Interceptor

I've read a number of posts regarding the need to properly prep a aluminum drive housing prior to painting. What concerns me is there seems to be a narrow window once the surface is bare and priming.

If the drive is sandblasted bare and not primed until possibly a week later what should be done prior to priming ? Light sanding or some form of acid etch ?

Also am I correct that real zinc chromate prime is no longer sold due to enviromental issues. If this is correct what is the best primer for use with non-epoxy paint ?
Or should I belly up and have them painted with epoxy ?

any help is appreciated,
thanks ,
ed

Roger 1

Ed;
First of all, under no circumstances would I ''sandblast'' the drives or any other assembly for that matter. Sand will migrate to places you never imagined no matter how carefull you are. Also, the sandblasting operation will ''chew'' up the aluminum a little more than you want it to. If the drive is totally disassembled and nothing but bare castings, you could start with a chemical stripper and finnish up ''glass beading''. If the drives are together, I would sand and feather the exsisting finnish just like I would prepare any surface. I would`nt worry about sripping all of the paint off if it is in good condition. Then If you are going to do it yourself, I would go to a local ''Dupont'' Jobber and follow his recomdations for the application of an ''Imron'' finnish. Keep in mind that product compatability is of utmost importance. Labor is going to be the big ticket item here even if you do it yourself. this is no time to cut corners on materials.
what I would do, is find someone in the bodyshop buisness with ''Imron'' experience and get a price on having them paint it after you do the prep work. This is a dangerous material and does require skill to apply it properly. Good luck with the project and be carefull.
Roger 1

cuda

I'd be careful with the bead blasting. I had the bottom paint bead blasted off my boat, and it really tore up the gel coat much worse than the boat that I pressure washed with a sand attachment.

Roger 1

Cuda;
No no no! Not on fibreglass. on aluminum. Next time try soda blasting. It`s done on corvettes , it removes paint but does`nt harm the glass.........Roger 1

HOUSTONPROP

we have bead blasted several lower units upon putting new skegs on for boat dealers,and no matter how well you think you have it cleaned that sand gets in places you never want it to go.just my two cents,the best is to have a good body shop prepare it and spray a good imron using a harder ,it comes out rock hard and shiney like new.

cuda

Roger, these guys said they did Vettes all the time. That's what I get for getting lazy.

Interceptor

I think I've been convinced to skip the blasting and go with the intensive sanding/feathering followed by a pro paint job.

Roger 1

Get some beer, put on some tunes, invite some friends over and make a party out of it. Sandpaper will fit anyones hands!...Roger 1

572scarab

I drink rolling rock! hell I have seen this done on T.V