Garrard AT6 Advice?

Hello:

I am new to the forum but have very much appreciated the information I have found in previous posts.

I have an early Garrard AT6 MkII (1963, I believe) that came as part of a KLH Model 11 suitcase hi-fi I picked up. Following the advise on this forum, and the service and instruction manuals I got online, I have cleaned it up pretty well, including performing the cure for "Garrard Syndrome" posted by Record-Changer, and the extra lubrication advice posted by by MattTech, both found on this thread - viewtopic.php?f=19&t=1016. I used Phonolube were grease was called for, and turbine oil for were oil was called for.

However I have two other issues that are causing me some headache. First, it appears that the platter is rotating somewhat unevenly (vertically oscillating about 2-3 mm while rotating). I am concerned that geared sleeve on the underside of the platter that slips over the record spindle assembly may be bent in relation to the platter, and that there may be nothing that can be done. Has anyone else come across this problem, and is there any remedy?

Also, I noticed that the turntable was slow to get up to speed, to the extent that when a 78 record dropped, it would only reach 78 rpm until several seconds after the newly dropped record began playing. Also, the turntable did not reliably spin at the 16 rpm setting. I have a both a new idler wheel, and the original (which was in good shape, and which I treated with rubber rejuvenator). I made sure both the idler wheel and the motor pulley were free of grease or oil and tried oiling the idler wheel bearing with turbine oil, but to no avail. The idler wheel just would not spin as freely as I thought it should. I then tried to slightly reduce the size of the idler wheel axel by sanding it with fine sandpaper, but that also did not work (and I fear it may have made matters worse). Does anyone have any suggestions as to what I should do?

Thanks!

I know nothing about this changer--but can give you a couple of general pointers--
First--increasing/decreasing the size of an idler wheel will make no difference in most cases.
2nd, Spring tension will make a difference in most cases. If the spring is "shortened", it will, many times force the idler wheel onto the motor post with enough pressure to ruin the top motor bearing-as it "pinches" the wheel between the two contact points.
3rd, If the motor, idler wheel and / or the turntable is running on "oilite" (brass) bearings, I suggest that ONLY a 20 wt. ND oil be used. Any "old" oil must be removed, as it can become gummy" and cause a slow speed situation. I have seen various oils called "turbine oil"--
Hope that helps, and that someone who knows that TT chimes in--- Ron Rich

Thanks so much for you quick reply. I will definitely look into the spring.

Just for clarification, the "turbine oil" I have used is non-detergent and in viscosity is comparable to 10 wt SAE crankcase oil, or about 25 ISO viscosity grade. As such, it is a very light oil. Also, I did not try to reduce the size of the idler wheel itself, but rather the shaft on which it turns (in an attempt to reduce binding). I am concerned, though, that I may have roughed it up in the process, actually increasing friction.

SANDING the idler shaft?????????
You've now added rumble to the mix, and might as well toss that changer to the trash.
Stop messing with it like a backyard mechanic and leave professional repairing to the professionals.
-End.

Thanks for your reply, MattTech.

To clarify further, I did not go to the idler shaft with 60 grit aluminum oxide or anything like that. I gave it a light sanding with 1600 grit silicone carbide (which has about the abbrasiveness of bond paper), and my intent was simply to remove any vestiges of built-up lube or oil and any surface imperfections on the shaft. The changer continues to operate with no rumble and is steady at the correct speed once it gets going (checked with a strobe disk). Except for the slowness in getting started and after dropping a record, a hesitancy to get going after dropping the first record (generally requiring me to manually turn the platter a quarter turn as it meets the resistance of the cam), and the platter misalignment I mentioned in my first post, there are no other problems other than what I described.

Anyone have any helpful advice? Or MattTech, given that you are up the road from me in Philadelphia, and are a "professional," got some time for this "backyard mechanic" to come up your way to have you check it out? If it would be helpful, I can post a video on YouTube showing exactly what is going on with the changer.

I just made and posted to YouTube a video to demonstrate what is going on. Also, the idler wheel seems to be catching a bit better now (little-to-no slow-down on change, no need to manually turn the platter on start-up), but the start-up is still a bit slow. Also, you will see the wobbling on of the platter, and hear some ringing that I believe is the idler wheel linkage rubbing against the rim of the wobbling turntable.

http://www.youtube.com/watch?v=M0L79W3JSZE

Forget the "wobble" of the platter... mass produced platters are not perfectly stamped out.
Is the inside of the platter rim where the idler touches it clean?.... windex.

A careful slight sanding of the idler edge with fine grit emory paper helps to remove and glazing/shine.
Keep it flat and level when de-glazing like this> [---||---]
avoid "rounding" the edge. like this> (---||---)
It should be soft, pliable, and have NO shine when held up to a lamp.
Reinstall it on the shaft with the washers and c clip and a drop of oil, no more.

The three rubber grommets mounting the motor assmbly should be in good shape, not hard or flattened down.
They should look like rubber cones not squashed down from the motor weight.
A drop of oil on the top/bottom motor bearings helps.

The idler arm pivots and associated speed-change linkages all tend to bind when the old grease/lube dries up.
Dissassembly and cleaning/re-lubing are needed.

Get some solvent or spray de-greaser.

The pot metal cycle gear should be removed..... it gets stuck to its shaft, the shaft then spins with the gear and causes poor/sluggish change cycle performance... remove/clean the gear and the groove underneath it.... relube with light grease. Also oil the little rotating pin that rides in the groove.. it should turn freely by hand.
The trip mech on the cycle gear should be cleaned and left dry... those small parts should move extremely free... no oil on them.

I'm booked up at my shop till December with restorations and running out of room to take in more.

After watching your video, some things come to mind. 1. As Matt said don't worry about the platter and your horizontal movement is caused by the record stamping which is very common due to poor production controls. 2. You should not be using an eliptical stylus on a changer as these stili are designed to operate on one plane only. Use only conical styli on changers. 3. Your idler does appear to be the culprit. It should spin much more freely than that. You can try crocus coth on the shaft to polish it though if the clearances are messed up it will not be able to ride properly on the oil film and will do just what it is doing. Re-clean the shaft and wheel, polish it, lube it and try again. Your alternative is replacement with a good used assembly. The wow you are hearing is from the off center stamping of the record. Hope this helps.