Fidelity Research FR-54 Tonearm. ANTI-SKATE???

Elliot, there is no direct relationship between tracking force and the weight of the anti skate bob. I do believe there was an add on weight that threaded into the bob. At any rate, set up your cartridge and tonearm. When you place the needle in the run out area between the grooves the tone arm should drift very slowly toward the spindle. If it starts drifting out ward you have too much anti skate for the tracking force and you will have to figure out a way to lighten the bob or replace it with a lighter one. The other option is the increase the tracking force to the upper limit the cartridge is specified for and see if you can get the right drift. If the tone arm drifts quickly toward the spindle you will need to add weight which you can do with 3M double sided mounting tape and any piece of heavy metal such as a nut that matches the diameter of the bob. 
This is not an exact science. As long as you get that slow drift towards the spindle you will be fine. If you want to be more exact you will need a test record with ant skate adjustment bands like the Hi Fi News test record.
The last option if the bob is too heavy is to get a cartridge that tracks at a heavier force. My guess is that the arm was tuned for the usual Japanese MC cartridge tracking at 2 to 2.5 grams. 

Elliot, thinking about it, I would not grind that weight down. I would just make a new anti skate bob with some light fishing line and lead fishing weights. Lead is very soft and easy to trim. 

Mike

You are confirming my belief, it's pulling out 2.5g.

Well, it sounds darn good 1.5g down/2.5g out, but I don't have any experience with playing Mono LP with Mono Cartridges*; This Cartridge; This Arm.

To add weight is easy. Bottom of weight is threaded. Optional weights were probably available back when ..

various length screws would add variations of extra weight. Any screw/ combo can be weighed easily enough.. I read weight has m6 threads, needs to be verified.
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The purpose is to play MONO records, for now I am sticking with 1.5g down.

a. remove weight, let stylus 'ride' the inner wall with 1.5g

b. leave weight, let stylus 'ride' outer wall +1g

c. make 1.5g weight as you suggest (I'll try that first)

d. grind weight down to 1.5g. (can add to that if needed one way or another)


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* No experience with Mono Cartridge, Except to instantly know using dedicated Mono Cartridge is clearly better than playing Mono LP with Stereo Cartridge as I used to do, in Stereo Mode or most often via Fisher or McIntosh Mono mode switches. I was happily surprised how much better on some, not all old LPs. Thanks to the thread here.

 The force with which the anti-skate weight is pulling outward on the tone arm is related not merely  to the weight in grams of the AS weight itself. It’s also dependent upon the distance of the connection between the weight and the arm wand from the pivot point. it’s a lever in principle. So if you can get out your old geometry text you can figure out how much AS force is actually pulling on your arm. And you don’t want so much as a 1.5g AS force for a 1.5g VTF. Much less will usually do.

To get you started, an AS device creates a class 3 lever. Where the tonearm is the lever, the pivot is the fulcrum, and the cantilever is the load.  See here: https://en.wikipedia.org/wiki/Lever
That's if the AS force is applied to the arm wand.  In some cases, the AS force is applied to the short arm that holds the counterweight, to the rear of the pivot, and the AS force pulls the short arm inward.  In that case, we have a Class 1 lever.