Hammerite / underseal

[muddymart]

After poking around the chassis and other panels with a large pointed implement, i was suprised how in good condition everything was ,i was pondering how i could smarten things up,

i was going to wire brush( on a drill of course) the complete lot down and apply smooth hammerite, as anyone done the same or used a different method without braking the bank?

many thanks

[Guardian.]

stonechip / underseal will be tons cheaper than hammerite, although in my opinion a good thick coat of hammerite is the best protection you can stick on a bit of metal.

[clbarclay]

I find knocking off as much of the rust as feasible with a wire brush and then a good thick coat of under body seal works well. The general concensios I got from kit car builders was that hamerite chips too easily and that the very best on a chassis, but no way the ceapest, was pro-15. Due to a large tub of underbody seal, I have yet to try pro-15 for my self and the locost chassis got powder coated rather than painted.

[Boggert]

Tetroseal is great stuff a bit gooey to apply but is mixed with waxoil so will give good protection. Hammerite is too brittle and when struck by a stone will chip easily and let the water in.

[Drift]

Dont put por-15 on anthy thing that sees daylight unless you paint over it as UV breaks it down and it flakes off  

I just clean and paint on waxoil  
works ok for me

[waveydavey]

Take it off and Galvanize it!

OK, a bit of a big job but you can get brush on paint loaded with Zinc, not as good as galvanizing but damn good steel protection.

I do agree with Hammerite being brittle, damn good stuff but in the right places.

[Defender]

I agree, I don't like hammerite as it is too brittle & chips too easily.
I use Frost Chassis Paint. Top of this webpage
A good coat of Waxoil over the top each year also helps.

[ben_haynes]

Waxoil or other Underseal is best and it might be an idea if you spray it on as it can be a pain to get in to all them nooks and crannys that hold the muck and water with a brush

[Dr Strangeglove]

As Wavetdayey say's, a good zinc rich primer.  I design paint finishing systems and when I got my RRC I asked one of our guy's who has managed a finishing line (he is also a chemist!).  He said in first place galvanising, in second place pre-treatment and then powder coating, and in third place painting with a good zinc-rich primer.  He suggested a two-pack zinc-rich primer as it will be much stronger due to its chemical curing.  He also noted that with the two pack they tend to have a higher zinc content!

Always make sure you read the instructions mind as some may require baking to dry and may also contain nasties an as such you may need an air fed mask!

[Dr Strangeglove]

Oops - forgot to say - always waxoil inside and out after you have coated it.