door lower trim restoration

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gwb72tii
Posts: 725
Joined: Sep 21, 2021 4:58 PM
Location: The Great Pacific Northwest

door lower trim restoration

Post by gwb72tii »

Maeve is in need of something that restores the condition and black color of the knee height door trim.
My goal is to avoid repainting it with SEM or some other rattle can if I can help it.
There are more than a few products that advertise being able to restore the black rubber (or is it plastic) part of the trim to like new condition.
Do you have any experience using these rub on compounds, and would you recommend them?

TIA
Machtig
Posts: 267
Joined: May 14, 2009 10:44 AM
Location: Kingsland, GA

Re: door lower trim restoration

Post by Machtig »

I’ve used most of them. All are very similar and do work for a time but reapplication is needed periodically. I currently use one made by Chemical Guys. None of them get it 100% back to looking new but better than before. YMMV
jayjaya29
Posts: 203
Joined: Jul 30, 2014 12:53 AM
Location: Atlanta, GA

Re: door lower trim restoration

Post by jayjaya29 »

Forever black is essentially shoe polish dye that has worked well for me over the years and lasts a lot longer then rub on products like back to black.

https://www.amazon.com/Forever-Bumper-I ... B00FAYLPZK
stuartinmn
Posts: 9462
Joined: Feb 12, 2006 12:00 PM
Location: Minneapolis

Re: door lower trim restoration

Post by stuartinmn »

I've never tried it personally, but I've heard that careful application of heat with a heat gun can help rejuvenate the looks of black vinyl trim. Do your own research before trying this, of course.
Mike W.
Posts: 27179
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: door lower trim restoration

Post by Mike W. »

I've used a number of products over the years with little success. Some are better than others, or perhaps I should say some are worse than others, but they're all oily. I was especially disappointed in Meguiars product as I've had pretty good luck with most of their products, but not this one. Chemical Guys might be almost up into the mediocre category, but no better. Really Amour All is as good as most of them IMO. As I said, none of them I've tried last particularly long, I typically apply it after a wax job, just kind of icing on cake.

Depending on how nice you really want it, buying new is an option, it appears they're still available.

https://www.getbmwparts.com/oem-parts/b ... 1131927405

https://www.schmiedmann.com/en/cata-ol?q=51131927405#
vinceg101
Posts: 4878
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: door lower trim restoration

Post by vinceg101 »

Mike W. wrote: Oct 24, 2023 5:01 PM I've used a number of products over the years with little success. Some are better than others, or perhaps I should say some are worse than others, but they're all oily. I was especially disappointed in Meguiars product as I've had pretty good luck with most of their products, but not this one. Chemical Guys might be almost up into the mediocre category, but no better. Really Amour All is as good as most of them IMO. As I said, none of them I've tried last particularly long, I typically apply it after a wax job, just kind of icing on cake.

Depending on how nice you really want it, buying new is an option, it appears they're still available.

https://www.getbmwparts.com/oem-parts/b ... 1131927405

https://www.schmiedmann.com/en/cata-ol?q=51131927405#
This is true for the standard trim pieces although you should check with online suppliers to be sure. If you're talking about Shadowline, 2 or 3 of the components are NLA, which is the problem I encountered when I tackled this project earlier this year. For the money and the effort, if they're available and not prohibitively expensive, this is the best option for the time and effort. Swapping the pieces out is easy and the time it will take to refinish the trim pieces, treat them, keep them treated and looking new will pale in comparison to the cost for new pieces.

The problem is that most of the existing pieces are dinged, dented, scratched and/or deteriorated so you have to put in the effort to refinish them first then go about treating them. I did all this, took photos and was going to add it to my M535i restoration page but not gotten around to it yet.
First step was to thoroughly strip off all previous treatment (strong degreasers, soap, even acetone). Careful not to strip off the small silver band on the standard pieces.
Next I used both acetone and 6000 wet sandpaper to even out the surfaces.
Then start applying the treatment of your choice. For me I tested a few and landed on this stuff: Car Guys Plastic Restorer
https://www.amazon.com/dp/B071FRWWRF/?c ... _lig_dp_it

It goes on well and not too greasy, but it a topical treatment so it does have a finite application life. For mine, it was important to make the refinished parts match the new ones, so there was a bit of experimentation and redo involved; but if you aren't doing that then I would apply, buff in/off, re-apply, so on, so on a few times to work it into the rubber pieces. The goal is to make it look refreshed without it being too greasy.

The other product I usually have used on all exterior rubber parts was something not made anymore (memory fails me at the moment and the only place it is is not near here) but it is a great rubber & tire treatment. With this you will want to buff it into the rubber in successive layers.

I have been trying to apply this method to restoring the crazed rubber surfaces on the MTech rear spoiler lip with limited success (only because the damage is too great.
gwb72tii
Posts: 725
Joined: Sep 21, 2021 4:58 PM
Location: The Great Pacific Northwest

Re: door lower trim restoration

Post by gwb72tii »

The right rear trim piece is NLA, but all the other pieces are available, and total about $275 for the 5 pieces you can still buy.
I am a little surprised the pieces don’t cost more.
John in VA
Posts: 5294
Joined: Feb 12, 2006 12:00 PM
Location: Leesburg, VA

Re: door lower trim restoration

Post by John in VA »

gwb72tii wrote: Oct 24, 2023 11:43 PMThe right rear trim piece is NLA, but all the other pieces are available, and total about $275 for the 5 pieces you can still buy. I am a little surprised the pieces don’t cost more.
Just wait!
1st 5er
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Joined: Jun 13, 2008 12:15 AM
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Re: door lower trim restoration

Post by 1st 5er »

gwb72tii wrote: Oct 24, 2023 11:43 PM
I am a little surprised the pieces don’t cost more.
🤫
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