300SD Rust Restoration Project - Page 3 - PeachParts Mercedes-Benz Forum

JamesDean · #31 01-08-2011, 03:50 PM

Update:

First I'd like to say that Mercedes means business with their coatings. In this particular area, the undercoat is nearly 3x as thick as the steel. On top of the steel is extremely thick sound deadening and more coating. This stuff challenged the grinder wheel and forced me to employ a two wire wheels.

I tried to mask/cover up the interior of the car as best I could, it is no doubt going to need vacuumed and cleaned.

The plan:
1) weld 22ga steel to patch that upper most hole.
2) Weld 16ga steel to patch the floor area. We'll have to bend/bash the steel to the original contours.
3) Weld 16ga steel underneath to rebuild the horn support structure. With a new solid floor in place this should be considerably easier than without.
4) Coat with everything.
5) For in the cabin, I happen to have a large roll of eDead (sound deadening material) left over from my 190E projects. So I'll put that on top of all the coatings to quiet down the interior.

JamesDean · #32 01-08-2011, 05:31 PM

Update:

Welded in new metal to the passenger side fender. All by my self

lol

came out alright.

compu_85 · #33 01-08-2011, 07:17 PM

It's amazing the undercoating still fails so often, despite how hard / thick it is

-J

JamesDean · #34 01-08-2011, 07:46 PM

Most of the failures I've seen so far on this car are due to external events:

1) Rear Window seal, water/rust eating stuff from the inside out
2) Battery acid/wiper fluid/water etc eating stuff from inside out
3) Something impacting the body tube/horn support thing..

JamesDean · #35 01-09-2011, 05:34 PM

Update:

Did more work on that front horn. Replaced all the missing section with some nice strong 16ga steel. I also started the rust converter on the existing body tube metal. The metal itself is strong I beat it with a hammer and nothing came off/broke. It just has some surface rust. The rust converter should take care of that. I wasn't able to get all the way up there but I've spotted the front part of the horn that will need to be cleaned up, recoated and re-grommetted. So while I do that I think I can hit the area with converter.

After the converter, I plan:
1) hitting the seams with the USC - All Metal
2) coating the metal with some Rust Encapsulator (2-coats),
3) Extreme Chassis Black,
4) Internal areas will get the Internal Frame Coating, where externals will get the Rubberized Undercoating treatment.

Then once all the coatings are in place, a new piece of 16ga steel will replace the open hole in the floor area. It too will get its fair share of coatings:
In Cabin:

1) All-Metal on the seams
2) Rust Encapsulator
3) Extreme Chassis Black
4) eDead Sound deadening material to replace factory material

Pictures:

Zacharias · #36 01-11-2011, 05:26 PM

Quote:

Originally Posted by compu_85

It's amazing the undercoating still fails so often, despite how hard / thick it is

-J

That is precisely the problem. It's a wonderful, water-proof blanket -- from the inside out, as well as the outside in.

Unfortunately, however, it's not an indestructible blanket. So in the event that something pierces it, water starts to creep in underneath and gets nicely trapped between it and the metal.

Zacharias · #37 01-11-2011, 05:28 PM

Man you are brave. I would really, really like to do this sort of stuff but just call me Little 'cause I'm cheeken....

Thanks for all the pics. It's a great resource.

cheers

jmk · #38 01-13-2011, 05:32 PM

That brought back some bad memories of doing similar work on my '73 SLC.

No coating is perfect, and there will always be a failure eventually. Though that Mercedes undercoating is mighty tough.

You may want to renew the vinyl coating with fiberglass mesh coated with roofing tar. I've been able to apply it in such a way that it doesn't show once it gets dirty from use. It works quite well at stopping rust, and when it fails, it is easy to renew. Rubberized coatings make repairs more difficult, and I'm not convinced that they are any better than tar coatings.

JamesDean · #39 01-15-2011, 03:20 PM

Update:

Alright so the rust converter has been applied and I've double coated it and let it set for a few days:

Theres a good quantity of surface rust on other parts of this body tube. I cant get up there with the converter and other coatings so I'm just going to use the Internal Frame Coating (which says that its a combination of converter/encapsulator) on the rest as i have a long wand that attaches to the aerosol can.

Heres some pictures of the body tube, probably wont see these too often:

I also finished off the fender and put some rust encapsulator over the rocker panel. I'll probably double coat it and put the extreme chassis black on it..then maybe get some matching paint for the lower cladding and use that on top so it looks the more original.

Today's List:

1) Internal Frame Coat the body tube
2) All-Metal the welding seams inside the tube and cover up small pin-holes (probably covered by the rust converter but just to be safe)
3) Second Coat of Rust Converter on the rocker/fender
4) Weld small patch in the passenger side wheel well
5) Install Passenger side wheels and move to driver side.

Must source all missing grommets before car is allowed to be driven again...

JamesDean · #40 01-15-2011, 05:02 PM

Update:

Discovered small hole under coolant bottle, repaired. Finished all the patch work on the front wheel well and first coat of rust encapsulator on the new metal. Second coat on the rocker panel and fender. Also put the rear wheel on and lowered that part of the car.

Watching some Top Gear while waiting for the first coat of rust encapsulator to dry. Then re-assembling the entire passenger side and shifting work to the driver side. Almost done !

JamesDean · #41 01-16-2011, 12:40 AM

Update:

Finished off welding on the passenger side exterior!
Almost done with welding on the driver side front.

Have to patch a hole near the fuse box and do some patch work around the jack point.
Then its on to the last part of the car...

Also applied more internal frame coating stuff to the passenger side body tube, seems to work better than trying to spay that rust converter in there...still didnt quite get the back half as well as the front half though...

The only things remaining, welding wise, are the hole above and a few small holes in the passenger rear.

After that I'll comb over the car looking for things to weld. If nothing. Wrap up all the coatings and begin the mechanic work.

I think if I drop the driver side bearing support bracket that I'll clean up the rest of that front horn and coat the crap out of it.

JamesDean · #42 01-16-2011, 06:16 PM

Update:

Welded in a patch piece near the fuse box on the passenger side, still needs finished, has a few small pin-holes and such.

Moved to the rear area for exploration. It is substantially better condition than the other side. The seam seems to be degraded and rusted however the structural metal is all intact and solid. Most of the rocker around it as well.

The final piece in the rear driver well is this, it probably wont be a complete patch job as it extends up pretty good and seems like much of the inner fender would need to be rebuilt. I'd do this but I dont know how much of the outer fender is still there for welding.

JamesDean · #43 01-22-2011, 04:37 PM

Update:

Finished the sway bar area patches, was expanding the hole near the jack point and decided I should investigate as to why this driver sides body tube is bent upward. It looks like someone (not in the know) tried to lift the car from the body tubes.

I explored upwards to reveal some minor rusting damage. I beat on the existing steel with a hammer and it didn't budge or dent or anything. The inboard side of the tube is all intact. It wont need any welding/treatment. Just this outside area. Looks like a few pieces of 16ga welded in the shape of L's over the area should do the trick I think. Then theres a opening at the rear of the support piece, that too, will get a piece of 16 ga.

The jack point area will also need to be resealed up with some metal. 22ga will probably do the trick there as all the structural steel is intact, just the skin has come off.

I'll probably do the same exploration of the passenger side tube when this side is complete. It'll probably be the same type of repairs.

Stretch · #44 01-23-2011, 04:10 AM

Man have you been busy - it is good to see that someone else also has the habit of taking photographs as they work.

Was there a reason why you didn't take off the front wings / fenders? I found lots of surface rust on my W123 there... (I hope I didn't miss a comment regarding that earlier)

JamesDean · #45 01-23-2011, 01:39 PM

Thanks. I try to do work on this car every now and again...

I didnt have a particular reason for not taking them off. I took one off my other 126 and heres what it looked like:

I think I'll take my camera and light and poke about in the lower portion of the fender area. Maybe I'll take them off and check. We'll see. I didnt put the above pictured fender on correctly the fit is all off. Still gotta get it repainted though.