Recreating Missing ZHP Front Bumper Support Brackets

[///Mark_D]

I posted about this over on E46 fanatics, but thought I'd share here as well since it's ZHP (MTech II) bumper related.

A few months ago I bought a 3.0L swapped E46 touring that had a MTech II bumper installed. It had a few cracks and some damage that needed repairing, including a broken lower support bracket on the right hand side, and completely missing lower support on the left hand side.

For those not familiar, the lower support / adapter brackets are an integrated part of the bumper cover that are the attachment point for the lower inner finder liners, and make up the gap between the bottom of the bumper and the inner fender.

The ZHP bumper is lower to the ground than the standard bumper so the adapters act as spacers to allow the ZHP bumper to mount to the standard inner fenders.

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39996&d=1695828958

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39990&d=1695827182

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39997&d=1695828969

The adapter brackets are melt-welded to the bumper as a subcomponent of the bumper itself, and are not available to buy separately, even though they each have a unique BMW part number.

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39992&d=1695827655

Left: 51117893127
Right: 51117893128

So at this point I could have just reattached the RH side bracket with some bumper repair adhesive, but I still needed to source a LH side bracket. I searched for a used one from a broken/damaged ZHP bumper, but came up empty handed. So I decided to make my own.

First, I measured and 3D modeled the RH side bracket using CAD software. Then did more measuring and checking to make sure the model matched the physical part. Once I was happy with the RH side, I mirrored it over to create the LH side.

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39991&d=1695827194

I used Xometry online 3D printing to have the parts made from Polypropylene (PP), which is the same material as the bumper cover. They were printed using HP Multi Jet Fusion for high resolution and strength.

About a week later the parts showed up in the mail.

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39994&d=1695828580

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39995&d=1695828594

And then I glued them in placed with LORD Fusor 143 structural bumper adhesive.

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40000&d=1695829364

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39998&d=1695829344

http://www.zhpmafia.com/forums/attachment.php?attachmentid=39999&d=1695829354

I'm working on a few minor improvements to the model files to make the 3D printed parts more accurately match the real parts, and to improve fit and finish. Once the updates are complete I'll be uploading the final model files for anyone to use to print their own.

I printed two sets of each LH and RH side brackets, so the price per unit was reduced vs printing a single part. With shipping cost factored in, each bracket was around $30.

[squashman702]

Nice work! Have you used the bumper adhesive previously? I have a side bracket I've attempted to repair once on my ZHP, and found a better bracket to use instead, so I need a way to adhere that to the bumper skin.

[///Mark_D]

Yeah I've used the LORD Fusor brand adhesive to repair cracks and to reattach the main bumper side bracket in place. So far it's held up well and I'm impressed with how strong and flexible it is. Before using the adhesive there is a surface modifier primer so the adhesive chemically bonds with the plastic.

Check out this Youtube video for more info. Fusor is used by the pros to repair bumpers, create/repair broken mounting tabs, etc.

https://www.youtube.com/watch?v=pwufaE3FQP8

Here are previous repairs that I've done:

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40001&d=1695831121

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40002&d=1695831131

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40003&d=1695831151

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40004&d=1695831165

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40005&d=1695831176

http://www.zhpmafia.com/forums/attachment.php?attachmentid=40006&d=1695831185

[cakM3]

Mark, if you get to the point where you can sell off sets I would be interested. I like this solution. This is good stuff :thumbsup

[///Mark_D]

Thanks! I might do another small run just to confirm fitment with the minor changes I'm making to the CAD models. The other set I ordered the first time around I sold to malapane since he was still looking as well. (http://www.zhpmafia.com/forums/showthread.php?23540-Might-anyone-have-this-part).

Did you need just one side, or both?

When I was looking into 3D printing I checked a bunch of different sites and Xometry was the least expensive. Ordering one piece per side it was like $43 each, but when ordering at least two it dropped to $29 each. They could also print using multi jet fusion (MJF) instead of the more standard FDM, which avoided having to print lots of additional support structures due to the odd shape of the parts.

I should have the models updated in a couple of days and I'll share them here.

[cakM3]

Thanks! I might do another small run just to confirm fitment with the minor changes I'm making to the CAD models. The other set I ordered the first time around I sold to malapane since he was still looking as well. (http://www.zhpmafia.com/forums/showthread.php?23540-Might-anyone-have-this-part).

Did you need just one side, or both?

When I was looking into 3D printing I checked a bunch of different sites and Xometry was the least expensive. Ordering one piece per side it was like $43 each, but when ordering at least two it dropped to $29 each. They could also print using multi jet fusion (MJF) instead of the more standard FDM, which avoided having to print lots of additional support structures due to the odd shape of the parts.

I should have the models updated in a couple of days and I'll share them here.

Mark, hit me up with a message when you're ready :thumbsup

My ZHP is a rescue so it would not surprise me if I need to do this when I take off my front bumper ... there are a lot of cosmetic issues with my car that I have been sorting thru since rescuing it ...

[TXRedDevil]

Amazing skills, Mark! Hell, I can't get my 3D printer to articulate and work lol. I gave up on it months ago out of frustration! Amazing what you can do these days w/ software and outsourcing the work out.

[///Mark_D]

I can still remember back when 3D printing was just becoming a thing, but was super expensive and limited in capability.

It still feels like magic sometimes how much the quality has gone up on the parts and the new printing technologies/materials that are available now.

[///Mark_D]

Hey so I forgot to update this thread, but I made updates to the bumper brackets to improve fit and add a little bit of extra strength to the mounting tab. I've been running the 3D printed parts for a few months now and put on around 4000 miles since then and the parts are holding up without issues.

Updated STL files for both LH and RH brackets can be found on my google drive here:

https://drive.google.com/drive/folders/1-BxfSQzWp3c5SRtGAtFRMoxnvf5c1Wjz [drive.google.com]


https://www.zhpmafia.com/forums/attachment.php?attachmentid=40228&d=1711476520

EDIT:
And is anyone else having issues seeing the images attached in my first post? I'm either not seeing them because of my browser security settings, or the links are all dead.

[slater]

Hey so I forgot to update this thread, but I made updates to the bumper brackets to improve fit and add a little bit of extra strength to the mounting tab. I've been running the 3D printed parts for a few months now and put on around 4000 miles since then and the parts are holding up without issues.

Updated STL files for both LH and RH brackets can be found on my google drive here:

https://drive.google.com/drive/folders/1-BxfSQzWp3c5SRtGAtFRMoxnvf5c1Wjz [drive.google.com]


https://www.zhpmafia.com/forums/attachment.php?attachmentid=40228&d=1711476520

EDIT:
And is anyone else having issues seeing the images attached in my first post? I'm either not seeing them because of my browser security settings, or the links are all dead.

yep, they are visible to me.

and...this is incredible, mark! amazing. i've actually been looking for a good plastic adhesive - i will check out the LORD Fusor stuff you mentioned, as i have to reattach a broken bumper mount on my son's 325Ci.

peter

[///Mark_D]

yep, they are visible to me.

and...this is incredible, mark! amazing. i've actually been looking for a good plastic adhesive - i will check out the LORD Fusor stuff you mentioned, as i have to reattach a broken bumper mount on my son's 325Ci.

peter

Cool, glad to know the pics are showing up. Must be an issue on my end.

And thanks! It was a fun project to recreate these brackets since you can't really buy them otherwise... it's kinda strange that BMW doesn't sell them separately, but I suppose it's because it's a subcomponent of the larger bumper cover.

Lord Fusor is good stuff. It's kind of expense up front because you also have to get the special applicator gun, and there is also primer spray / reinforcement mesh, if you need it. But the applicator gun can be reused over and over, and the primer spray and mesh are good for many repairs in the future.

I had to reattach the upper mount on one side of the bumper too and that also seems to be holding fine. I've scraped on a few driveway approaches and so far, so good.

[cakM3]

Did you need just one side, or both?

Mark, when you're ready I will want both sides. Thanks!! Awesome progress!!

[///Mark_D]

Mark, when you're ready I will want both sides. Thanks!! Awesome progress!!

It might be cheaper for you to just order a set directly from Xometry. They had the best prices back when I ordered last year. I don't have my own 3D printer, unfortunately.

If you download the files I posted on google drive you can upload them into their instant quote software to get a price. I had them printed with HP Multi Jet Fusion, made from Polypropylene to match the same material as the bumper.

Could also print them with ABS or Nylon material on an SLS printer, but I'm not sure about strength.

The prices Xometry quoted did go down substantially with quantities above just a single part each, so if there is anyone else interested I could potentially organize a group buy. The cost savings on the per unit price might be lost on the additional shipping cost though. Depends on how many people would be interested I guess.

Otherwise if anyone here has a 3D printer, feel free to go nuts. Over on E46 Fanatics someone printed one for himself that seemed to turn out well. He might be willing to run a few more, I just sent him a PM to see. I can pass along his info if he's interested.

[BavarianZHP]

Thanks for doing this! I need both sides as well, so these files will be helpful!!! If you were selling these, I’d be a buyer for sure.

[cakM3]

Thanks Mark :thumbsup

[///Mark_D]

I'll check the prices again on Xometry and post the latest prices and shipping cost here. Might make sense to do a group buy, and I'd be on board to buy a spare set to have on hand to help bring the cost per piece down.

The other guy on E46 fanatics said the one he printed on his own turned out OK, but the quality of his print wasn't as good as the ones from Xometry, so he wasn't really comfortable selling them.

[///Mark_D]

I uploaded the parts for a quote, qty 3 each left and right.

https://www.zhpmafia.com/forums/attachment.php?attachmentid=40230&d=1711648159


Splitting that total cost of $203.82 equally three ways would get us each a set of left and right parts for 67.94 per person, plus shipping from me to you would add 9.05 for a USPS flat rate small box for a grand total of $77.00

I also ran the quote to see what it would cost to order the parts yourselves individually, and the price per unit jumps up quite a bit. For a quantity of 1 each left and right side it would be $122.66 if you ordered direct.

https://www.zhpmafia.com/forums/attachment.php?attachmentid=40231&d=1711648628

If you guys want to do the group buy let me know and I can get them on order. We could also wait a day or two to see if anyone else wants to join in. Adding additional quantities above 3 really doesn't change the price per unit much, so the total cost would be the same for anyone else who wanted to join, $77

[prowlerflyer]

I would be in for a set.


Sent from my iPhone using Tapatalk

[///Mark_D]

So far it looks like we've got 4 people on board including myself for a spare set. Anyone else interested in getting in on a group buy?

[fredo]

I had my front bumper resprayed recently and the fitment looks like this. Will a new support bracket help in this case?

40240

[///Mark_D]

I had my front bumper resprayed recently and the fitment looks like this. Will a new support bracket help in this case?

40240

The lower brackets we've been talking about probably wouldn't be the issue in your case. I would guess that the upper bracket / guide has come loose on your bumper cover and needs to be reattached.

Or the white plastic bracket that bolts to the fender is broken.

Or when it was reassembled it may have just not been seated correctly.

When I fixed my bumper both of those upper brackets that are part of the bumper cover were loose. From the factory they are slotted into some tabs, and the tabs are melted down on top of the bracket to join the two pieces together. The fix is to use some high strength glue like 3M windo weld, or in my case I used LORD fusor.

https://www.zhpmafia.com/forums/attachment.php?attachmentid=40006&d=1695831185

https://www.zhpmafia.com/forums/attachment.php?attachmentid=40005&d=1695831176

These are the melt weld tabs shown with the upper bracket removed. They seem to be a pretty common failure point.

https://www.zhpmafia.com/forums/attachment.php?attachmentid=40004&d=1695831165

Here's what the fitment looked like before I reattached the bracket on the RH side.
https://www.zhpmafia.com/forums/attachment.php?attachmentid=40241&d=1713531191

[fredo]

Thank you for the detailed explanation. Sadly, I didn't pay attention to the fitment before the bumper was resprayed. I mentioned it to the body shop guy and he said that's the best he could do.

I will leave it as-is. The bumper looks way better than before, that's for sure.