Rockola 442 Record Pickup Problem

Hi folks, I'm making progress with my 442 now, amp is sounding great and I have a cap kit from Jason Tisdale (Vern's).

The one problem I'm focussing on now is it's failure to pickup records properly. I've oiled the gripper and that doesn't seem to be the issue. On a few selections (S1, R1, Q1), they never seem to be picked up, this happens consistently . I've tried different records in the slots, same result. In these cases the basket is not lining up with the gripper arm at all, I've made a video where you can see this here:

http://youtu.be/2P5bV2CSDu4

When I pause the operation, you can see the record below the gripper is the one supposed to be picked up, which is way off.

This problem also occurs on other random selections, but much less frequently, 1 in 20 perhaps.

This video shows how much movement there is in the basket when stopped, and gripper arm movement

http://youtu.be/AgybOwzRYhw

I think Rob suggested moving the gripper motor gear closer to the basket gear, though this seems very tricky in situ. I'm really hoping I don't have to take the mech out as it seems to be a tough job!

Any advice would be greatly appreciated, I thought it best to post the videos so you can see what I mean

Thanks
Adam

It appears to me that Rob's suggestion should be followed--merely loosen the three motor mounting bolts, and re-position the motor closer to the gear--a small amount of "backlash" IS required, but that seems excessive---. BTW--one should not attempt to check backlash as you did using one separator--too great a chance to bend it, IMHO. I would suggest that unless someone has "adjusted" the gripper arm centering, it should never need "re-adjustment".
Ron Rich

You may be on to something Doghouse! I almost always hear that scrape sound as records are put back in, now that I check for it. I have no idea what the guy i bought it from did to it, so wouldnt suprise me if he tinkered around. First thing he did was show me how to clear a jam, when it doesnt pick up "worn" records

At some point I think the basket motor has been replaced, as one of the bolts is missing! I'll have a go adjusting this too, hopefully this and the alignment will stop me having to lift the dome every 15 minutes and correct the bad placements!

Well, it seems someone HAS been messing with this adjustment. Its a bolt with a screw head cut into it, and one half of this part has been broken off!

I managed to adjust it with a small spanner, and some pliers to hold the nut in place and made some left turns. Now those problem records are picking up EVERY time, and the record scraping sound is reduced. Ill work on it some more, if its only a few making this sound it could just be bent seperators. I did also move the motor in closer, and the backlash is now reduced a little, though this alone didnt fix the pick up issues.

Will give it a nice run tonight and see if I need to fix any "jams" - Thanks for the advice as always guys

The way I deal with this sort of alignment problem is to first establish whether it is electrical (dynamic brake failure etc) or mechanical. Then determine if it is consistent. In this case; does it occur all around, or just at specific sections of the magazine.

I make several selections and stop the mech just as it detents the magazine. then operate the gripper motor by hand (there should be a knurled post at the end of the armature) slowly close the gripper and see if -both- ends of the gripper jaws are off by the same amount.

From what I can see in the video my first guess would be a slightly misaligned readout block possibly with the error compounded by excess backlash in the magazine motor coupling gears.

Bear in-mind that wear has occurred throughout the chain. While gently rocking the magazine feel the knurled post on the rear of the magazine motor's shaft. There may be excessive end-play in the armature shaft.

These machines are pretty forgiving. Most of the problems come from "Gepettos" tinkering and thinking that an adjustment is a sub for a repair.

Rob/NYC

I suggest that you should replace that missing motor bolt ASAP--That housing is not the strongest, and with a missing bolt, it is likely to "snap off" one of the remaining two "bolt holes", as it stops/starts with a "jolt"---- I have seen this happen a few times !! Ron Rich

I suppose I'd better find another bolt pretty quick! Anyone happen to know the size?

I do find the "Gepetto" term an amusing one. We dont use it here in the UK as far as I know, but I know what you mean by it

Somehow, I knew you were going to axk that bolt size--I can not recall-- Just remove one of the other ones, for a sample, as all are the same-
"Gepetto", I think, is a NY word--never heard here on the west coast. Here we mostly call a person like that a "Rube Goldburg"--but there ARE a couple of "other" words used, also----I used to know a British word for that too, but--I've forgotten it now too-- Ron Rich

Folks, nobody used Geppetto® before me. The "inspiration" came from a trip to NJ to look at Wurlitzer 3100 in early 1987.

The fellow who was selling looked just like the fictional character complete w/mustache, glasses and I spotted a little hammer right near where he had "been working on this jukebox for over a year and couldn't get it right. When you fix one thing, right then another thing blows or you get smoke or something...."

But for $50 Mr. "Geppetto" had a deal. It took 4 days to totally wash it, fix all f-ups, add a magnetic cart and preamp, etc. Three days later it was at my antique dealer, nine days later it was back in NJ at the home of a young MD and his family.

Rob

Psych: the bolts holding the motors are 1/4-20 x 1/2 flange bolts. Remember that these are inch series, 1/4 inch nominal diameter, 20 threads per inch, by 1/2 inch length. Since they go through tapped holes, you could use a slightly longer hex cap screw of the same diameter and thread pitch along with a flat washer, if flange bolts aren't to be found. I hope inch series bolts are available there, as no metric thread will assemble properly with those tapped holes.
Patrick

Well, the problem seemed resolved, but alas no....

While it seems to always pickup records correctly, I now find that some selections get put back into the wrong slot in the basket, so basically jams the record into the slot behind it. I'm going to get that bolt for the motor and try moving the motor in closer again. The "slop" in the basket seems a little worse than it was so perhaps the motor has moved. In the meantime has anyone else seen this before? I'd have thought if it can't pickup the correct record it should be able to place it back with no issues. I'll put up some video later

Once again thanks to everyone who has helped me so far

When I rock the basket I can feel the basket motor also moves with it. Could this suggest the basket motor gears are too worn?

I don't quite understand--how much "pressure" are you putting on the basket-is the motor moving on it's mounting studs, or is the motor shaft, moving ? The gears must be tight--about .003 clearance between the gears is adequate. Ron Rich

UPDATE: I found a new bolt for the motor, could only get a hex bolt but seems to work pretty well. I moved the motor gear right in against the basket gear and bolted it up all nice and tight with 3 bolts this time!

The misalignment problem seems to be resolved! Thanks Rob for the pointers, you were 100% correct about the alignment and backlash.

At present though there is virtually no "backlash", is this a bad thing? As everything works Im tempted to leave it as is, but if potentially damaging may move it back a tad!

Ron, what I meant is the I can feel the motor shaft moving as I move the basket