| 11-18-2020, 08:54 PM | #111 | |
|
Private First Class
 68
Rep 171
Posts |
Quote:
Seeing/experiencing this also makes me wonder- what holds the weight of the rack? Does the bolt sit on top of the frame regardless of the two prongs? If so do I necessarily need to push the second prong back down? |
|
|
Appreciate
0
|
| 03-16-2021, 04:42 AM | #112 |
|
Enlisted Member
 
12
Rep 38
Posts
Drives: 2018 M3 Comp in Sakhir Orange
Join Date: Jun 2017
Location: Bristol, UK
|
I know it's been a few months since the last post but thought I'd throw in my 2 pence (cents) worth.
I had no real problems with this mod at all. Couple of little hitches is all. I just measured to the mid-point of the 'tab' to find the position and then drilled a small pilot hole first to check my centre. Had to adjust it slightly before drilling the main hole and it came up good. Then I could measure to the centre exactly so the other 3 were spot on. I used hand drill instead of a power tool to be slow and careful. It caught a bit now and then but did a neat job. The tip of the Forstner bit I used bottomed out in the plug before the cutters had gone all the way though so I had to grind the tip off a little to get it to go all the way. Of course, I ground too much off and it wouldn't centre for the next one! Had to buy another and grind a little less off second time. No biggie. I had no issues with the captive nuts dropping in. All stayed put. They do move about a little as they're not welded. I guess you just need to be careful not to put any vertical load on them when remove the plugs so the tabs don't bend. Dunno. It's essential to go right through the CF and the bonding compound so the bolt will sit properly onto the metal of the side panel. I drilled almost right through then just chipped out the last bit of the bonding with a small screwdriver. That way, I didn't scratch up the metal with the drill. It came up real neat, too. The Forstner bit had scored a circle that made the chips come out cleanly. I used a clear silicone sealant and forced it well in around the bolt. Then smoothed it with the old wet finger to make sure there was no way there were any gaps for water to get in. I wasn't worried about using a black material. It was never going to blend perfectly with the CF and it's invisible with the flaps down or the rack installed, anyway. I've had absolutely no issues. Water just runs off the silicone. I screw some short Allen bolts into the threads when I'm not using the rack to stop water getting to the threads and they're always spotless when I take them out. So, there you go. That was my experience of this cool mod. Thanks again to maltman for posting it. It bugged the hell out of me the first time I went to my put rack on and found no fittings. It never occurred to me that they might still be there, hidden under the panel. I just thought the CF roof meant they couldn't fit them. Weird that the M4 has them. I guess BMW just took pity on you guys 'cos there's no room for anything in the back of your cars!! Sorry, I didn't take any pics. Honestly, I thought you'd had enough! |
|
Appreciate
0
|
| 04-20-2022, 05:34 PM | #114 |
|
Captain
 
255
Rep 608
Posts |
I bought the four bolts and will do this mod soon.
As much as I like the tree frog mount and it works very well I find myself driving around so carefully. I saw a white F82 with a white roof box last summer in Barcelona, looked so cool. |
|
Appreciate
0
|
| 06-12-2022, 07:57 PM | #115 |
|
Registered
0
Rep 3
Posts |
Just did this mod this weekend to my 2016 F82 M4 and wanted to share what we learned. I had my brother help me, he's worked extensively with carbon fiber having worked in the bike industry for almost a decade.
The First and Second image attached are our measurements from the tab edges that landed us dead center on all 4 bolts. The Third image shows the hole immediately after we drilled with a high speed steel brad point bit that was 1/8th diameter. Immediately after that we used a 1/2" brad point to bore the hole out until we reached the layer of resin sitting directly on top of the bolt and barely started to see a part of the bolt, from there we used a dremel with a sanding bit (Fourth image) to widen the hole to the width of the plug (.5545 inches) and then extracted that. Once the plug was nicely extracted (T30 bit by hand, if you hear any creaking stop, put it back in and dremel a bit more of the CF around the plug) we continued to use the dremel to the width of the star bolt (Fifth image) after plugging the hole with some tape to prevent any fiber dropping in. The idea is that you want to expose just enough of the aluminum under the resin to create a platform to drop your sealant (We used permatex ultra black) onto but not so much that it pours down into the plate where the receiving piece is. After we hand threaded the bolt into place just finger tight we waited 30 mins to let the permatex expand and form a gasket. Be really careful when threading the bolt into finger tight and test before placing the material, the threads are pretty big and it feels like they want to cross thread on you. 30 minutes later we used a torque 11mm wrench to get it to 25N/M (we couldn't find a torque spec anywhere for this specific bolt). and then filled in the areas around the bolt with more permatex. I let that sit for 24 hours. I hope this helps anyone else that wants to do the mod! Waiting for my bars to come in and I'll post finished pictures with the box on... now if I could just get a 56 Nord box and one of those super nice front bumpers lol Last edited by Colorado_Koi; 06-12-2022 at 08:03 PM.. |
|
Appreciate
0
|
| 06-13-2022, 08:16 AM | #116 | |
|
Captain
255
Rep 608
Posts |
Quote:
It's off topic but did you have to remove your B pillar trim in order to be able to drop the roof liner? Thanks |
|
|
Appreciate
0
|
Post Reply |
| Bookmarks |
|
|
