Classic cars forum & vehicle restoration.

[Miken]

I was wondering if ayone had any experience of using this product?
I have recently bought some of this stuff;
http://www.frost.co.uk/por15-prep-metal-ready-3-78-litres.html?___store=default&gclid=COTBnb6_mb0CFZShtAodx00A0g
because It is supposed to be good stuff.
I have just fabricated some new wheel arches to fit to my pre war Morris and after welding the new steel I have ground and sanded the welds. because there were a few hollow bits the disc wouldnt get into i took it to work and went over the welds with the shot blaster.
I thought it would be a good idea to treat this bare, new, sterile metal with the above product before painting.
Following the instructions I sprayed the producet on and left it for 10 minutes before washing off in clean water.
As it dried, my lovely new steel turned a horrible brown colour which looks suspiciously like rust where before there was none.
Comments please.
Thanks
Mike

[colwyn500]

I haven't used that one Mike but most of these things use Phosphoric Acid as the main chemical de-rusting agent. When the solution is fairly dilute as I guess this one is, you can get a "flash" reaction when the steel is so clean of rust and any oils that it instantly reacts with the moisture in the air.

I would dampen a very clean cloth or paper-towel with the prep solution and wipe the whole area vigorously until it goes shiny or grey. then you need to get it painted ASAP.

[petermeachem]

I used milkstone remover, phosphoric acid. Some bits went grey and some a yucky green or brown. I didn't fancy any of the colours as ok to paint so I ground the whole lot back to bare metal. Much easier than stripping the paint and I thought it would be a better base. The acid did a good job of removing rust and stopping rust reappearing for a considerable time. One wing had some condensation from the garage roof drip on it. This removed the acid coating and replaced it with rust. I know you are supposed to be ok to paint on these phosphated panels, but it seems iffy to me.
Once I have moved house and got everything sorted out so I can progress on the car a little I might be able to comment on something other than removing paint and priming. That will be nice

[goneps]

Mike,

Surely the best people to answer your query are Frosts themselves:

http://www.frost.co.uk/contact-us/

If they're half as good as the POR15 agent in NZ they'll be able to resolve your issue over the 'phone.

Richard

[gresham flyer]

If you bead blast metal give it a coat of etch primer straight away.

Then you can start filling any imperfections or larger dents etc .

I have seen bare metal after bead blasting start to rust after only I hour or so on a damp day.

If you are going to weld any of the metal after blasting put on a weld through primer.

In my mind after restoring all sorts of vintage vehicles and items for over 30 years these brush on additives are a waste of time.

Get your items bead blasted, that certainly gets rid of the rust and it is more cost effective.

You should be able to find someone locally who can carry this out.


G.f
_________________
Austin A30 / A35 Van.
Austin Devon.
Morris Minors.
Jaguars.
Rootes Cars.
MG.
Etc.



Viking Fibreline Caravan.
Cheltenham Sable
Shorts Built Vintage Caravan 1936.

[Rosco663]

Well I have to admit I was taken in by the 'Snake Oil' salesman

I have achieved far superior results with value branded phosphoric acid solutions. You must keep the parts wetted with the solution, during the treatment, until they stop fizzing then wipe off with using several passes using a clean water dampened rag. Dry thoroughly using a heat gun then prime as soon as practical.

Cheers
_________________
Rosco

[colwyn500]