my first post new to bass building but have built 20 or so guitars I have used with great results the stewmac hotrod, LMI and allied luthiery rods the stewmac hotrod is quite bulky compared to the allied luthiery / LMI welded rod and bar types if i was to use the best double action truss rod available for bass what would the recomendation be?
I think it really depends on how thick of a neck you are looking for. Unless the neck is really thin I dont the think the stewmac rods are a problem. I'll use something like the LMI rods if I want a super thin neck but I like the more robust construction of the Stew mac rods as well. I also find the LMI rods tend to have inconsistent welds and I end up having to file away lumpy welds from a fair number of them. On the last few basses I used double action rods from Bestbassgear.com. They are inexpensive and work quite well and might be my personal favorites. I'll definitely be using them more in the future. IMO pretty much any of the "name" truss rod makers makes a quality product.
For the price and quality these are my go to. I strongly dislike the Stewmac rods. These don't require a special router bit either. Having used both of these, I am pretty comfortable saying that they are basically the same rod with different colored shrink wrap on them. http://www.bestbassgear.com/bass-truss-rod.htm http://www.grizzly.com/products/Truss-Rod-2-Way-For-Bass/H6032
You guys are probably right, I've never used the grizzly rods. One thing I forget to mention is that my choice of truss rod depends on which end of the fingerboard has the adjustment. For access at the body I like the bestbassgear/grizzly rod. It has a metal sleeve around the adjustment nut that I really like but it makes the rod thicker. At the body end of the fingerboard there is more than enough thickness to allow it. On the other hand, when I build a neck with headstock adjustment I always use the LMI rods. They are noticably smaller rods and allow me to carve that end of the neck with less trepidation.