a relatively long time?

Posted

Other cars were painted in a similar fashion and the paint cured fine. The paint o this one was not soft before. I took the cars to a show and handled them with no issues. It seems to have taken place over time, which to me is exactly the opposite of what should take place, especially with an evaporative paint like lacquer which tends to get more brittle over time.

Posted

Strange or unexpected chemical reactions between polymers can develop over time.

Nobody expected the dreaded "tire melt" phenomenon that occurred between some vinyl kit tire compounds and some styrene kit compounds.

Sorry, but that's all I've got on this one.

Posted

If the paint dried at one time it would not be a paint issue. I believe the resin had a short shelf life and is breaking down beneath the paint.

  • Like 1
Posted
1 hour ago, DoctorLarry said:

Other cars were painted in a similar fashion and the paint cured fine. The paint o this one was not soft before. I took the cars to a show and handled them with no issues. It seems to have taken place over time, which to me is exactly the opposite of what should take place, especially with an evaporative paint like lacquer which tends to get more brittle over time.

It is possible that it is the resin that is leaching some chemical out and affecting (softening) the cured paint.  Just like the "tire melt" with vinyl leaching plasticizer (thick fluid) which then softens the plastic in contact with it.  That also takes months or years to happen.

That's why I asked you if you had other models made with the same resin and painted using the same paint to see if they were also affected the same way.  Your original post seems to indicate only a single model having the problem, but the post I quoted now seems to indicate "cars" or multiple  models, but still no answer as to whether a single or multiple models were affected.

Posted

Single model. I checked three others and the paint was fine. Maybe it was the Testor's formula?  Two others were painted with Dupli Color auto touch up and the third was Krylon white lacquer.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...