Adding coats of paint to underbody parts

[Guest]

Hey all =) 

 

I'm looking at adding additional coats of paint to some braces and brackets before I fit them underneath the car. The rear stay brackets in particular are OEM and seem as prone to rust as the W bracket so would like to prevent that from happening. 

 

Is it just a case of roughing up the finish a bit, priming, then adding however many coats of paint as I feel like? Paint noob here. 

 

Any recommendations for paint for underbody parts? I read hammerite is not so great. 

 

Protips welcome 

[ZMANALEX]

These sort of spray on rust proofing products work well:

 

https://www.zoro.co.uk/shop/automotive/cleaners-and-polish/tsh010-black-tetrosyl-tetraschutz-shutz-body-rust-protector-1ltr/p/ZT1036141X?utm_campaign=pla-Automotive+-+&utm_source=google&utm_medium=shopping-pla&utm_keyword=ZT1036141X&istCompanyId=6aa6787b-063e-4414-802d-129f235df603&istItemId=wtqilpqpap&istBid=tztx&gclid=Cj0KCQjwn-bWBRDGARIsAPS1svuqXSHs3uJl9nPocmHPTBjAHydxGRsXuaupGFm6ucIgMxocsqHP_ikaAsB9EALw_wcB

[Guest]

Thanks Alex =) Do you know how long that stuff tends to last? 

Would it apply directly over existing paint or do I need to rough up the finish? 

[Payco]

Always considered undersealing my car but when I saw the weight it would add I chose not to do it.

[Guest]

Better the added weight than extra weight reduction from things rotting off I guess 

[ZMANALEX]

9 hours ago, Doom said:

Thanks Alex =) Do you know how long that stuff tends to last? 

Would it apply directly over existing paint or do I need to rough up the finish? 

1

It should last many years mate.

Just make sure that the surface is dry, and is flake and grease free.

I have some other stuff in the shop that we use on smaller items which might be more suitable for your cause, it is in aerosol format so no compressor or gun required, so produces a much finer spray.

Let me check out the branding when I am next over at the shop and I will grab an image for you.

 

 

[Guest]

Thank you Alex, that would be very much appreciated =) I'm fitting them on Friday; my mechanic is letting me use his workshop for free and only charging me for the stuff I can't do, so if you're over at your workshop early in the week and have a chance to let me know then I can get some delivered and start making a mess before then!  

[Guest]

46 minutes ago, Payco said:

Always considered undersealing my car but when I saw the weight it would add I chose not to do it.

Hi Payco, I've just weighed the bilt hamber stuff I have to give the underside of mine a pretty permanent treatment (2 part epoxy paint, rust converting agent, and spray wax for box seams and tubes) and it came to 5.5kg including all packaging. Once you discard the tins and aerosol cans, and some of the liquid evaporates off, you're easily looking at less than 5kg to treat the vehicle =) 

Edited April 21, 2018 by Guest
Corrected language

[Payco]

Thanks mate,useful to know.

[Guest]

1 minute ago, Payco said:

Thanks mate,useful to know.

No worries =) I imagine an all over wax type underseal is heavier than a lick of heavy duty rust inhibiting paint, so I guess that may be what you saw the weight for? This should last better, the epoxy stuff says it's suitable for long term submersion in marine environments, sounds about right for our roads 

[ZMANALEX]

This stuff is ideal for small items similar to what you are proposing to rust proof.

It takes 24 hours to cure, but works a treat.

 

[Guest]

Thanks Alex! 

 

Is that a permanent coating? I thought waxoyl was a temporary thing? 

[ZMANALEX]

Parmanent, as the Waxoyl is only an additive.

We have found that once cured, it remains flexible and will not crack or peel.

[Guest]

Great, thank you! I'll go pick some up =) Will it go over the top of smooth glossy surfaces or do I need to sand it a bit? 

[ZMANALEX]

Just follow the instructions on the tin.