Rustproofing underbody

I read an interesting article in "Car Mechanics" magazine recently. It suggests that car manufacturers these days, use stonechip instead of the traditional bitumen-based underbody seal, for underbody and hidden areas, eg lower sills, inside wheelarches.

The underneath of my car has flaking/loose underseal, and the exposed metal has surface corrosion. Over the coming weeks/months, I will be addressing this. Does anyone have experience of treating the underfloor areas in stonechip, instead of the traditional stuff?


I've included a couple of links so you can see the 2 different products. You can buy either product in aerosol cans or "Schutz" style canisters.

Underbody seal

Stonechip

Does anyone have experience of treating the underfloor areas in stonechip, instead of the traditional stuff?

 Paul ,  if you buy the latest edition of "Practical classics and Car Restorer" there is a brilliant article on underseals and rustproofing including tips etc on prevention . Worth the money , just check the mag first because i am not certain which month it is in , i was reading it in the shop !

Mine is covered with Finnegans NO1 rust primer brown 2 coats  then topped with loads of Waxoyl Schultz.

The stone chip stuff is in my doors and rear panels and spare wheel well and repaired boot area along with the bottom of the sill , now all covered with 2Pack paint

Cheers……….
 

Cheers…….

That's interesting, I've now read both articles and they are suggesting different things. I forgot to mention, the reason Car Mechanics suggested stonechip was that, while they both offer the same level of protection, the traditional stuff eventually dries out and cracks, letting water in and starting corrosion off again.

It looks like I'll have to inject my box sections with waxoil or something. So I'll wait until all the welding's done, for that one.

Paul don't buy that mag just read it on the news stand  :wink:

The article is only 2 pages long - the car a MK1 Golf !

Cheers………

chudd said

Paul don't buy that mag just read it on the news stand  :wink:

The article is only 2 pages long - the car a MK1 Golf !

Cheers………

Too late - already bought! In fact, this month's PC has a 4 page article on rust issues in general, a 3 page practical guide to it and a product review of rust converter/remover products. Its normally a bit boring, but this month's aint too bad.

Bilt Hamber stuff i reckon is teh best around - really good rust removers..

use Epoxy Mastic on floor pan as a good base.

Stonechip is not imune to cracking and and spliting after years of abuse. Worse still it can split creating a pocket that water sits in - found some areas like this on my GTI.

I've gone overboard maybe, but I stonechipped the inner archs then undersealed over the top. Main thing with undersael is good maintainence i.e. checking it and if required cleaning back and re-doing every year or two.

markwon said

Stonechip is not imune to cracking and and spliting after years of abuse. Worse still it can split creating a pocket that water sits in - found some areas like this on my GTI.

Hmm, maybe that's down to not preparing the surface before the stonechip goes on? It says you can simply scrape off loose rust and spray it on. Perhaps if the surface is well prepared, eg shiny with a wire brush wheel mounted in a grinder, it will stick better over the years?

Hmm, maybe that's down to not preparing the surface before the stonechip goes on? It says you can simply scrape off loose rust and spray it on.

Wasn't stone chip I sprayed on, was on the car when I got it. Appears to be the original VW Stone Chip/sealant stuff - so to be fair has been there 25 years :roll: . Didn't know you could just spray stone chip on. I've always rubbed back with grit etc or used it on the top of new paint/primer.

markwon said

Hmm, maybe that's down to not preparing the surface before the stonechip goes on? It says you can simply scrape off loose rust and spray it on.

Wasn't stone chip I sprayed on, was on the car when I got it. Appears to be the original VW Stone Chip/sealant stuff - so to be fair has been there 25 years :roll: . Didn't know you could just spray stone chip on. I've always rubbed back with grit etc or used it on the top of new paint/primer.

This is what I meant - its possible that it wasn't the original stuff, but remedial work by a previous owner. I am finding many areas where patch repairs have been done, but are now needing attention yet again.

i might get the magazine in question and have a look over it myself. what is on the front cover so i know which issue to look for?

ramblin said

i might get the magazine in question and have a look over it myself. what is on the front cover so i know which issue to look for?

A Mk2 Jaguar. March 2006 edition.

chudd said

Paul don't buy that mag just read it on the news stand  :wink:

The article is only 2 pages long - the car a MK1 Golf !

Cheers………

I can only recommend buying PC, I subscribe, Its a great magzine with lots of usefull tips on restoring and maintaning cars, the support for the MK1 golf is great. In the last year they've done a buyer's guide, Suspension renewel, rust proofing to name a few.

This can only help to promote the MK1 as a true classic and bolster resale values. (It also has the biggest readership of any classic car mag!)

This magazine really champions restoring classic cars and this is where the MK1 really sits, It will help you gain skills and info to return your car to it's former glory.

(I should work in there PR dept )

The copy with the rust proofing is March 2006.

(Sorry for the rant chudd, I really like the mag :wink: )

i subscribe to Retro cars just now but may also try PC

Robb can you post what issues in the last year feature Mk1 guides please?..

fancy ordering some back issues  

wolfsburger said

Robb can you post what issues in the last year feature Mk1 guides please?..

fancy ordering some back issues  

April 2005 Golf GTI ownership guide
Oct 2005 Dampers and springs
March 2006 Rustproofing.

All these articles are performed on the MK1 golf

Hope this helps

Rob  

(Sorry for the rant chudd, I really like the mag  )

Okay Rob  :cry:

I have 10 carrier bags of PC magazine in the loft , about 8 years worth  8O Its just that since i have bought and run VW machines i prefer VW related Magazines but i do agree with you its a good read and worth the ?3.50 odd for it


Cheers…….

thanks Robb..