Just a little FYI.
This happened to me this weekend with my NS-2A... my fretless.
The single action truss rod in the NS-2A uses a Fender-Style rod with a Philips head bolt.
If the bolt freezes, be very careful, the bolt is made of die-cast metal of all things and will tear open.
Now... if this happens, carefully try to release the tension off the truss rod and remove the bolt.
You can get a replacement bolt from
Stew-Mac or Allparts. The thread on mine appears to be 10/32. Again, Fender uses this thread standard.
That's the easy way to fix the problem. There's nothing wrong with the truss rod. It's the tension nut that broke.
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After conferring with Stuart I've decided to try and replace the entire rod with a new modern double-action rod.
The issue is that the rods for the NS-2A are 25.5" in length.
Spector uses 24" rods now and has for some time. 24" is more of a standard these days.
I found a 25" double action rod on the market and am going to see if it works.
If it does, this is a way for you to upgrade the single action rod with a more difficult tension nut to a modern double-action rod with the standard 4mm hex nut.
I'll keep you all posted on how this turns out.
Worst case I'll replace the nut and leave the existing truss rod in the neck.
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