Underbody rust, including beams

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Underbody rust, including beams

Postby Wilso » 12 Jan 2019, 07:27

Hi all,

I’ve just got back from 5 months away and intend to preserve my van against future rust problems. I’ve got some surface rust on the box sections of the frame and want to know what is the best method to get rid before it becomes deep?

Angle grind with a metal brush back, prime, paint (spray cans ok?) and then seal (with?)
Hammertoe rust eater, wait, prime and seal?

I intend to under seal the floor again so suggestions on the best seal would be grand.



PS I have some pictures but struggling to find the post that details how to post them in after uploading them somewhere else?
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Re: Underbody rust, including beams

Postby Michael4 » 12 Jan 2019, 08:42

For those who have an interest in sheep I use Fluid Film, it is lanolin based...

Poured into box sections, squirted wherever I can squirt and sprayed on the underneath. I bought 10 litres about ten years ago and still have half left, use it on the boat too.

I'm new to t25s but it worked on old Austins and Citroens which are quite famous for their crumbling.

It is has an ability to creep into seams and never seems to dry.

A bit messy (like sheep) but makes the whole thing a much easier job.
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Re: Underbody rust, including beams

Postby Dubworth » 14 Jan 2019, 09:38

I'd wire brush everything down thats showing surface rust, paint Vactan on affected, then once dry use stone chip paint, or use something for underbody protection from the likes of Bilt-Hamber or Dinitrol. For box sections I'm a big fan of Dinitrol ML, can get it in aerosol form and use the extra long hose attachment to spray it in, it's quite searching so will run into areas then set like a waxy layer.
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Re: Underbody rust, including beams

Postby ZsZ » 14 Jan 2019, 11:19

+1 on the Fluidfilm, altough now I use Carplan Waxoyl with good results on surface rust
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Re: Underbody rust, including beams

Postby adie89 » 15 Jan 2019, 20:28

Gold plated solution
Strip back with wire brush - if needed cut out and weld in fresh metal
1. Etch primer to adhere to the metal
2. Epoxy primer - it’s sealed unlike regular primer which absorbs water
3. Seam seal with PU sealer
4. Chipguard to reduce chipping through to metal
5. Colour coat to seal the surface
6. Underbody spray like unterbotenschutz over the top. This will stay softer and flexible and increase resistance to knocks, moisture and salt.
Inside frame rails clean out and product of choice

Before resorting to rattle cans if you have no spray facility you can buy the better, two part, products from your paint factor and brush it on.

Before 1 get the underside hot zinc sprayed. V expensive I bet though
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Re: Underbody rust, including beams

Postby mhowood » 04 Apr 2019, 20:05

Great to find this thread - was just about to ask the same questions. Thanks!

When I got my T25 a few years ago, I was complemented by the garage, after it's yearly services, on what good condition the undercarriage was in. I could blush!
Then at last year's MOT it's suddenly falling to bits! :shock: Cue: 2 grands worth of welding work and another grands worth of parts. :cry:

I'll be investing in some ramps and some Frost Extreme Chassis Black and Waxoyl < hope I got those right. :wink:
No idea what I'm doing but presuming coat everything that isn't a nut, bolt, or moving.

Also found this thread >
Under body paint/protection https://forum.club8090.co.uk/viewtopic.php?f=38&t=166259&start=0&hilit=Waxoyl
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