Help with painting

[simmy]

i have resprayed some alloy wheels, however the paint has started to flake off after a few days.

What do you think has caused this?

I have a feeling that i may have heated the primer can too much(I did leave it in a bucket of hot water for quite a while), and when i primered the wheels although it covered the whole surface, maybe the primer coating was too thin. i only used 1 can to primer all 4 wheels, and it covered the whole surface.

Also if i was to use too much thinner, what would happen?

Your input will be much appreciated.

Thanks

Simmy

 

[brightspark]

what primer paint did u use . was the surface smooth. aluminium is best etch primed preferably 2k on a roughed up surface. what paint did u coat over the primer with

 

[steveo3002]

give us a run down of how you prepped them and exactly what materials

first thoughts are ...not rubbed down enough , or the primer was so hot it went on almost as dust and didnt stick

 

[simmy]

what primer paint did u use . was the surface smooth. aluminium is best etch primed preferably 2k on a roughed up surface. what paint did u coat over the primer with

Thanks for the reply.

I used the 2k upol high build primer, and then i used 2k paint. after using the primer the surface was smooth.

I refurbish wheels regularly, but never have the problem of paint flaking off. However in the past i used much more primer, but then it occured to me that i can use less primer when heated up and still cover the whole surface.

Im thinking if its not the primer, can it be due to the cold weather? I have been prepping the wheels in the cold, but after using primer i have put the wheels under very strong infrafed heaters and then when completely dry straigh after i paint them.

 

[simmy]

give us a run down of how you prepped them and exactly what materials

first thoughts are ...not rubbed down enough , or the primer was so hot it went on almost as dust and didnt stick

All the prepping was right, i refurb wheels now and again. The last 2 sets i have done the paint has come off quite easily, im thinking its either the primer or due to the cold weather. The finish on the wheels is excellent, its just the paint has started to come off lightly.

What is essential for the paint to stick properly, especially in the cold?

 

[steveo3002]

you need the wheel at decent room temps ( note the wheel will take forever to warm up even in a hot room) and have the cans at a decent temp , a bucket of warm water should be fine

any bare metal you need etch primer

 

[MG David]

Unless you have surface issues that need highbuild to smooth out I would not use it on wheels. Having prepared the wheel I would use U-Pol Acid 8 etch primer and then your 2k paint on top. If you do need highbuild I would still put the etch primer on first.

Epoxy primer would no doubt work in place of etch primer but I have not yet used it myself.

 

[langy]

As has been said temp is the key but don't use 2k hi build on ally, it won't adhere properly, Epoxy is your answer and by far the best or acid etch if your old fashioned.

 

[simmy]

Unless you have surface issues that need highbuild to smooth out I would not use it on wheels. Having prepared the wheel I would use U-Pol Acid 8 etch primer and then your 2k paint on top. If you do need highbuild I would still put the etch primer on first.

Epoxy primer would no doubt work in place of etch primer but I have not yet used it myself.

I was under the impression that you should only use an etch primer whem the wheel is stripped down to bare metal, which is what i do. And then i use the high build primer.

So do you suggest that i only use an etch/epoxy primer?

 

[Chipper]

What's lifting, the primer off the wheel? Or is it the colour coming off the primer. If the colour's coming off the primer, praps it needs a decent scuff first, will do if the primers been on a while.
Etch on clean degreased bare metal, then hi-build sounds fine, have done that before.
Praps it's just not got warm enough to set up properly.

 

[langy]

Sorry mate what you just said don't make sense ??? You say you strip to bare metal and then use hi build primer, it won't stick properly, bare metal needs epoxy or etch, then if you want use hi build.
The nice thing about epoxy is it will go over anything.

I was under the impression that you should only use an etch primer whem the wheel is stripped down to bare metal, which is what i do. And then i use the high build primer.

So do you suggest that i only use an etch/epoxy primer?