Paints and Preservatives

Briefly (and hopefully) to the point.

One of my more long term (never ending) projects involves the restoration of an old vehicle.

Rust removal and painting are covered in numerous threads here and they have provided some useful information. However I do have some specific questions however.

First - what are various opinions about the product Por15. The internet provides conflicting views. One in particular - once a container is opened and exposed to air the contents will start to harden and will continue even on resealing said container. This I have found - in my own direct experience - to be false (6 month and doing fine). So if that is false then what other miraculous properties are untrue.

Second - this product, [https://polishnparts.ie/eastwood-patina-preserver-aerosol-invisible-rust-protectant-coat/ ] - or similar. Do they do what they promise or is this even realistic.

Thanks in advance for any consideration given.

Regards.

Frank C.

Edited By Chuck Taper on 14/07/2023 11:13:44

Hi Frank,
POR-15 is a brand, not product so can't comment. On the Patina Preserver I'm dubious. Lots of buzz words but little hard data. It does say at the bottom " Clear protection lasts for approximately 12 months depending on conditions " this does not inspire confidence. If after 6 months it starts flaking off what do you do? Re-apply, strip it all off? It is also expensive.

Robert.

Judging by POR15's MSDS, its just the stuff for men who don't believe paint works properly unless it's full of dangerous chemicals!

Anyway, the film part is created by three iso-cynanates. These polymerise into a plastic layer. Polymerisation is inhibited in the can by a bunch of toxic solvents, which evaporate when the stuff is painted on.

The paint will always polymerise eventually, even if the can is never opened. Opening the can accelerates polymerisation, how fast depends on the circumstances.

Paint rarely goes from good to bad quickly, which makes old and previously opened paint risky.

Fresh paint spreads, sticks and hardens to specification, so the ideal way of using it is to prepare the surface carefully, open a new can, and apply all of it immediately.

Unused Paint 'goes off' slowly and subtly, by not spreading, sticking or hardening to specification, and it's less able to cope with indifferent preparation. For a long time old paint looks OK, but isn't - it's gradually degrading.

Up to a point, old paint can be used satisfactorily for many ordinary purposes. Might last 7 years instead of 10, which doesn't matter at all when wifey insists on redecorating every 5 years. Or need three coats instead of two, develop runs, spread unevenly, and never fully harden. Small fault and disadvantages that may go unnoticed.

The risk of unsatisfactory results slowly increases as paint ages, and it's difficult to predict when it stops being 'good enough'. Some cans go off quickly, others take longer. As it's a gamble, I wouldn't advise using anything other than fresh paint when results matter.

We live in a cruel world. We can't buy a gallon of ACME Paint for sixpence, that was mixed by Master Craftsmen using only the finest secret materials, that never goes off, applies perfectly to any surface, and lasts forever. Real paint is hard work and the results are never permanent.

Dave

Indeed.

There is no such thing as a free lunch.

I wound up using some agricultural equipment stuff for the chassis which seems reasonably ok in terms of finish. I'm about to dismantle the leaf springs to clean and refinish and was wondering if any of the miracle products were worth trying.

I think will stick with tractor paint.

Regards

Frank C.

Agricultural paint is brilliant, I have used tractol for years and it’s a bu***r to get off.

Once stripped and cleaned I use regular applications of black waxoil on series land rover leaf springs.