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A Simple Test

Maybe everyone is already doing this andI'm the last one to figure this out, but I've tried a simple test to determine the degree of motor noise that is transfered to the cartridge.

Find a good clean record which has a longer time between a couple of tracks and, while the record is playing between tracks, turn the motor off and then back on. You'll probably detect the disappearance and re-appearance of hum and/or rumble. Any noise remaining when the motor off will be from other areas (surface noise, bearing noise, etc.)

This has been quite useful in helping set proper belt tension (more tension= more noise) and also identify differences and problems in motors as well as quickly identifying whether a motor or belt tweek was useful in reducing noise.

It's been quieter around here lately....

Jim
jimbo3
jimbo3 OP
304 posts
 
Yes, it might eat up mylar- don't know for sure, though. In my case, the silk string rides on the platter edge, so cleaning it is easy. I haven't had a residue, yet. However, I put the belt dressing on the string and not on the pulley or platter, so there is very little to start with.
dougdeacon
3,338 posts
 
Thanks Joe. I'm not too worried about the mylar, I have a 100' roll of the stuff. But a nasty residue on my cocobolo platter? No thanks! Sounds like it would poison the cats too.

I don't have any motor noise (as you know) and it's not like I have any belt slippage either. But the improved coupling when I changed from silk thread to mylar tape was quite audible. Just thought I'd take another step toward direct linkage if possible. Where's Psychicanimal when you need him! :)

Jimbo3, sorry for the threadjacking. Whether you use dead grooves between tracks or on a test record it sounds like a good test to try.
jphii
485 posts
 
Doug,

100' roll? Where did you find it? I was going to use VHS tape for the next 2 tables, but if you can turn me on to your source, I'd rather go mylar.

I know about the no motor noise. But, this just remined me that the reason my battery power has not shown up yet is I forgot to send Chris a check. OOPS! Guess I'll have to do that on Monday.

I also lookes at a CNC router table last week at the Carolina's Wood Expo. They are made right up the road in Durham. So, I think I'm going to buy one. SO, that means I'll have the Cocobolo platter soon!
dougdeacon
3,338 posts
 
Joe,

Go to http://www.mccormicksnet.com/mccormicks/tapes.htm and see the last item on the page, Mylar streamers. That's the source Chris Brady uses and recommend. Lots of colors available to suit your designs.

So how much does a CNC router cost? I assume you have more uses for it than just making a platter (or two)?
jphii
485 posts
 
Thanks Doug.

The router is about 10 grand. I've been looking at them for about a year. I can use it for many things at the shop, especially doing cabinet work. Anything it can do for the turnatbles is just a bonus!!
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