Classic cars forum & vehicle restoration.

[Uncle Joe]

When you ask for advice on this forum, and recieve it, do you use it?

Bet this is a controversial question...

UJ

[admin]

I read & take note of posts made by all the contributors on here, like the info I pick up from magazines etc, some is relevant, some I agree with, some I don't - ie it all goes into the mix between my ears and definitely influences me on occasion! especially the first hand experiences about things I've not yet dabbled with myself, such as painting


Rick

[buzzy bee]

Hi

I am simmilar to rick, I will get as many oppinions as I can and then make a decision as best as I can, I like the moto, "it can go two ways!"

Cheers

Dave

[Old-Nail]

I'll bear the good advice in mind... and then ignore it sometimes!

An example would be the use of POR chassis black which has been recommended on various forums, but as with everything in the UK if a dry day suddenly and unexpectedly occurs, and there are no local POR stockists - Hammerite it is then!

[Uncle Joe]

...er...Old-Nail...you do know that you are supposed to use both Hammerite and POR15 in moist conditions, dont you?

Anyway, theres a better product than both of these on the market, and by God its British...(I think)... makes you proud!

UJ

[Charles]

Don't know about hammerite, but if using POR15 the metal needs to be bone dry, the only advantage of a moist atmosphere is it will speed up curing, ...certainly not essential.

[Uncle Joe]

Charles: According to a reply from the people at POR a few weeks ago, it will NOT cure CORRECTLY in dry conditions. This is also the same answer that I got from Bill Hirsch, who manufacture a stuff called Miracle Paint.

So therefore I am really only assuming that the same applies to Hammerite, based on my assumption that it is similar. However, when I asked them this question (along with some others) they didn't even have the decency to reply.

UJ

[Old-Nail]

My understanding of POR is as above, I'm told it cures in damp weather.

However, my reference to having a dry day was for the actual application of the stuff, being as I have long since lost the will to be underneath a car in the pouring rain!

[Charles]

POR15is a polyurethane based paint with a high solid content, the moisture in the air is the catalyst that cures it. The reason the manufactures highlight this fact is to stop pro’s from baking it on in an oven as they would most paints. We used to use it after doing small welding jobs, normally a couple a week.

You would have to have exceptional weather conditions to not have enough moisture in the air for the paint not to cure; those of you who run dehumidifiers will know the volume of water they produce even in “dry” conditions. Incidentally we would see the same cars back year after year and I don’t recall seeing any faults with the paint we had applied.

If there were a DIY restoration book on applying paint to cars chapter 1 page 1 would talk about clean dry panels prior to painting being a must. I know it is not always easy in a DIY environment, but you could do far worse than run a hairdryer over what ever you are about to paint, I don’t mean put the paint on when its still hot but get it totally dry.

If you trap moisture in say a seam with POR or any similar paint; it stays there and you can guess what happens. Believe me I have had to fail cars because of this, and I have a lot of sympathy for their owners who though they were doing the right thing, now faced with a potentially big job to rectify. Trust me if you can pick a time pick one when we have had several dry days in a row to use these products, there will be enough moisture in the air for them to cure!

The other classic mistake I’d see was people using these products on corroded but still solid metal; they had followed the instructions and got all the loose stuff off etc, however in many cases the metal is corroding from the other side via pin holes, so you are not achieving anything.

I once had a really upset chap in the MOT bay; we failed his car on a corroded exhaust, he had fitted a new exhaust himself a few years prior to this and before fitting it cleaned all the silver paint off, treated the metal with phosphoric acid, and coated with a tough heat resistant paint, he carefully fitted it and checked underneath the car every couple of months, what he didn’t realised is that exhausts rust from the inside!
I am quite passionate about preventing corrosion, being the MOT grim reaper was not something I enjoyed, be it either the student who was trying to keep the car running on a shoe string or the 30 year old car that had rotted beyond the point of viable restoration. Most cars can be kept running and safely with a minimum outlay and tools until they corrode, then it’s a different ball game.

There is no magic product to cure corrosion after its set in, but there are many good products which can prevent it, or stop it progressing if applied correctly.
If you can blast clean back to bright metal do it, if it’s something like a door where you would struggle to blast the inside there are firms who can chemically dip them; it removes any sealants and corrosion all you are left with is the sound steel. These current dip concoctions I’m told were developed in the 90’s to service the petro-chemical industry north sea maintenance requirements, they are sophisticated products and will not attack solid steel like some of their predecessors and then get paint on straight away even if they need welding, far easier to remove the paint prior to welding than remove the fresh corrsion.
Charles

[Uncle Joe]

Charles, have a look at the topic 'Rust Preventative Paint' and see if you can guess which the paints are that I received info on. Post a reply there, I'll enjoy the discussion, as I'm sure you will!

UJ