# Chassis clean up rust removal and seal



## FRRACER (Jun 23, 2013)

I am thinking to take on the job of removing all the old sealer from the chassis take all the arches back to bare metal and re coat them once the weather gets warmer.

Just need some info from those who have already done this

Areas such as the inner wheel arches could be taken back to bare metal. Chassis rails too as well as the lips for the sils which seem straight on my car.

So once those areas are back to bare metal would it be best to apply etch primer first and then use seam sealer to seal panel joints followed by epoxy mastic? Can stone chip be applied after on high impact areas such as when arches? Finally inject sils and box sections with clear wax. 

About the epoxy mastic whats the best way to apply? Spray or brush?


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## mambastu (Feb 13, 2002)

I've done all this on mine. I've used a number of products over the years and I've settled on the following. 

1)Scrape off all underseal/stone chip/seam sealer. Hot air gun makes it easier.

2)To remove paint/rust I use a grinder with a combination of 3M clean and strip wheels, wire brushes and coarse sanding discs. Difficult to reach areas were done with a finger sander.

3)De-grease area thoroughly with panel wipes or IPA.

4)Any remaining rust is dealt with by using a converter such as FE-123.

5) Apply two coats of Bilt Hamber Electrox which is a very high Zinc content primer.

6) Apply two coats of Bilt Hamber Epoxy mastic. I much prefer this to the rust buster Epoxy mastic. Nicer to apply.

7) Seal all seams with a good polyurethane seam sealer from a tube. Sika flex is good but plenty of other brands available from motor factors. This is much better than the crappy brushable cellulose seam sealer.

8) Apply a couple of coats of Epoxy Mastic over the seam sealer to protect it.

9) Spray FE-123 or Dinitrol RC900 (aerosol can is great) inside all box sections and let it dry.

10) Spray Bilt Hamber Dynax S50 cavity wax in all box sections

11) If you want to apply a waxy underseal over the body as a layer of extra protection then Bilt Hamber Dynax UB is black and can be used underbody and inside arches as a layer of protection against stones. Dynax UC is also available which is a clear version and that looks good over the Epoxy Mastic.

Forgot to say that the FE-123, Electrox and Epoxy Mastic can all be sprayed, brushed or rollered on but its generally recommended that these products are brushed on as then you're more likely to fill any pitted metal and seams and you'll get a thicker paint film.

If you want to do all 4 wheel arches, the whole underfloor area and all the chassis rails/box sections then you'll need the following quantities:

1 or 2 litres of FE-123
2 litres of Bilt Hamber Electrox
2 litres of Bilt Hamber Epoxy Mastic
Tube of Polyurethane sealant
Cellulose Thinners to clean brushes
3 aerosol cans of Dinitrol RC900 for chassis rails/box sections
2 aerosol cans of Bilt Hamber Dynax S50 for chassis rails/box sections
2 aerosol cans of Dynax UB/UC for the wheel arches
2 or 3 aerosol cans of Bilt Hamber Dynax UB/UC for the whole of the underfloor area.

Takes ages to do it but worth it to preserve them I think.

Before:

















After:


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## FRRACER (Jun 23, 2013)

Awesome thank you for that


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## Saifskyline (May 19, 2013)

To take all the old gunk and underseal off quickly, use a wire knot wheel on a grinder or drill. 

and as above use Epoxy Mastic its the best


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## simon tompkins (Aug 14, 2005)

great info there this should be made a sticky,as no doubt we will all be tackling this job as some time,if we intend on keeping our babys.


simon


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## ahsam421 (Apr 26, 2003)

Great info and details...time to order!


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## Zenki33 (Apr 6, 2014)

Apply RUST BULLET with a spray paint gun...that thing sticks real hard to the metal (and fingers lol)


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## Muj_GTR-R32 (Aug 16, 2016)

Looks great mate I'm getting mine done this winter too


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