Need source for truss rod

[JustinBehling]

What size truss rod do you use for a 21 fret, 30 inch scale bass? I was thinking I would need one between 19 and 21 inches. The problem is that I can't find a source for a double action truss rod at that size.

Am I just way off on the size? I'm still a bit new to all this so I may be just a little naive.

 

[Manton Customs]

A 21 fret 30" scale neck is approx 21" in length excluding the last fret so a 20" rod would work well. WD music sell them.

 

[Hopkins]

The Grizzly or BBG rods can be cut to length and rewelded if need be

 

[JustinBehling]

A 21 fret 30" scale neck is approx 21" in length excluding the last fret so a 20" rod would work well. WD music sell them.

Perfect! Thank you. I ordered one last night.