Building high-end 'tables cheap at Home Despot II

Crem, take it as an attack if you are that defensive. YOU seemed to be saying that folks at NASA were testing the efficacy of steam cleaning vinyl records. No? If they were doing this as part of a taxpayer funded activity, I consider it a waste of money. If you are just talking about people who happen to work at NASA who are doing some sort of home testing, I'd only ask, so what? That's all.

A typical 401 runs fast without the magnetic brake, so if you remove it, you need to reduce the turntable's speed. Other than a variac which reduces torque and motor RPM (and thus motor inertia) another way to alter the speed downward so it's accurate is to CAREFULLY turn down the step on the motor pulley. You can do this with a small metalworking file as the motor and pulley spin, checking frequently to see how the speed is being affected. I'd stop when you reach around 0.3% fast. Do all this when the motor is fully warmed up; it will run slow at first when you turn it on cold (probably still within 1%) but will speed back up as it warms up.

Since the motor will be spinning at close to 1800 rpm as you work on it, the end result will be perfectly concentric.

I'd recommend buying a replacement pulley from one of the vendors on E*** selling new ones, grinding it down, and keeping your original in a safe place.

Thanks for the replies guys.

Ebay it is - maybe I'll try Loricraft too. GP49 - this is a replacement pulley - I have the parts for Imbabi's power supply but never built it because I was bummed out by the shipping damage described. DHL has not been very nice to me.

Yes Jean, I read the opinions where the disk is considered necessary to get the full Garrard PRAT.

Leisual, be careful about getting solvent on the motor windings - if you melt the insulation the coil will probably short.

Mike

Has anyone tried to use plaster as a material in their plynth construction? I imagine it should be a pretty dead material, but I was wondering about over-damping? So here is what I want to try - build a hollow plynth using alternate layers of maple a MDF, then fill as much of the inside as possible with plaster and burlap (to give streng to the plaster. Ideas? if I cover the bottom of the deck with a plastic bag and sink it in, then after the plaster hardens, I can remove whatever material necessary to allow for movement of the mechanism underneath the deck.

Participants in this forum may be interested in an article by Garrard chief engineer E. W. Mortimer, in the July 1967 issue of Component Technology magazine, a technical publication of the Plessey Group, which owned Garrard at the time.

Go to:

http://home.earthlink.net/~transcrubbers/id18.html