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DIY Turntable Advice Needed!

Not sure that will have enough torque for this application. If I have the spec correct (big if, I can't translate the product page), the motor can handle an intertial load of .02 KgCm^2. It turns at 250 RPM. To get 33 1/3 RPM you need a 7.5 : 1 gear ratio. Since the inertial load it can handle will increas by the square of the gear ratio, that means your max inertial load is .02 x (7.5^2) or 1.125 KgCm^2. The diamiter of an LP and therefore a plater is 30.5 cm and the formula for finding the inertia of a disk is 1/2 m r^2. Using the 1.125 Kg for maximum inertial load and a platter radius of 15.25 cm to find the mass of the platter, I come up with a mass of .009675 Kg. That is an awfully light platter. (this assums I've done this math correctly.) I would assume you would want something much heavier for a turntable. My Thorens belt drive turntable has a platter mass close to 3.25~3.5 Kg.

Hope this is a correct analisys for you.

Shelly_D
Oh I didn't really thought about it! But if (and I'm sure) your calculations are right, how would it affect my TT?
If I have an heavy platter (2-3kg), would it just take more time to reach the full speed? Or it would really affect the 250RPM motor speed?
Thanks again for your time anyway, a pleasure to learn new stuff!
 
Hey Patslice
Sunbeam's suggestion is right on the mark. So much so that I'm buying this for my next TT project.
 
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