Dunking Bulkhead Door Posts in Primer

[JackIIA]

Looking for thoughts on using a general multi-purpose primer to dunk the door posts and upper bulkhead internals (similiar to what ECR does). I'm sure Mike S. uses ppg or something topshelf, but what about just using an off-the-shelf product like Home Depot's Zinnser?

The directions say it can be used on bare steel, galvanized steel, alum., etc. My plan is to dunk the bulkhead and then media blast the external areas back to bare metal, then paint with a proper automotive paint. But given how much paint is required to fill a dunking tank, I don't want to buy 5 gals of the auto specific stuff.

[Eric W S]

Looking for thoughts on using a general multi-purpose primer to dunk the door posts and upper bulkhead internals (similiar to what ECR does). I'm sure Mike S. uses ppg or something topshelf, but what about just using an off-the-shelf product like Home Depot's Zinnser?

The directions say it can be used on bare steel, galvanized steel, alum., etc. My plan is to dunk the bulkhead and then media blast the external areas back to bare metal, then paint with a proper automotive paint. But given how much paint is required to fill a dunking tank, I don't want to buy 5 gals of the auto specific stuff.

Why dunk then strip then paint?

Just strip galvanize and be done with it. Mike's claims of longevity with epoxy primer is suspect IMO...

[kevkon]

Looking for thoughts on using a general multi-purpose primer to dunk the door posts and upper bulkhead internals (similiar to what ECR does). I'm sure Mike S. uses ppg or something topshelf, but what about just using an off-the-shelf product like Home Depot's Zinnser?

The directions say it can be used on bare steel, galvanized steel, alum., etc. My plan is to dunk the bulkhead and then media blast the external areas back to bare metal, then paint with a proper automotive paint. But given how much paint is required to fill a dunking tank, I don't want to buy 5 gals of the auto specific stuff.

You would be wasting your time. First off, that's a latex primer. Latex is particular about clean surfaces. How did or could you clean those internal areas? Second, latex has a high molecular cohesion. In other words, it doesn't flow out well. Third, if it's rust your trying to prevent the best method is to provide a means for trapped moisture to escape. Even the best paints and coatings will eventually succumb if there subjected to constant moisture. Personally, I'd either have it galvanized or make sure all cavities can "breath" or vent, prime and paint what can be, then us a quality anti corrosive coating ( waxoyl, 3M, etc) to get into the cavities.

[Mercedesrover]

You would be wasting your time.

X2. That's for your kitchen. Use automotive products on automobiles.

[JackIIA]

Nixnay on the HD Stuff Then

Glad I asked, lesson learned (and big mess averted). Well, I'll probably just shoot it as best I can with automotive paint, then go with the waxoyl.

But to your points on the galv. front, have any of you actually had your bulkhead dipped? I've just assumed it was crazy expensive.

If so, what did it run you $...if you don't mind. Thanks, Jack.

[crankin]

It all depends on who is doing it. I found a company here in East TN that dunked 200 lbs. for $150.

[redmondrover]

Chemical Strip followed by galvanizing

Our bulkhead, tunnel cover, core support, new T-posts and some custom side steps are being chemically stripped right now in Portland. Pricey at $600 for the lot. Don't know what the galvanizing will run yet. That is a couple of weeks away after new footwells are welded in.

[kevkon]

Jack, you might want to explore some alternatives to plating. Modern anti-corrosive coatings have come a long way and offer some disinct advantages over zinc plating.

[Eric W S]

Glad I asked, lesson learned (and big mess averted). Well, I'll probably just shoot it as best I can with automotive paint, then go with the waxoyl.

But to your points on the galv. front, have any of you actually had your bulkhead dipped? I've just assumed it was crazy expensive.

If so, what did it run you $...if you don't mind. Thanks, Jack.

I'll tell you how much when Ike gives me the bill.

But generally it's not that expensive at all.

[Jim-ME]

What are the alternatives? Living in Maine is really limiting my realistic options.
Jim

[Bertha]

Jack, you might want to explore some alternatives to plating. Modern anti-corrosive coatings have come a long way and offer some disinct advantages over zinc plating.

Good point.
A good epoxy primer and a wax type rust proof(check out the wurth website, its the same stuff MB, BMW and Porsche use to protect their cars) will work fine and lasts indefintely. I have been using this process for many years with great results. Galving is overkill IMO and you will never be able to get a decent looking paint finish on it.

[leafsprung]

If I lived in any state that had road salt I would not consider anything but galvanizing. Paint does NOT last indefinitely. I cannot think of any advantages paint has . . . .

[Eric W S]

Galving is overkill IMO and you will never be able to get a decent looking paint finish on it.

What do base this on? The paint on my bulkhead that the PO galvanized is fine. So is the paint on the galvanized breakfast. You can't tell either piece was plated by looking at them.

Had the PO repaired the bulkhead right to begin with I would not have had to get Ike to repair another one for me.

I talked to my body guy at length. He's painted over galv and gets great results. The adhesion problem is due to cheaping out on the prep, that's it. Spend the money and you'll get great results.

Hopefully Ike will have my bulkhead back to me soon. It's at the Galv shop now. I'll post pics of the paint once done...

Galv is the only way to go. Do your own homework. I could have had just about any anti-corrosive material applied. I stuck with Galv for a reason...

[jb_]

Good point.
A good epoxy primer and a wax type rust proof(check out the wurth website, its the same stuff MB, BMW and Porsche use to protect their cars) will work fine and lasts indefintely.

I used to work in the automotive industry and the paint process that was state of the art was an electrocoat first coat after a phosphate wash.

[kevkon]

If I lived in any state that had road salt I would not consider anything but galvanizing. Paint does NOT last indefinitely. I cannot think of any advantages paint has . . . .

Actually, zinc galvanizing does not stand up particularly well over time to salt or acids I (if it did the boat guys could save a bundle on stainless) .In fact it can't be used with the new treated wood for that reason. Actually some of the modern paints do better in that regard. As Bertha and JB stated, the electrocoat primers are state of the art in corrosion resistance.
I agree with Eric that you can finish galvanized metal, but there's added prep and you had better hope it's done correctly.