primer drying

   / primer drying #1  

ugabulldog

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GA
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'04 MF 451 diesel shuttle shift w/ MF 1040 loader
A friend sandblasted then primed my wheels with a spray gun, he went back over them with primer not long after, it was barely dry to touch. The next day I put out in sun to help dry, and when I went put back under shed (24 hrs after painting) I rolled across ground (heavy rear wheels) and the primer came off. Did he do not wait long enough between applying or do they need to just dry more? thanks
 
   / primer drying #2  
He may not have wiped the dust off, or cleaned with a tack rag.One more he may not have stirred the paint, theirs drying agents in primer. imo
Army Grunt
 
   / primer drying
  • Thread Starter
#3  
He may not have wiped the dust off, or cleaned with a tack rag.One more he may not have stirred the paint, theirs drying agents in primer. imo
Army Grunt

he blew off with air compressor, pretty sure he stirred enough but could be wrong... thanks

should it be ok if I just let it dry longer before handling or spraying with paint? (I will put it out in sun again today, wednesday, to help dry, was painted moday afternoon,... boy those 28" are heavy without rolling!!!)
 
   / primer drying #4  
might not have cleaned the rim with a dewaxing solvent. when i see primer sheet off, it's usually a bonding problem, or the solvent in the primer made something else lift.

soundguy
 
   / primer drying #5  
All primer that I've used or seen used,dries very quickly. Make sure he wiped the wheels down with a dewax solvent . ...and used the right solvent for the primer. Sounds like a compatability issue somewhere along the line. I wouldnt spray paint until you have it figured out
 
   / primer drying #6  
rim may be impregnated with a contaminant too.

soundguy
 
   / primer drying #7  
If the rims were blasted to bare metal. Like said before, there maybe something in the metal. That primer may have to come off. If there is any possible doubts about primer adhesion. Remove the new primer. Wipe down the rims with a good Wax / grease remover. Then use a metal etching primer. You should not have any problems after that. Metal etching primer is a little high, but I have never had a failure when using it. Epoxy Primer is also a great base, to start off a new paint job.
 
   / primer drying #8  
Anytime I've done metal spray priming the primer has dried in minutes. That was with "thinners" based primer. Epoxy base could take longer to cure, but it would be a matter of an hour, not days.
If he used epoxy primer then he may have a problem with his catalyst....in which case it will never dry properly
 
   / primer drying #9  
Since he sandblasted the metal, blowing the dust off with a blow gun is not good enough. There is still a dusty residue embedded in the metal. Use a cleaner and wipe the bare metal down. (And be sure the primer is applied properly.)
 
   / primer drying #10  
Too many unknown variables to say for sure.

A properly sand blasted surface should be clean enough that you only need to blow it off, and prime it. That is assuming the air supply used to sand blast it was clean enough. If your air supply is not properly filtered to remove oil and other contaminates, then you would need to wash it with a solvent.

Yes, you should etch it before you prime it, unless the primer you use says it is unnecessary, most primers will need the etch for best adhesion.

If it is an air dry primer it should have dried by now, unless he really put it on way too thick. Which would be tough to do, but I have seen it done.

If it is a 2 part primer, it should have hardened after a number of hours at 70 degrees F or greater, regardless of the thickness.

It is possible the product is defective. Or, the wrong type or amount of hardener or solvent was used. Using either too much, or not enough hardener can easily result in improper drying.

If it is not dry soon, I would get a couple spray cans of paint stripper, that should easily remove it. Then, start over.
 
 
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