HD Roll bar. Where did I eff up?
 

Been trying to get the roll bar in for two days and finally have everything drilled, aligned, and (mostly) bolted.

So I'm trying to get the seat belt tower bolts in i.e. the ones connecting the roll bar to the top of the tower(near where the oem seatbelt bolt goes in) and I can't get it to go in at all.

I've tried both the stock bolts and the hard dog bolts and this is what they look like now.

Attachment 230398

Attachment 230399

Attachment 230400

I'm wondering if I should try to tap the threads on the seat belt tower to see if that's the issue, or if I should just drill the threads out of the car and put a bolt on the other end.

I never expected this to be the hold up. Everything else is bolted in, but not fully tightened, so the alignment should be good. It looks like it's going straight in but apparently not...
Does anyone know what size/thread that bolt is so I can tap it? I'm looking up stuff on this right now as well to figure out what it is stock.I can take the bolts with me to a hardware store tomorrow to see what they thread into.

Hard dog lists them as:

• 2 - 7/16"(11mm) X 2.25" bolts (I'm guessing they're the 20 TPI one which is the fine thread as the other option is 14 TPI)

Any advice would be appreciated! Thanks in advance.

(I cross posted this across the pond just to see what folks at mnet thought as well)

Re tap for OE bolt. Drill larger hole in the tab, get new OE bolts. Win.

If retapping doesn't work for whatever reason, is drilling out the hole and putting a nut on the other end a viable option?

7/16X20TPI. Oddly enough federal law required SAE bolt not metric.

Yeah, I actually just found a thread talking about this! Apparently they say SAE or equivalent but folks just use the SAE for the US instead for liability reasons I'm guessing.

When mine did not line up, the roll bar was too wide, so we pulled it in using a rachet strap between uprights. Yours looks too narrow, so you may need a way to jack them apart.

You will have to re-tap the hole first. Then by some means like an off-roader's jack, tighten the bolt, then remove the jack.

https://cimg0.ibsrv.net/gimg/www.mia...89e11d3910.jpg

My roll bar bolt holes had that problem, not lining up perfect. I used clamps and a strap to "bend" it enough that the bolts would go in by hand and not try to cross thread.

If you've damaged the threads out of the factory seat belt mounting hole, I would be hesitant to simply clean them up with a tap. That's going to wind up weaker than factory, and the seat belt mounts are kind of important...

Is there enough meat around them to drill out and put in a helicoil?

--Ian

From what I can see, the bolts were softer than the nut, so the bolts are what sheared and were stripped. I think the guts inside are the leftovers from the bolt threads.

In any case, I definitely think you have a point there re:safety. I'll be sure to thread an additional grade 8 nut through the other side so there are more threads there as well. Do you think that would be sufficient in this regard?
I was originally thinking of just drilling through and putting a bolt on the other side, but I think you're right that a helicoil would be far smarter than that due to the number of threads and safety aspect.

A little hard to see here, but things lined up pretty well in the final mounting spot. Unfortunately, it seems like the damage was done already...



https://cimg6.ibsrv.net/gimg/www.mia...d7c9220b84.jpg

If I still have an alignment issue (which I don't think I do), I'm guessing widening the opening on the roll bar isn't a good plan, right?

The one true standard across cars, oddly enough. Kind of nice to be able to bolt Elise seats into a Miata and have the seatbelt fasteners swap across, though.

I'm almost positive you're using the wrong bolt.. Mine don't have that little hump below the bolt head.

there should be a washer for a plastic cover (to cover the bolt) on that bolt right below it instead. I remember using them, you should have them.

Which hump are you talking about?

This is from TDR's site for HD roll bar hardware.

https://cimg4.ibsrv.net/gimg/www.mia...dfaaed91fd.jpg

Edit: I see what you're talking about now. I think I have that bolt as well and the same thing happened there too. I also just double checked the alignment and the bolt sits right on top of the threads when it's in the hole on the roll bar.

Here's the other bolt as well.

https://cimg0.ibsrv.net/gimg/www.mia...a7026631dd.jpg

Opening the hole 1/16" would be OK, I would think.

In the first pics, I suppose due to camera angle, they didn't look aligned to me.

Ah, sorry about that. In the first post I was trying to show what the threads in the seat belt tower 'nut' looked like. I had my phone at an angle between the bar and the seat belt tower to focus on the inside of it. I think the frayed edges are from the stripped bolts or so I hope.

If memory serves me right, 7/16x20TPI also just so happens to fit the spec for an M11x1.25 thread. I'm pretty sure they work interchangeably, even though they may be at the limits of each others' specs.

M11?!

From hard dogs website:

• 2 - 7/16"(11mm) X 2.25" bolts

Guessing the 11 means M11 here so even HD says it's interchangeable. Stefan's basically my miata sensei at this point so I just shut up and listen to him and do what he tells me to.

Miata Xtreme, Hard Bar Sport, M2 Sport, Hard Core Hard Top Installation Instructions

There is an M11 in ISO thread. But not in a 1.25 pitch.
M11X0.5, M11X0.75, M11X1.0, M11X1.5

I priced out new hardware because I've read that it's not really recommended to re-use the hardware on these.

I'm just going to call hard dog and get the hardware kit and order the vinyl cover with the SFI padding.

Zomggg harbor freight racing delivers! The tap worked. Haven't tested it with the bolt yet, but I went super slowly, used lubricant, and cleaned the tap out multiple times. Goes in and out smoothly now.

If only fixing this was as easy...

https://cimg2.ibsrv.net/gimg/www.mia...c832ad451b.jpg

Ugh plasti-dip :(

plasti dip comes of real easy with a pressure washer

I put clear coat on it though. I've been trying to strip atleast the clear off it. I was going to call a few car washes tomorrow afternoon to see if any of them had one available for use.

Thanks for the reminder. I'm definitely going to try that.

Also, this bar has clear coat over a thick layer of black plastidip over a layer of white rattle can paint over the original HD black paint. Soooo.... I'm going to have to strip the white paint off one way or the other, but that shouldn't be too hard.

Paint stripper? I've taken multiple layers off at once if you glop it on, let it sit for 20 minutes and then use a green scrubber pad.

Aircraft paint stripper works wonders. But bundle up. That shit will take your skin off.

Jasco 1 qt. Premium Paint and Epoxy Remover-QJBP00202 - The Home Depot

Stuff in the spray bottle is purple power. Got some of that on my hands last night by mistake and it was not fun. Double gloved today haha.

I'll give that stuff a try if the pressure washer doesn't work. The white paint comes off pretty easily with goof off. I'd have to use the harsher stripper in the drive way.

If you think purple power isn't fun I wouldn't even go near the aircraft stripper. I wash shit with bare hands in purple power. Its just slimey. The stripper will leave burns.

Oh I absolutely don't doubt that about aircraft stripper. I'm just saying that I'd definitely use gloves haha.

I'm also trying to avoid taking off the stock paint job. I bet aircraft stripper would be equally adept at removing everything!

It would. It would go to bare metal. And you need more than normal rubber gloves.

If it comes to it I'll get heavy duty gloves. I can always re-spray the bar.

I wonder if it would discolor the driveway... (rented apt)

Why didn't you take it to a powder coater? They'd blast it before coating. Or are you too frugal?

That last one. I can't see that process being less than 200-300 from what I've seen. I can't say for sure that's what the local price would be.

I could have lived with the plastidip but decided to go the paint and clear route instead. I could have just touched up the areas that got chipped during the test fitting process. Having the white coat of paint left on shouldn't negatively affect the black paint I'm going to throw over it. I think that should be pretty easy to get off though.

I'm honestly just super happy that this one actually fits in my car haha. It's also rainy here and I won't be getting the hardware from hard dog till Thursday. Figured i could waste some time and do it DIY.

Spent a silly amount of money and time standing outside in 32 degree weather using a pressure washer to no avail.

I'm starting to really regret deciding not to just touch up the few nicked spots lol.

Might try going back and spraying or soaking goo off or something into the bar at the car wash and seeing if that helps. I think whatever I had applied was pretty dry. It was really hard to take off most areas.

Try Citristrip. If that doesn't work, most hardware stores have at least 2 grades of Jasco paint stripper below aircraft strength. One of those should work. Keep in mind that HD bars are powder coated from the factory, which makes paint removal a little tougher, if you are going down to bare metal.

Plastidip is a disease. Illest to the extreme.

Tried the goof off that doesn't come in a spray can. Bought three small containers of it. It took two to get most of the plastidip off. I put it on a towel and just scrubbed away and it lifted right off. I got down to the powdercoat in some places but it was taking too long to strip the white paint off this way. Some of the dip was probably left on, but I ran out of time and needed to finish this today... so this is what it looks like now!

Krylon rust tough enamel flat black followed by semi flat/semi gloss whatever it's called.

https://cimg4.ibsrv.net/gimg/www.mia...fcedf4220c.jpg