Back when I was a kid and was playing around with that original 1452....Man, that thing used to "eat" records! I mean, you couldn't put anything "good" in there, at least not if you wanted it to stay in that condition, and with this unit I want to make sure that all of the records are treated properly!
So what do I mean when I say it used to "eat" records? In this case I'm not talking about the damage that occurs from too much VTF (Vertical Tracking Force), but rather the fact that the old unit wasn't set-up and adjusted properly. Specifically, I clearly recall that Gripper Arm was not lined-up with the Record Magazine very well, and the records used to scrape along the side of the Record Trays (the "grooves" in the Magazine where the records are stored). As a kid I didn't know how to fix this (after all, I was only 5 years old or so!), but over the years I did manage to keep some of those damaged records as a reminder.
Here's an example of the damage that can occur:
Not good!
Ok, keep this in the back of your mind for a minute.....
Recall that I had all of the brightwork either re-plated or re-chromed, and that chrome adds thickness (from several posts back).
When I initially rebuilt the Gripper Mechanism (http://jimsrock-ola1452.blogspot.com/2018/06/gripper-unit-assembly.html) I ran into a little issue with the new chrome on the Gripper Arm in that it didn't quite fit over the "boss", or "centering tab" of the Gripper Housing.
Here's another shot of that:
In order to make these two parts fit snugly, not only did I have to grind down the Gripper Arm a little (the chrome piece seen here), but I also filed-down the centering tab on the housing a little.
Granted, it really looks like crap (the Gripper Arm), but since it works I figured it was "good enough" for now.
Or so I thought......
Come time to load-up a couple records and see how the new mechanism works, and wouldn't you know it- the damn Gripper Arm doesn't line-up the record with the Record Tray, which is the same issue the old unit had back when I was a kid!
(And here I thought I was "this close" (thumb and forefinger) to putting the mechanism back in the cabinet!)
Since I've already fixed this issue (I'll get to this in a minute), and because I'm having a hard time explaining this properly, I just used my spare/"parts" 1452 to record a quick video about this which I've tossed-up to Youtube. In essence, when I got lazy and filed-down that "centering tab", I created my own problem. How? As the Gripper Arm rotates, there is a part on the rear of the Gripper Arm (the Gripper Arm Reversing Cam) which uses this tab to locate and properly align the Gripper Arm to the Magazine (old video of mine showing this here: https://www.youtube.com/watch?v=Vz5OImgxOJ0).
Any excessive play between the Reversing Cam and the centering tab will result in improper alignment (new video located here: https://youtu.be/gdM0yP6t9v0 ). And as I've shown, improper alignment can damage records.
And while I don't have the Spec for this, based on my recent experience I am going to define "excessive play" as meaning anything over 0.5 mm (half millimeter) between the Reversing Cam and the centering tab on the housing.
So how did I fix this? Well, several "quick fixes" came to mind, but since most of them were short term and temporary in nature, I didn't follow through with any of them. Thankfully I have some spare parts here, so ultimately I found the Gripper Housing with the thickest "centering tab", and decided to clean it up and use it instead of the original one.
And it just so happened that the thickest "centering tab" belonged to the Gripper Housing on my "parts" unit. Which meant I had to tear it apart:
Clean it, paint it....
The new video showing the "play" in the mechanism was taken of this same unit (the parts unit), as it now has the original ("bad") Gripper Housing in it, along with all of the dirty parts that I put back on it.
From here on out, every picture of the "actual"/restored unit in this Blog shows the repainted housing that I took from this unit.
Anyway, everything lines up perfectly now!
And what about the Gripper Arm that I had filed-down? Am I going to use it?
Heck, no! Earlier this week I took an entirely different Gripper Arm (and mechanism) up to JR Custom plating (the chrome guys) in North Branch, showed them how all of this works, and explained why it is so critical that the final dimension between the two tabs is "exact". Johnny said he "got it", and that it would take them a couple weeks to re-chrome this new arm.
I told him to take his time, as I would rather have it done right, than done right now.
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