Has anyone removed old RACP reinforcement plates?

[Nate047]

Hey guys, long story short: I'm gearing up to do kind of a big overhaul on my car this year, and I'm trying to figure out the best, most diligent way of doing things.

My car has BimmerWorld RACP plates which were installed DIY using the epoxy method, by the previous owner of the car back in 2018. As part of my overhaul, I'm planning on doing a top side reinforcement, and I'm trying to decide if it's worth removing the existing bottom side plates and basically double checking that things were done right, and fixing any cracks which may have developed in the interim.

What I don't really know is what the best way would be to remove the epoxy and coating the PO put on there. I know it will require heat. but how much, and by which method? Just trying to see if this is doable in my garage or not.

Thanks!

[heinzboehmer]

I've messed around with the epoxy I used for my vincebar (araldite 2014) and a regular heat gun got it hot enough to make it brittle. Expect to have to grind/wire wheel any remaining epoxy off of the chassis though.

[Nate047]

Cool. So the real question is do you guys think it's worth trying to remove them and do it all over again? Or if I do say the Vince Bar and the front gusset cups, and stop drill anything I can see while doing those, should I worry about what might be under the plates? Or am I being neurotic

[bmwfnatic]

Cool. So the real question is do you guys think it's worth trying to remove them and do it all over again? Or if I do say the Vince Bar and the front gusset cups, and stop drill anything I can see while doing those, should I worry about what might be under the plates? Or am I being neurotic

I would remove them, epoxying plates that are meant to be welded is stupid.

The weld in plates have several holes in them where you are meant to drill through the 'outer' layer of the RACP panel into the internal sections and then plug weld them together.
Assuming the plates have been just bonded on, they have effectively become absolutely useless if they're not connected to the internal sections at all.

If you insist on using epoxy again (this wasn't stated, so I don't know), then use the VinceSkinz by Vince, since those are designed to be epoxied, and the rivets replace the function of the welds connecting the internal sections.

If you aren't scared of welding or having stuff welded (you shouldn't be, but still) then go with a Redish/PSD or CMP kit.

[Nate047]

Thanks guys, yea I'm tentatively planning on doing Vince Skinz, bar, and gusset cups and doing everything with epoxy. Or, CMP plates, beams, and braces which would require welding. I don't know how to weld and I'm not trying to learn on this job. So I would see if I can get a mobile welder to come to my house I guess. Not really sure how that works or how much that would cost. It seems like both the Vince method and the CMP method are very well thought out and good solutions.

[bigjae46]

Unless you sealed the edges of the plates you might find the epoxied plates will come off pretty easy. Moisture destroys the bond which is why I would recommend at least welding anything that may see moisture or get wet. Or apply seam sealer to the edges.

[Cronenberged]

Could also maybe have someone dry ice blast/clean the under carriage or laser clean it.

[Nate047]

I didn't do the instal so I'm not sure how well it was done. The PO did a pretty bad job on a number of other tasks... That's why I'm leaning towards removing and redoing it, even though I know it's going to be a big pain in the ass.

[Lee_Enfield]

might not be too bad if it looks like it was half done.

I would try a strong putty knife/scrapper and a hammer. Focus on severating the adhesive from one of the surfaces, not trying to cut the adhesive itself. Once you get a purchase the adhesive will likely start to crack. You will absolutely have to sand the remaining adhesive off. Heat may not do to much but won't hurt anything.

I have 100 percent faith in a properly done adhesive/Rivit reinforcement as long as it was done with proper adhesive and quality structural rivits (not jb weld and home Depot pop rivits). This is the exact way certain aviation sectors do structural patches/doublers/splices. I'll be going with the rivit/adhesive kit from Vince when I do mine. I do agree these also usually have some sort of sealant around the edges. I would also try and stop drill any cracks to help prevent them from spreading.

One tool I would recommend you look into are a set of cleco's. They are clamps that you insert into the rivit holes to hold the peice in position while you rivit, also keeps the layers together to prevent voids. Seems like you can get them off Amazon for a decent price with the tool and clamps. There are other variants that do the same but I've only got experience with the clecos.

Just my thoughts on this, not an expert in structural repair by any means.

[Amos]

Personally, I would just leave it. Topside reinforcement is the most important thing, I don't think removing old plates and re-doing them "better" will do anything for you except peace of mind.

[fattycharged]

post some photos, but my initial thought would be to leave it and just do the topside as well.

[Nate047]

I don't have any photos at the moment. I'll see if I have time to get underneath the car this weekend. TBH I don't see anything wrong with them visually.