Frankenstein Bolts-Hardtop
 

So, I'm trying to put my brother hardtop on my miata that doesn't have the Frankenstein bolts. I tried to take his off, but the stud didn't come out. Only the top part did. This confused me because i've seen other people un do theirs and the whole thing just popped right out. So, one, how do I get it out? if thats the right way to go about it, two, should I just go to lowes and buy a stud? (i went and looked earlier and couldnt find one with the correct thread pattern.) or should I just order some? Cheapest site?

tldr; I need frankenstein bolts, how to i get the stud out? where do i buy a new stud? where do i buy new Frankenstein bolts for cheap?

Thanks guys. any help is appreciated.

The stud doesn't come out. There should be a screw and a nut, the nut is the big "Frankenstein" part. Your brackets on your car should have studs in them already. Unless I have compeletly forgot how the hardtop works. I bolted mine on and never took it back off.

Well on mine all there is like a screw. but on my brothers when i tried to take the frankenstein off, just the top bell shaped part came off. the stud stayed in. What do you mean by the brackets on my car should already have studs?

This happen to me.
The top just came off and left with a screw.

the only way was getting locking pliers to undo the crew. That F*** up the screw, Replaced with some low screw head.

Originally, the stud portion was part of the frankenstein bolt, not captive to the body. It's R1-38X in this drawing:

https://www.miataturbo.net/attachmen...1&d=1360255930


This is because not all cars came with the fastening points for the hard-top. If you car was ordered without the hard-top, it might have simply come with two screws in each plate, rather than one screw and one stud/frankensetin:

https://www.miataturbo.net/attachmen...1&d=1360255930

For vehicle so equipped, the dealer would remove one R1-382 screw on each side, and replace it with the R1-38X for customers who ordered a hard-top as an accessory.

(I'm not sure why some non-hardtop cars got the 38X bolt anyway. My '92 came with 'em, despite the fact that it didn't have the side striker plates for the hardtop latch.)

That said, when I have unscrewed these in the past (such as to paint the car), the stud has always remained in place. When new, it came with some threadlocking compound already applied, such that it's not going to budge easily:

https://www.miataturbo.net/attachmen...1&d=1360256132


If you absolutely need to get it out, try the double-nut method. Go out and buy two thin hex nuts that fit the stud, and lock them together. Then use a wrench on the lower one to pull the stud out.

If that doesn't work, just go to the dealer and order two of p/n NA01-R1-38XB. Rosenthal has them for $17.13 each: REAR DECK STUD (NA01-R1-38XB) - $17.13 - NA01R138XB

You're saying the frankenstein bolt came out and left a stud sticking up? You should be able to find a couple bolts thread them on the stud, and lock them together to back the stud out?

Thanks for that, Joe. My friend has been looking for those motherfuckers for ages.