I am installing a strut tower brace and I am a bit concerned that my nuts may not be threaded on the strut bolts enough, although they are holding and are torqued correctly.






What do you think?

 

For me a fastner works correctly only if the nut threads are full engaged or if the fastener is a screw into metal, the threads extend at least 1/2" beyond.

 

those will be fine as we have seen many with less threads working.

 

Could you put thread locker on there? maybe a small dap of red?

 

Yup, thread locker is not a problem. I was mainly concerned that there wasn't enough threads to hold the strut in place properly if I hit some rough road.

 

I wouldn't use red unless you want to have to use a torch to heat it up if you ever need to remove it. Blue would be sufficient.

 

Some actual engineering info http://www.eng-tips.com/faqs.cfm?fid=1331

If I did the same install on my car I'd say screw it and then the next day probably go out and buy longer bolts and redo the job.

 

The NM strut bar (waiting in the garage to be installed) solves that problem with custom nuts that go down inside the top plate so there's plenty of thread engagement.

The torque spec for those is low (25 ft-lb) so maybe it's ok, but in your case I'd at a minimum use some blue thread locker while I looked for a solution like NM's.

 

I am a retired tool and die maker. As long as the bolt and nut have three full threads, they meet spec. for strength at 100%.
I am not a big fan of the large hole size on the strut brace though! The one on the forefront is not really utilizing holding power. The nut is only holding on two small surfaces and I doubt I would trust that to keep my towers flat!

 

I sent an email off to NM asking if they would fit a 2015 R60s and if they were available separately. I also noticed online that BMW strut bars seem to have the same nuts available but I have no idea if they would fit my MINI. This would be my optimal solution.

Thanks for letting me know about the three thread thing, that makes me feel better.

I agree with the large hole size and I suspect that it was designed for the type of nuts that NM engineering and BMW use on their strut bars. Now if I can just find four of those type nuts that fit my 2015 R60s I think it would solve all my (and your) concerns.

Allan

 

I don't know about the bars for 2nd Gen cars, but the 3rd Gen has different fasteners. My GT bar on my R56 had nuts like you're describing. That was an exact fit too. I suspect the extra slop in those mounting holes is so the manufacturing process doesn't have to be as exacting as would be required for a proper fit. The NM part (at least for my F56) is an exact fit. Hopefully you'll hear back from Jerry at NM soon. If they have one, I would definitely go with their bar.

 

Got in touch with Jerry, made a deal and got the nuts. These fit much better, have a good three or more threads additional to what I had before and go down into the space where there was slop to tighten things up. So far I am very pleased.

I will run these for a while as they are, checking the torque weekly, then when I am satisfied nothing is going anywhere I will put some blue on the threads and be done with it.

Aside from the nuts having to be sourced from NM, I am very pleased. The strut bar is one solid steel piece with no adjustments or attachments other than the stud bolts. I think this should be extremely stiff (the bar certainly is!) and really help the front end. So far, so good!