Work on my Rear Chassis Rail

[Catho]

Found some shots of the work I had to do on the rear chassis rail/leg of my Carlton GSi. Thought I'd post them for folk to look at as either a comparison to similar work done by fellow members, also a record of how bad it was under there, or simply as a rough guide for anyone needing to do this work on their own car.

Cheers.

Catho.

The rail/leg as it was, with the section to be cut out marked in yellow.


Looks evem worse looking from directly below!!


Old rot cut out




Card and final steel template I made to weld back into leg


Leg cut back to 'good' metal, inside painted with 'rust prohibiting' paint







New 'plate' pieced in to existing leg







New piece after I took the grinder to it to clean up the welds






After the leg was tidied up, I coated it with more rust prohibiting paint, a rubberised underseal, then finally a waxoyl coating before all the running gear was put back.

[man of kent]

Thats a nice job. Good for another 100k. Now stop the rust bug. Welded panels rust a lot quicker than original pressed panels. The heat breaks the rust resistance somehow and makes them more prone to rust.

My 1993 club has good sidemembers and I'm going to drill some small holes big enough for an oil can and get some oil in them. This will soak between the inner and outers and stop any rust.

[Catho]

Yeah, I buried the inner part of the leg with wax (as I did with the inner quarter panels/sills/outriggers/door bottoms etc....) Did it with a gun and long this hose (with holes at certain points along it) so I could get all the way down the panel, then drew it back. There was wax dripping out the run-off holes by the time I'd done so hopefully covered the inside of the panels as well as the outer. Did all this AFTER it had been resprayed of course.

[Jimmy]

1st class job mate. Where do you live?!!! ha ha, i got a bit of welding needing doing... 

[Catho]

Haha, God, not sure I'd remember how to weld to be honest, it was about 5/6 years ago when I did that!! Maybe it's like riding a bike....you never forget (like you never forget the pain of molten hot weld dripping onto your arm whilst welding upside down!!!  )

[flash1664]

what about the sound of the molten metal running round inside your ear!!!!!

[Catho]

Hell yeahhhhhhh.......the best way to get rid of ear wax!!! 

[24vman]

That was almost as bad as mine.

Good repair

[Catho]

Cheers, and that was just for starters!!!

[man of kent]

Yeah, I buried the inner part of the leg with wax (as I did with the inner quarter panels/sills/outriggers/door bottoms etc....) Did it with a gun and long this hose (with holes at certain points along it) so I could get all the way down the panel, then drew it back. There was wax dripping out the run-off holes by the time I'd done so hopefully covered the inside of the panels as well as the outer. Did all this AFTER it had been resprayed of course.

Mentioned this before on TC so excuse me if you have read it already. Waxoyl just seals the metal. If there is rust with water between two panels the rust will continue if there is some oxygen which is likely. To kill rust you must either kill it by chemical action or stop it starting or cut it out.

Many years ago there was a product called Dinitrol based upon the Swedish anti rust fluid. Very good product but the franchised garages did not do it properly and Dinitrol went bust. The latest product is Supertrol made by/marketed by Action Can Ltd. Only available commercially but they sold me some some years back. Its used on the oil rigs. Its similar to waxoyl but much better for 2 reasons:-
a)it doesn't wash off like Waxoyl. Waxoyl is ok for non shot blasted cavities so no good for under the wings.
b)when damaged, it creeps and reseals so is ok under the wings as it closes chips (within limits).

Non of these kills rust.

For hidden rust I use - oil. It creeps into cavities and along dirt covered surfaces. Bit mucky on the drive if you overdo it.

This info is gathered after 50 years experience and quite a few classic car rebuilds.

[Einarrson]

Great work there Catho!

I remember reading about the Dinitrol stuff or something similar. Apparently the strings of molecules are really thin so it can penetrate into the microscopic gaps in the metal keeping air and water away.

I use a phosphoric acid based thing that blackens the metal after application, then paint with Zinc182. Not that I would recommend that though.

[Catho]

Yeah, I buried the inner part of the leg with wax (as I did with the inner quarter panels/sills/outriggers/door bottoms etc....) Did it with a gun and long this hose (with holes at certain points along it) so I could get all the way down the panel, then drew it back. There was wax dripping out the run-off holes by the time I'd done so hopefully covered the inside of the panels as well as the outer. Did all this AFTER it had been resprayed of course.

Mentioned this before on TC so excuse me if you have read it already. Waxoyl just seals the metal. If there is rust with water between two panels the rust will continue if there is some oxygen which is likely. To kill rust you must either kill it by chemical action or stop it starting or cut it out.

Many years ago there was a product called Dinitrol based upon the Swedish anti rust fluid. Very good product but the franchised garages did not do it properly and Dinitrol went bust. The latest product is Supertrol made by/marketed by Action Can Ltd. Only available commercially but they sold me some some years back. Its used on the oil rigs. Its similar to waxoyl but much better for 2 reasons:-
a)it doesn't wash off like Waxoyl. Waxoyl is ok for non shot blasted cavities so no good for under the wings.
b)when damaged, it creeps and reseals so is ok under the wings as it closes chips (within limits).

Non of these kills rust.

For hidden rust I use - oil. It creeps into cavities and along dirt covered surfaces. Bit mucky on the drive if you overdo it.

This info is gathered after 50 years experience and quite a few classic car rebuilds.

Thanks for the advice MOK. When I'd stripped the car of all its running gear I spent 2 days with just the shell on axle stands and wire brushed the whole underside of the car (going through 3 wire brush drill bits and burning out x1 drill!!). All exposed metal was etch primed and any 'pitted' or 'bubbling' metal was treated with a rust cure chemical (as mentioned by Einarrson) it turned some of the metal purple/black, I then applied a rust prohibiting paint so know the whole underneath was red/brown, then applied a 'rubbery' underseal (to help stones/grit 'bounce' off instead of chipping the underseal where it would lead to water getting underneath and I'd be back to square one!) I then applied the final black waxoyl/shultz with the waterproof/oily finish by brush getting into all the recesses, then sprayed into all the places I could with warm waxoyl so it had an almost oil-like consistancy and that's it. It's inevitable that metal and water will come into contact, and I've tried to combat any chance of it attcking the car any further.....only time will now tell. For future reference however I will definitely use the oil technique you have suggested.....sounds a lot cheper than waxoyl too!! 

Cheers.

[Catho]

I also borrowed a handy little piece of kit.....a gun with a rubber tip like a plunger that shot tiny grains of sand from an attached bag (like a mini shot blaster). I used this for parts of the car which had pitted (but still good) surfaces, for example, the joint where the bottom of the C pillar joins to the rear qtr panel just inside the boot-shut. This metal was sound, but pitted and I wanted to get all the tiny particles of rust out before sealing it back up again and getting it ready for primer/paint.

[chris]

Nice work indeed, and looking inside the leg there doesnt look to be much other rust, it should last a long time.

[Catho]

Thanks Chris

it should last a long time.

Let's hope so.....