VPI JMW Jig Question


The JMW jig I got with my Classic arm has an adjustable length. How do I know if my jig is set to the proper length? You would think that VPI would make a scale on the jig for their various 10 to 10 1/2 inch arms.
testpilot
Yes, second to the Mint LP protractor. Much more precise and accurate on my VPI SSM, makes audible improvement.
Sorry for the thread hijack:

I've got a Mint LP coming in the mail (Yip shipped it this morning). Should I do anything to compensate for the thickness of the Mint LP? I see several users stating that the Mint LP is thicker than most records and some suggested raising the tonearm to compensate for this difference and then lowering it again once complete. Is this getting too nit-picky?
Mint directions tell you what to do for setup. Follow them exactly and be sure you have a 3x and a 8-10x loupe for setup. You need both. The magnifying glass they send sucks. You can find directions online too I believe, downloadable PDF, but they are sent with the Mint. It's good to read them ahead of time, many times, as there is much to absorb and you need to have a steady hand, good light, and follow procedures exactly. You start with the arm level. You can adjust arm height later following the correct order of setup. Take a look at Mike Fremer's 21st Century Vinyl DVD for setup of a VPI Scout. If you don't have it, you should. The Scout setup is pretty much just like the Classic table. Follow that, along with Yip's directions, and you'll be good to go and the table will sing sweetly.

PS What table are you mounting the arm to? Is it a non VPI table (ie, not the Classic table?) If so, you do need the correct spindle to pivot distance as Kgturner mentions above. Check directly with VPI customer service.
Is the VPI jig used only for cartridge alignment? Does anyone know the Spindle to Pivot distance for the Classic 3 arm? I emailed VPI yesterday but have not rec'd a response.
My understanding is the Classic 3 arm is the same as the old JMW-10.5i arm which has a 256mm spindle to pivot distance. However, I suggest you confirm this with VPI first.