What primer to use

[rob love]

I'll have to call hogwash on the myth's of vehicle life during war. Perhaps the life was limited on the front lines, but for every vehicle on the fornt line there would be many many more in the lesser echelons. I cannot say I have seen any signs of lesser quality on a MV due to short life expectancy. Otherwise they would have invented the Iltis 40 years sooner.

[Private_collector]

WW2 paints might very well have had lead in the product, which would assist in protecting the substrate. Remember hearing of primer called 'Red Lead'? It was all the rage in 30s to early 60s, and the name speaks for itself. I'm not sure if that used on military vehicles, but in those days they encouraged the men to smoke too, so workplace health & safety not such a great concern as it is now.

I always use single pack primers, and always start with a light but complete coat of etch primer, for excellent adhesion and protection. Etch is only good on bare metal, so I should say that I always have things sandblasted to begin with. Nothing can hide from the sandblasters gun. Bare metal MUST be sealed as soon as possible, and neither etch nor primer/filler is protected from rain or condensation, so also MUST be kept out of the weather. Be careful using etch or any type. It can contain harmful fumes that damage the lungs. In fact, best avoiding ALL paint fumes, so be sure to wear a mask atall times. I finish coat with Protec Barrier enamel with hardener additive chucked in for good measure. Not actually 2-pack, but does have some of the same properties. My primers on the other hand, are always acrylic. You can paint enamel or Poly paints over acrylic, but not the other way around......ever. If body filler is used, as it invariably will be somewhere, prime once body filler is sanded to completion, then apply several coats of spray putty. Once again, I use acrylics there. If using full-on 2-pack, a combined undercoat/spray putty can be used (2-pack) but in long term restoration process, I would advise against it. If left for weeks or longer, it can get extremely hard, and will then be like sanding granite! Some are worse than others, but I can't say which are the hard ones, so you roll the dice there. In the good ole days we deliberately induced that hardness, by leaving a resto vehicle under primer for a number of weeks, and then did a thorough dry sand with glass paper on a long body file. You sure worked up a sweat, but got rifle straight panels (if sanded correctly). Then the priming would be done again, and painted to completion about a week later. Ah, the good ole days!

Now, how weather-proof are flat paints across the various types........., that's a whole other can of worms!

[Lynn Eades]

Good helpful post Tony. Thanks.

[Stew Robertson]

I find this conversation very interesting about military primers
Of all the vehicles I have worked on and sandblasted over the years I have never seen any primer on the vehicles direct from the factories
Just my conclusion and not saying that I do not use primer on a restoration

[Jacques Reed]

Perhaps sandblasting takes off all the paint before any levels can be exposed.

I have only used sandblasting on the chassis due to its size and preferred using a caustic soda and water bath to remove paint on all the other steel parts of my vehicle. This was then followed up with molasses and water immersion for rust removal. It is a slow process but thorough, and more gentle on sheet metal parts.

I can assure you as the levels of khaki/green/sand whatever paint came off after the caustic bath, the last remaining paint to be water blasted off the bare steel was either red or grey primer.

Cheers,

[Jacques Reed]

I have been using the generic term "red primer" in this thread. The actual colour of the primer I have seen is more a reddish brown.

Red lead primer was banned even in my early days at sea in the 70's but seafarers still called any primer "red lead" for many years thereafter. It was a more red colour compared to the reddish brown primer I have seen on my vehicle.

Doesn't prove vehicle paint didn't contain lead but obviously they were differently formulated paints.

[Jacques Reed]

Should have added this to an earlier posting.

Here is my roof after coming out of the caustic bath and first pressure wash.

Remains of "red primer" can be seen at bare metal level.

It took another dunking to remove all the primer.

Sandblasting would leave fine scratches in the sheet metal which many people like as they feel it give a good key for the primer. Again, personal preferences, but I prefer not to have the fine scratches and use Wattyl Super etch on the bare metal after the molasses bath and a wipe of metal prep followed by either Wattyl or Wagon Paints primer.

Cheers,