Tool for measuring pivot to spindle distance?


My new cartridge is on its way. I am making sure I have all the necessary tools for setting up the tonearm and cartridge, and realized that I don't have a decent tool for measuring the pivot to spindle distance for the tonearm. All I have is a plastic ruler with mm measurements - not ideal to say the least!

I would love to get something like the Clearaudio Protractor or the Dennisen/Nerve Audio Protractors, but such tools are beyond my budget. Is there a less expensive alternative? For example, would a set of 12" digital calipers (with mm readings of course)work?

I see some calipers costing around $35 - great price - are they accurate enough at that price point? No doubt most of these are made in China, which may or may not be a problem.

My budget is not much - less than $50 would be ideal. Any advice would be appreciated.

Holly
oakiris

Showing 4 responses by brf

We must assume that your tonearm is properly mounted with the correct spindle to pivot distance. If so, go the Conrad Hoffman website http://conradhoffman.com/chsw.htm and download their free cartridge setup protractor. Enter your arm’s spindle to pivot distance and print out a customer arc protractor template.
I am assuming, perhaps incorrectly, that I need to move the armboard until the spindle to pivot distance matches, or gets very close to, the manufacturer's recommendations, then I can tighten down the screw to keep the armboard in place and go on to align the cartridge with a protractor.
Correct. The tonearm must be mounted with the correct S2P distance before the cartridge is mounted using an arc protractor specified for 294.1mm S2P distance.

Also, when using the caliper to measure the S2P distance, take the arm wand off and measure to base pivot point. This will eliminate the possibility of damage, plus you will create a more level measuring distance (if the spindle point and pivot point are not level, your measured S2P distance will be slightly off)