Tetrosyl stone chip paint reaction

[michael1703]

This is an odd one, tetrosyl stone chip onto hammerite smooth on car chassis rails, its took on about 30% of the area but lifted and wrinkled up on the remaining 70%.

The underside of the car was thoroughly bare metalled and panel wiped, its not oil/grease/brake fluid, the hammerite took well and it was 2 weeks between hammerite hardening and covering with stone chip

Any ideas?

 

[Chickenjohn]

Hammerite is horrible paint. Just about everything except more hammerite will react to it.

Best thing is strip to bare metal, etch prime, then stone chip, prime and paint with chassis black paint.

 

[steveo3002]

yep hammerite reacts to nearly everything , its rubbish stuff

the stonechip is heavy with thinners and will react to alot of stuff though

 

[paintpot]

hammerite is enamel ,what you are putting on is solvent base .you have a reaction,its softened up the enamel,causing it to split or crack.

 

[Chickenjohn]

yep hammerite reacts to nearly everything , its rubbish stuff

the stonechip is heavy with thinners and will react to alot of stuff though

I've occasionally had stone chip react with zinc primer in a simmilar way. What I did to overcome this was get the workshop very warm and dust on the first few coats- this avoided the lifting of the primer layer, then some full wet coats of stonechip, when dry followed by chassis black paint.

 

[sprayerDrew]

Hammerrite has a very high content of silicone thats how it makes the hammered finish by silicone seperation. Plus tetrosyl stone chip is one of the worst to use it was covered here a few pages ago. Upol gravitex is the best and is ready to use no thinning required.
Drew