Painting/treating rusty old car parts before reinstallation

[Bennet]

Hi Pistonheads,

I've disassembled the rear suspension on my old MG ZT-T. Most of it is being replaced but the subframe is going back on.

For the subframe, my plan is:

1. Wire brush drill attachment until it's looking a lot cleaner
2. Paint it with - something...

Is this the right plan?
What should I paint it with?

The car is an all-weather workhorse.

Or should I take it to the local body shop and get them to spray it with underseal or something?

Thanks.

[suggest_me_a_name]

Degrease

Wire wheel

Rust converter e.g. POR-15

Clean.

Panel wipe

Zinc primer

Then paint

Then dintrol

[Belle427]

Flap wheel most of the corrosion off and then paint, im currently doing some suspension arms on a car and am using rustoleum combi colour black.
The new epoxy paint systems are supposed to be very good too, I see buzzweld products recommended a lot.

[_Hoppers]

Don’t forget to remove sharps edges and casting marks for a finer finish!

[ROTELLA]

If you can get it to a sandblaster/powder coating place they'll do a far better job than you can manage yourself.
It'll leave you with an excellent surface for paint/gravitex or similar.

[eltax91]

Just off the back of my second knackered old Land Rover resto.

As someone has said - if you can take it to a sand blaster it’ll be 10x better than the flap wheel/ wire wheel.

Paint wise, I’ve had excellent results with corroless anti rust primer and glass reinforced top coat. Expensive as paint goes… but designed for marine applications and oil rigs so I’ve always found it extremely hard wearing.

[Bennet]

Thanks for all responses.

For clarity, are you suggesting I should get it sand blasted, and then also let the same place powder coat the part, such that it's then ready for reinstallation?

(Also, not sure if sand blasting will be a good option for me, because there are bushes in the subframe which I was hoping to avoid trying to remove. Especially because said bushes don't seem to be available to buy from anywhere.)

Cheers.

Edited by Bennet on Monday 1st December 15:04

[eltax91]

Bennet said:

Thanks for all responses.

For clarity, are you suggesting I should get it sand blasted, and then also let the same place powder coat the part, such that it's then ready for reinstallation?

Cheers.

I haven t done that recently. Because I found powder coated parts UNDER a car seems to start by getting a small stone chip in the powder coat and then it expands from there.

For me it s not hardy enough. Although the finish is visually much nicer.

My personal preference would be to get it blasted and then treat it myself with rust inhibiting primer and top coat of choice.

Regarding the bushes. Just tape them off and make it clear you don’t want them blasting in the vicinity

[Bennet]

Makes sense, and thanks for the advice.

[Retro_Jim]

I'm a little late to this thread but I wouldn't use POR 15 personally I found it to be brittle, that might have been me making a mistake but for parts that are underneath the car I have used a good epoxy primer (brush or spray) and then used Upol products like raptor etc.

You can get them in black or a tintable if you would prefer another colour.

I'd avoid painting anything white too - it looks great for 5 minutes!