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-   -   1987 300D (Bodhi) rolling restoration (http://www.peachparts.com/shopforum/restoration-projects-long-term-builds/376275-1987-300d-bodhi-rolling-restoration.html)

BodhiBenz1987 03-12-2016 04:12 PM

1987 300D (Bodhi) rolling restoration
 
I hate to call this a project car because for the most part in pleasant months it is my daily driver. But, as anyone who's seen my posts in diesel discussion over the years know, Bodhi suffers from a lot of rust issues. Now that I've learned to weld I'm trying to address some of them so I thought I'd start a thread. Keep in mind I'm a beginner, so this is not going to be a masterclass display of skill here.
For those who don't know the backstory on this car: This is a 1987 300D that my father bought new when I was 5, and gave to me when I was in college in 2003. It is very sentimentally valuable to me, so I'm determined to keep it going. Not trying to make a Concourse example, but an attractive driver. Of course I'm also an artist and perfectionist, so I'm trying my best to make it look good.
I'll start with a bunch of pictures from my first big bunch of proper rust repairs. Last October I decided to address when I thought was a small spot of rust on the rear shock tower, as well as the crusty fender tip on the same side. It turned into a bit of bigger project than expected and I just finished it last week (in my defense, it was cold out, and I had some distractions).
I will post some of the "before" pictures now and add more when I get around to it. :)

BodhiBenz1987 03-12-2016 04:18 PM

Well, now I can't figure out how to post photos, so you'll all have to just wait on pins and needles as I sort that out. ;)

BodhiBenz1987 03-12-2016 04:54 PM

OK, hopefully I've got it now ...
Anyhow, here's the shock tower. The design of the tower made this pretty difficult to remove and replace. There are two layers to the area where the shock mounts ... a smaller, highly contoured 14-gauge piece that mounts on the inside of the larger 14-gauge section that is spot welded to the 20-gauge wheel well steel. The rust looks like a small spot, but had permeated into both 14-gauge sections as well as the outer 20 gauge.
http://i737.photobucket.com/albums/x...psic70dyco.jpg
http://i737.photobucket.com/albums/x...psu0rq8ucq.jpg
Structurally it felt strong because there was a lot of solid metal there. However, just putting a patch on would have left a lot of rust still between the two 14 gauge pieces which would have just gotten worse.
From inside:
http://i737.photobucket.com/albums/x...psvump5rbb.jpg
With some metal cut away
http://i737.photobucket.com/albums/x...&1457819629619

So, a big ugly mess. It's also designed in a manner that it's very hard to cut apart without destroying more of the area than was damaged in the first place. I cut a huge section out of Hanno's parts car, and then took it home to carefully remove the part I wanted. I decided just to remove the top portion of the shock tower panel, as the bottom half goes all the way down to the floor of the car, is enclosed on the inside by the boxed part of the panel that runs along the side of the trunk. You really have to look at it to have an idea what I'm talking about, or cut one apart. So I cut along the line right above the bracing in the trunk, and then drilled out each spot weld on the 20 gauge surrounding the top of the panel.
http://i737.photobucket.com/albums/x...&1457820480778
(to be continued ...)

BodhiBenz1987 03-19-2016 05:06 PM

Some more rust pictures from before the repairs. I also had some pretty gross rust on the edge of the fender and decided to fix that at the same time. When I got the bumper off I found more rust, and the bumper mounts on the inside of the bumper fell apart. So there was a lot of work to do.
http://i737.photobucket.com/albums/x...&1458422056251
http://i737.photobucket.com/albums/x...&1458422056251
http://i737.photobucket.com/albums/x...&1458422056251
http://i737.photobucket.com/albums/x...&1458422056251
http://i737.photobucket.com/albums/x...&1458422056251

Mike D 03-19-2016 06:03 PM

Ahh, yes. Hidden rust, the gift which keeps on giving.

BodhiBenz1987 03-19-2016 06:41 PM

Here are some photos from repairing the shock tower. Bear in mind I am a beginner welder, and this was a pretty challenging area to tackle, so this isn't really pretty. I recently discovered there are social media accounts that find people's welding efforts to repost and mock them, so I've become a little hesitant to share my less-than-perfect work. Constructive tips are always welcome though. Overall I am pretty proud of this.
I cut the patch out of a parts car, drilling out the spot welds at the top and cutting carefully across the panel so it would line up with the hole. I had to do a lot of trimming and grinding on it to get it to fit. I used a level to make sure it sat at the same angle as the original tower.

http://i737.photobucket.com/albums/x...psmo41aphb.jpg
http://i737.photobucket.com/albums/x...psuyplxegh.jpg
http://i737.photobucket.com/albums/x...ps9kjdevfm.jpg

I then cleaned more undercoating, as well as the paint off the inside, then put weld-through primer, and tacked it in place. I tried to run short beads, since this was 14-gauge and it was thick enough to do so. I ran into two problems: the paint and wax that was behind the frame inside, and inaccessible, burned. I didn't want a fire, or just to cause much heat damage to that area I couldn't get to to refinish. I also actually burned through a couple times, which I was able to fix but was not ideal. It was hard to get a copper backing on it because of the location and I think the heat buildup was just too much. If I turned down the heat, I didn't get very good penetration at other end of the bead. So, I did it in very short beads, moving back and forth. I also, having the worst lighting known to mankind, completely missed the seam a couple times, had to grind it and go over. You can see the spot that happened. Next time I will invest in better lighting for my work. The challenge here was it was hard to duplicate the conditions to practice. I practiced on scraps but when I moved to the actual piece it was totally different. Hopefully my experience will help me the next time. It does seems to have solid penetration and is very straight. And it hasn't blown off into the trunk yet, so that's promising. :P

http://i737.photobucket.com/albums/x...pswroitgon.jpg

(the ground down bit was just because that was an area I missed a bit, and burned through once, so I ground it to check for holes)

http://i737.photobucket.com/albums/x...psrttuqsae.jpg

Inside, with primer applied

http://i737.photobucket.com/albums/x...psknmjc1yy.jpg

Primered, plug welds await. The gold is weld-through primer.

http://i737.photobucket.com/albums/x...pswljyxpas.jpg

Plug welds ... the outer metal is 20 gauge, the inside 14 ... so that was hard. And they were big holes ... I kind of just laid a few tacks in each one. You can see I burned a hole in the 20 gauge on the right. I later sanded the primer back off and fixed it. Ugly but functional.

http://i737.photobucket.com/albums/x...psbdlegkt9.jpg

I made a little patch for the part of the 20 gauge at the top that had rusted out, and welded it in, completing the shock tower.

http://i737.photobucket.com/albums/x...psbvaomket.jpg

Then added POR 15 and then seam sealer. Lots of seam sealer.

http://i737.photobucket.com/albums/x...psxf8ewfk8.jpg
http://i737.photobucket.com/albums/x...psk5dqfxpk.jpg
http://i737.photobucket.com/albums/x...psllyvlip1.jpg
http://i737.photobucket.com/albums/x...psvopw5b4r.jpg

Back in place. I will add undercoat later on the outside, but want to be able to keep on eye on the weld for a while and see if it develops cracks or other failures.

http://i737.photobucket.com/albums/x...pslrtd6sdr.jpg
http://i737.photobucket.com/albums/x...ps9uzgssd2.jpg
http://i737.photobucket.com/albums/x...psghomw7t3.jpg

Mike D 03-19-2016 09:14 PM

Looks pretty decent. I warn you though, as you get better at welding, you'll go back, look at it and think,"What kind of one-armed, blind, drunken spider monkey welded THAT"? :D

Always remember the body worker's mantra, "What the welder giveth, the grinder taketh away and the filler forgiveth your sins".;)

You probably mentioned it but I missed it.

What rig are you using? Flux core or MIG? Gas type? Amp settings? Feed rate? Gauge of wire?

BodhiBenz1987 03-19-2016 09:49 PM

Quote:

Originally Posted by Mike D (Post 3582258)
Looks pretty decent. I warn you though, as you get better at welding, you'll go back, look at it and think,"What kind of one-armed, blind, drunken spider monkey welded THAT"? :D

Always remember the body worker's mantra, "What the welder giveth, the grinder taketh away and the filler forgiveth your sins".;)

You probably mentioned it but I missed it.

What rig are you using? Flux core or MIG? Gas type? Amp settings? Feed rate? Gauge of wire?

MIG, I have a Lincoln 210MP, great machine so I can't blame that. ;) 72/25 argon CO2 mix. Used .030 wire for this, to be honest I can't remember the exact settings ... I started with what it recommended (on the test pieces) and then fine tuned until I got something that seemed to work. I'm definitely still learning that part ... what to adjust when. I did take courses and actually did really well with it in those, I got good at finding the perfect settings ... but we were using plate and thicker sheet, and flat uniform pieces of it, not thinner curved bits, with varying thickness, funny edges, in the dark recesses of a wheel well. So it's kind of tough to go from thinking I was really good at something to struggling with it. Hopefully I will improve ... I think the frustrating thing is every part is so different, whatever I learned doing one thing doesn't seem to apply to the next.
That said, this is not a visible part of the car really and if it's saving the car from rusting to death, I'm way ahead of where I was a year ago. I did do a visible job on the fender which I will post in a bit. I think with grinding and filling it came out OK. I might sand it down and refill eventually, because I really didn't get it as smooth as I wanted ... again bad lighting, and I used white primer which I think made it harder to see where I missed with filler.

My rig:

http://i737.photobucket.com/albums/x...ps96xlg2r8.jpg

Mike D 03-19-2016 10:38 PM

I'll usually use the 0.30" for tacking and where I have good solid steel which will take the heat. For those curved areas where the metal has been "stress-formed" or "stretched", I switch over to 0.25".

Good quality wire is a must. Lincoln brand is all I will use. Learned THAT lesson the hard way.
http://store.lincolnelectric.com/webapp/wcs/stores/servlet/en/leesite/consumables/mild-steel/mig-wire/superarc-reg%3B-l-56-reg%3B-superarcl-56

Gas flow can be adjusted also which can help a bit.

Yeah, welding those flat or smoothly curved pieces they use in schools is a lot different then when you're sitting inside of a trunk, laying under the car or being a contortionist trying to reach that spot which is just behind the clamp which is holding your part in alignment.

BodhiBenz1987 03-19-2016 10:56 PM

Quote:

Originally Posted by Mike D (Post 3582292)
I'll usually use the 0.30" for tacking and where I have good solid steel which will take the heat. For those curved areas where the metal has been "stress-formed" or "stretched", I switch over to 0.25".

I'll give the .025 a try next time. Especially on the thinner stuff. I did OK with this but maybe it will be easier to find the right balance with smaller. I think I have Lincoln wire ... I bought it at the welding shop and I think they really sell quality stuff only ... will check the label though. Thanks for the tips.

Mölyapina 03-22-2016 12:05 AM

Just curious, are you guys meaning to type 0.30/0.25 or 0.030/0.025?

Mike D 03-22-2016 06:38 AM

Nah, we use MANLY welders! None of that sissy stuff for us.:rolleyes:

Yes, those are typo's. Should be 0.030" and 0.025". I'm used to calling it "Aught-twenty-five" or "Aught-thirty" and I forget about the decimal point placement.

Mölyapina 03-22-2016 10:13 AM

Thought that sounded like thick wire :D

remotemark 03-22-2016 02:33 PM

Bodey - what I know about welding can be written on the inside of a matchbook cover with a dull crayon, but I'm impressed. And even if you have doubts about the aesthetics of your welds, the photography is extremely good and clear. Often, with forum pictures and my own underhood/body pictures, I am uncertain what I'm looking at, but your pictures are remarkably well lit and the camera positioning is great.

BodhiBenz1987 07-04-2016 11:57 PM

So, this is no longer a rolling restoration really ... :( ... found some spring perch rust ("some") and a little in the floorboard and just decided to do everything else while it's apart. So far I haven't even finished one spring perch, having a tough time and trying to deal with a new career so I don't have as much time as I'd like. When I am done that I will do the rockers, floorboard (small area where the bracket holding up the exhaust shield goes, worst part the get to!), couple bits on the wheel well, replace front suspension, clean up the interior while it's out (redye some parts) and then probably do the A/C (yuck but while I've got the console out ...).
Here are some pics of the passenger spring perch job. It's really bad. I wouldn't likely try this is if the car weren't so special to me. I hope I'm doing this right, I think it will be strong enough but I'm worried how the alignment will end up. There was really nothing left to mark off for the new cup. I made a jig out of cardboard and it's not really working. I cut the whole area out of a parts car and then dismantled it to make the area the cup mounts to. I bought both cups from the dealer. In hindsight I probably could have used the cup from the parts car, but it turns out I was right to assume it had a little rust too (why not start fresh).

http://i737.photobucket.com/albums/x...psg5wsdzrq.jpg

It didn't look as bad as it is (especially with the spring hiding much of that inside rust) because 10 years ago when I took it to a shop for brakes, they welded in three brackets around it and apparently just welded them right over existing rust and undercoating, and covered it up with more undercoating. To be fair, it did hold up and probably would have for a while more. But it was a nightmare to get apart.

http://i737.photobucket.com/albums/x...psawz5h7qg.jpg

http://i737.photobucket.com/albums/x...pse8mpcrkc.jpg

This is not the easiest area to cut because it attached to the frame rail on the back and I didn't want to damage that. Fortunately I was able to learn how to get it off when I took the parts car chunk apart. As you can see there are some spot welds at the bottom.

http://i737.photobucket.com/albums/x...pstbc4upiq.jpg

The new piece fitted in. As you can imagine fitting this was a bear. I chose the butt weld fitment rather than a lap with plug welds because I did not want to spring to end up too far outward. I also was concerned about additional rust opportunity on a lap weld I can't put seam sealer on (backside is enclosed). I hope this is the right choice. There will be several plug welds at the bottom and two at the top, as well as the butt welds all around the piece. The cup gets plug welded in and then a couple welds along the bottom seams. Fingers crossed the alignment works out and I don't end up with a funky ride.

http://i737.photobucket.com/albums/x...psxc8uwko3.jpg

The other side was not as bad. I will replace the cup and have to replace the area behind the cup, but most of the panel is clean.

http://i737.photobucket.com/albums/x...psgzfkrdut.jpg

I will try to keep this updated, though I won't know the success of this job until I finish all the others and get it on the road. I hope it will be helpful to others eventually, as I had a hard time finding a lot about this job for the W124 since it doesn't seem like a common failure.


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