Magazine counterweights

TinkerV2 · by **TinkerV2** » Fri Feb 21, 2014 2:14 am

I'm working on a '64 Rowe JMB-100. The record magazine is designed to hold 100 records. On my model, it only holds 50 records for 100 selections. They recommend using counterweights in the locations where there's no records. My question is "Is it really necessary?" When I looked at the locations where the weights would go, they're evenly spaced around the magazine. It's actually set up so there is 5 records, 5 spaces, 5 records, 5 spaces, etc... It seems to me that it would be balanced with out these counterweights. Any opinions?

Jack

Rob-NYC · by **Rob-NYC** » Fri Feb 21, 2014 3:41 am

As long as they are evenly spaced it is not necessary to use weights.

FWIW: It is JBM -or simply "M".

Rob-NYC

by **ami-man** » Fri Feb 21, 2014 2:02 pm

Hello Jack,

The 1964 Model M Tropicana was a 200 selection jukebox but could be converted for 100 & 160 selection.

With the 1100, 1200 and the R-84 upwards mechanisms stripped gears can be avoided by spacing out the loading of the records in the mechanism so you do not get the wiplash effect of twenty plus records at the open part of the mechanism being scanned around.

I tend to place my hand on the side of the mechanism to take off the weight of the said records scanning, this help stripping the sprag wheel teeth.

Regards
Alan

Alan Hood
ami-man
UK

by **Ron Rich** » Fri Feb 21, 2014 6:59 pm

Hi guys,
I questioned this at one time, also--I was given, a very logical reason, by one of AMi's engineers, as to why it was necessary--
but I can't recall it now ?? I do recall him saying to use old records, if you did not have the original weights.
Ron Rich

TinkerV2 · by **TinkerV2** » Fri Feb 21, 2014 7:20 pm

Thanks for the input guys!

Rob, you're correct, it's a JBM. My fingers engaged before my brain.

I agree that because they are evenly spaced, it would still be balanced. The engineers were thinking when they layed out the magazine. Even if it were a 160 selection unit. The empty spaces are evenly placed.

Alan, I'll check out the sprag gear to make sure it's not damaged, since it's been operated without the counterweights. It's good to know that the sprag could be a weak point too.

Ron, I like the idea of using old records to fill the slots. I was thinking much more work by making weights. There's a pretty good picture in the manual. I weighed 5 records to get an idea of how heavy to make them. It seems that records vary widely on weight. Anywhere from 35gms to 60gms each, so I was confused on how heavy to actually make the weights. It's a perfect use for them thar old scratched vinyls taking up space.

Thanx again everyone!!

Jack