Rusting Chasis tubes

[Robster]

Not a question, more an observation. The car was new in '98, the rear chasis tubes powder coating is peeling off. It appears to have been coated without an etch primer..and onto dirty/rusty tubing in the first place. Poor show really.

[NigelJ]

Hi Robster

 

My car is a '99 and it too was suffering from the same problems. I think the rusting is as a result of the powder coating getting chipped and then water gets in behind it and off it all goes.

 

As far as I know no primer is used in the powder coating process and indeed it may not be the best process in the first place but it is easy and looks good when new. I wire brushed off my chassis tubes and them POR15'd them which seems pretty good and I know others have done the same with good results. It likes to be applied to rusty surfaces so the preparation is easy.

 

Cheers

 

NigelJ

[CageyH]

Just make sure you don't get any on your skin.

It takes weeks to get off!

[Bricol]

I've said it before and here goes again - if you paint over a rusty surface, with anything, all you are doing is covering it up and letting it carry on hidden away . . .

 

I use a spot blaster bought from machine mart and fine, dry sand to do little spots . . . then paint over with a decent paint as mentioned. However, a couple of weeks ago, as I needed to do a larger, more rusted area, 75 quid saw a man with a BIG compressor come to my house and do it properly - in less than 5mins - worth doing if you intend keeping the car.

 

In previous life as industrial wash machine designer, when tight-fisted customers came back to us to repair a mild steel tank after 6, 7 etc year (normally originally 5mm thick) as it had rotted through, to continue the tight fistedness, most went for the speedy, quick repair . . . concrete in the bottom. However, such a repair may not work with a seven . . 😬

 

Bri

[Robster]

Hi All

 

I have recently finished building an MG Midget and got lots of bits powder coated locally. They used an etch primer and then the powder coat. More time consuming but it was what they recommended. The finish was good, and it is 'bonded' to the surface.

[Roadsport06]

Having read so much about rusting, particularly galvanic corrosion I have been going around my car with Hammerite underseal with waxoyl already in it and in the tight areas like in between footwell and chassis etc with some dinitrol. I will be interested in a few years how my car is faring in the rust dept.

[Shaun_E]

Arch now zinc phosphate prime the chassis before powder coating - this is intended to stop the rust creeping should the powder coating become chipped which is what happens on the older chassis.

 

Yellow SL #32

[Unclefester]

Powder coating is about as much use as chrome plating unless there is something substantial underneath it to resist the capillary pull of H²O once it's pinholed. Dire stuff, it became attractive to manufacturers becaus ethe labour input is less.I detest the damn process, it's all very pretty to watch and looks nice new (like chrome on steel) but stays on little longer.

 

Anyone know when Caterham started using it? Some time mid 80's is my guess, my 81 TC is in superb nick as it has a painted chassis, while the DD 91 is dropping the useless powder coating off everywhere.

 

Stupid, having to do a full resto on a car that's 15 years old while the 25 year old on about the same mileage is still fine!

 

That's progress, folks!