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Discussion Starter #1 (Edited)
The passenger side front bolts of my targa top won't thread in and after closer inspection it appears that the previous owner attempted to "fill" the threads after stripping them and then retap new threads. However, it was clearly amateur hour as they actually ripped the nut through its carrier and now the nut spins freely and still has no threads.

I decided the targa is a goner anyway if I can't fix this, it's no good without being able to tighten the two front bolts. So I did what any self respecting supra owner would do- brought it to a buddy's machine shop and starting tearing it apart. I cut out the plate containing the nut and carrier and this is what I found:



As you can see the "female" thread that you bolt your targa into is a square nut with a circular flange held by a rectangular carrier. Those two "bolts" surrounding it are only for the manufacturing process while the piece is secured in place. So you see that over-torquing your targa not only runs the risk of stripping the threads, but you can also tear that nut right through its carrier as what happened here.

So we cut out the side of the carrier, removed the nut, drilled through it to fit in a bushing expecting to tap it to m8x1.0 as that appeared to match the threads. Well.... that didn't work. If I had searched this before I would have found this old thread with Stu Hagen's resposne on the thread pitch of the targa:

http://www.supraforums.com/forum/showthread.php?447905-Targa-bolt-thread-pitch

Stu Hagen said:
I finally found out it isnt anything normal. It is a eccentric spiral thread very similar to seat belt bolts. The are designed for *speed*, or less turns per inch so you don't have to turn as much to lock. I was able to revitalize mine 1 thread at a time. The bolt can be bought cheap from Toyota. But if you bugger up the female threads, there arnt many options except to healy arc it. You wont be able to succesfully re-tap it.
So now my last resort here is to either:

Have a tap machined to match the threads
Remove the other nut and have it replicated on the CNC
or buy a new top
or ... ?

Thoughts? Not sure if anyone has had the "nuts" to cut open their targa top before so I'm hoping this is some new information that may help lead to a reasonable process to repair our targa threads...
 

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Cheap way out of your issue, get a tap made, then weld your damaged nut up and retap it.sell the tap on here.
Unless you can have a new nut made on the cnc mill cheap.
You could always go ghetto, cut some thread clearing slots in one of your bolts and use it as a tap. new bolts are easy to get.
 

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Discussion Starter #3
Cheap way out of your issue, get a tap made, then weld your damaged nut up and retap it.sell the tap on here.
Unless you can have a new nut made on the cnc mill cheap.
You could always go ghetto, cut some thread clearing slots in one of your bolts and use it as a tap. new bolts are easy to get.
Hah that's funny, making a tap out of a new bolt is exactly what I was coming on here to post :) We're going to try it and see if it works. I'm going to document the process so it's hopefully repeatable if it works
 

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What I ended up doing was buying a wrecked Supra's targa top (it was pretty mangled), but its plates were in decent shape. I cut them out, cut my busted ones out of mine and installed the good ones into mine.

And I still haven't had a chance yet, but the plans next is to take it to a machine shop and have the cut out I did repaired.

There may be some value in someone taking their busted-ass plate (I would be happy to donate mine for the cause) and sending it off to a machine shop to have them make new plates so we can all start repairing our targas once and for all without dropping ~$1k on new ones not including paint.
 

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Well welcome to targa nut problem, it seems the only nut that everyone has a problem with is the drivers side nut. Same here did not want to cut anything in the roof, so i took my bolt to a production tool retail store to buy a tap for the nut.
I told the many people in the store that this bolt is spiral cut and after about hr. they figured it out,. That to order the tap, cost was $ 8.00. Taped the bolt myself and never looked back.
Here is the part number of the tap i used: M8X1.0 HSG D5: USA 1210P31S
Hopes this helps, Mike
 

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On a side note, replacing my bolts up front helped with my front targa rattle issues. They insert underneath the front headliner and are easy to install.
63260-14040 and 63250-14030
 

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Well welcome to targa nut problem, it seems the only nut that everyone has a problem with is the drivers side nut. Same here did not want to cut anything in the roof, so i took my bolt to a production tool retail store to buy a tap for the nut.
I told the many people in the store that this bolt is spiral cut and after about hr. they figured it out,. That to order the tap, cost was $ 8.00. Taped the bolt myself and never looked back.
Here is the part number of the tap i used: M8X1.0 HSG D5: USA 1210P31S
Hopes this helps, Mike
So that tap allowed you to properly tighten the targa bolt? It doesn't get lose after driven at all? I need to repair my CF targa.

If so, where did you get it for $8 ???

B
 

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Answers to post # 9, yes after taping the nut the bolt tightened right up and i have not had a problem with it coming loose, Toyota still sells the bolt assembly but not the nut
You have to make sure the bolt is not stripped and the tap is to re thread the nut, sorry for the confusion
I bought the tap at a tool and production retail out let, here in the Cleveland Area , pretty sure there are other outlets around the country
 
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