Do it myself: rebuilding Center Armrest..

[carman850]

Owning a MB is becoming funnier, repairing a MB is truly a joy.

Yesterday I started to rebuild the center armrest on my 92 400E, when I bought a car, the internal frame inside my center armrest was broken, after I knew even an aftermarket one cost 300-400USD, I decided to rebuild it by myself.

After I removed it and disassembled it, I was surprised by how easy it was, all I needed was a spanner to remove two bolts hold armrest onto the seat, except that I swear you don't need any tool to take apart the armrest.

I was preparing to tear apart the leather cover, but MB design was so smart, you just release the clip at the back of the armrest and whole leather cover just slips off, all the internal locking and releasing metal parts could be disassembled by bare hands.

Now I completely disassembled my armrest, the center plastic frame was broken into 2 pieces, only the foam holds them together, I want to glue them first then use steel belt to reinforce the frame.

My question is: what is the strongest glue to use on plastic?

Thanks.

What worked for me in the past on other plastic items is to rough up the surface on plastic pieces on both sides of the break and use fibreglass resin to bond a thin piece of metal in over the break. Make sure to go a at least a couple of inches either side for strength and make sure there is resin below and above the metal piece. It will be thicker than normal but strong. I found that epoxy did not give me the strength I needed for my plastic repair projects, neither did Krazy Glue, but the resin is superfast once activated and strong. Obtain from auto body supply store. That's my 2 cents worth

[Badinfo]

Yea, while in India (thats where my parents are from) I noticed a neat trick people do there if plastic stuff is broken. Normally glues work, but in many applications, the glue just isn't strong enough. So they basically take a few sewing needles, heat them up, and stick them into one of the broken pieces. They then apply *Insert standard Indian Crafts glue here* heat the needles that are sticking out of one of the broken pieces, and then slide the other piece into the protruding needles. This way, when the plastic hardens, its like super super glue, and the needles are reinforment for the plastic, so it wont break again. The crafts glue is just there to seal things up. Since we are in America (I make an assumption in your case) I would use some two-ton epoxy to seal things up. Its really strong, and costs about 3 bucks for a two chamber bottle that will last you years.

[jsmith]

JB Weld - really strong stuff but don't forget to use something to reinforce it with...

[carman850]

Thank you everyone, I just finished the project.

On my way home from work, as most of you suggested, I bought some 5 minutes epoxy glue (resin and hardener), the plastic frame is very hard and not flexible, epoxy is ideal for the task.

I couldn't find the flexible steel belt from our Canadian Tire hardware store, just bought some large size nylon cable ties instead, they looked strong enough, the only problem was I could only put them around the frame then pull the ends to fasten, they might not be tough enough.

I first pried the foam around the plastic frame, prepared spaces to fit in the cable ties, also prepared the cable ties to the approximate size, cleaned the gaps of broken frame with a tooth brush, then applied glue onto the gaps.

The glue hardened super fast, I had only 4 minutes to apply glue , attach cable ties and fasten them, I was lucky to make it in 3 minutes, the nodes of the cable ties hide into the foam, barely noticeable.

Let it dry for about 20 minutes, I then gave all the rotatable parts a good lubricate, just when I put the last part back, wife shouted from kitchen "Supper is ready!", it took me 1 hr.

[ebennz]

carman850

i have a different problem with my armrest, since you just had yours apart hoping you can help.

the cover is worn on the "down"side. can i either flip the cover over or remove and reverse the armrest, so that the unused side is now where i can rest my arm?

am i being clear?

thanks

peter

[carman850]

Peter,

Don't know what your model is though, at least for my 92 W124, the shapes of the up and down side are very different, the fit is very tight, I don't think it fits if you flip the cover, plus the hole on one side is much larger than the other.

The mounting mechanism is on the left of the armrest, you have no way to move it to right, you can not reverse the armrest either, unless you want point it for the rear passengers

My up side of the leather cover is also worn, just like many W124s, the decorative strips at the edge are deterioating, it's very annoying, haven't figured out a way to fix it either.

[ebennz]

carman850

thanks.

peter

As my car is a rhd the armrest is mounted onto the passenger (left side) seat. You mentioned that the pivot can't be moved, can you explain why - I would like to swap mine to the other side if possible.

Cheers
Matt.

[carman850]

Matt,

For my 92 W124, the rotating mechanism goes with the armrest, it is embedded into the plastic frame, the seat has only 2 mounting bolts to mount armrest, I'll just assume your 126 has the same armrest as my 124.

I guess in your case, RHD, you want to move the armrest to the driver's seat, you can move the mounting bolts from the seat, but the due the rotation direction of the armrest, it should be always mounted to the right side of the seat, which in your case may not have enough room and you have armrest on the door already.

If you want to mount it onto the LHS of the seat, the armrest will have to sway from horizontal position downward, you may not have enough room for this motion.

Please forgive my crappy Engilish, hope I answered your question.

Thanks Carman850 - what you are saying is that the pivot in the arm rest cannot be removed and turned around so the armrest can be moved onto the right hand side seat. If the pivot was cut off the armrest frame could it be rotated and then reattached?

[carman850]

Matt,

The pivot and it's lock/release mechanism are built into the plastic frame, the plastic frame itself is part of the lock/release mechanism, you can not just simply cut the pivot and mount it on the other side, the other side is totally occupied by the big releasing button, lock/release interconnect and 3 big springs, you have no place to re-attach the pivot, even if you attach it there, you will have to lose the lock/release function.

I would say only the craziest DIY would try that

Thanks Carman850. I just hate how the passenger puts the seat back or forward and messes with my armrest position :-)

[carman850]

Just an update, it has been a week since I rebuilt the armrest, it is strong and holds up well, maybe it's still too early to tell.

All it took me were 7$ for the glue and cable ties and a couple of hours.