AR bearing

[Gordon Steadman]

Does anyone know how the bearing on this old AR deck works?? Normally I expect to see a ball bearing in the bottom whith a flat or slightly curved surface on the bottom of the shaft. This one has a cup (5mm) and the doesn't appear to be anything at the bottom of the bearing. i would expect a ball bearing to just sit in the cup and drag, certainly the platter doesn't revolve for very long. I tried dropping in a small ball but the platter still drags.

With all the arms I'm making, I though it would be a fun project to get this one working again somehow. All I have is the platter, sub platter and bearing. I was thinking of rigging up a rim drive of some kind, although a belt would obviously be easier. I have an old Dual motor somewhere I could use or maybe the one out of the SP25.

[karma67]

That's the same set up as on my AR turntable too.

[Gordon Steadman]

That's the same set up as on my AR turntable too.

Hi Jamie,

Does that mean there IS a ball bearing in there?? Can you tell me what size it is?

[karma67]

No there isn't mate. The platter end is dished out to mate with the spindle but will check to be sure tonight for you

[Gordon Steadman]

No there isn't mate. The platter end is dished out to mate with the spindle but will check to be sure tonight for you

I've just used a feeler down the bearing shaft and there is definitely a dip in the bottom!! The ball I put down is obviously too small and allows the two flat surfaces to touch.

[karma67]

now youve got me wondering if mine is missing!

[Gordon Steadman]

now youve got me wondering if mine is missing!

The bearing has a step about 25mm down and then goes a further 12mm to a cup at the bottom. There is obviously an insert missing. I cut 11mm off a 9mm metal drill and drilled a small cup into the end. Dropped that in, then a ball bearing and put the inner platter in. It now revolves very freely indeed. With the main platter on it goes for ages.

Rigged it up quickly with an old Dual motor and belt. Had to fiddle about getting the pulley the right size, in the end I used a modified slot racing wheel. It's running at 34 rpm at the mo but I'll adjust that later. Tried it with one of my new arms and it sounds quite decent. I think I'll fix it to a lump of worktop I have and it can be used as a testbed. I suspect that to actually have six TTs to use might be considered slightly over the top, especially as I claim not to be a collector - me and my system in every room.

[karma67]

i think ive got confused by your first pic,mine has,on the end of the spindle a machined end,sort of like half a bearing,a nipple for want of a better word,which then sits on what looks like some sort of white plastic down in the bottom of the well.your platter at first glance looks the same but im guessing it actually got a dished out end to take a ball bearing?
changing the topic slightly ive bought some ebony from timberline (have you heard of them?) so should be busy soon making a tonearm board.
regards.
j.

[Gordon Steadman]

i think ive got confused by your first pic,mine has,on the end of the spindle a machined end,sort of like half a bearing,a nipple for want of a better word,which then sits on what looks like some sort of white plastic down in the bottom of the well.your platter at first glance looks the same but im guessing it actually got a dished out end to take a ball bearing?
changing the topic slightly ive bought some ebony from timberline (have you heard of them?) so should be busy soon making a tonearm board.
regards.
j.

Ah, obviously a different model then, I think mine was an EB101 or something like that. haven't heard of timberline, I used to get all my guitar supplies from Touchstone in Reigate.

[karma67]

ah is see.they are based in tonbridge,been there yrs,i used to get my timber from them back when i was an antique restorer/cabinet maker. :)

[Gordon Steadman]

Got the old AR working quite well.

This is going to be a test bed basically. Two arms so far with two to come!! One shorter one and a parallel tracker.

Actually doesn't sound too bad but pretty it ain't!

[The Barbarian]

Does that mean there IS a ball bearing in there?? Can you tell me what size it is?

Gordon there should be a ball end on that Sub platter spindle. Seen as you drilled the bottom :rolleyes: drop a new thrust plate in the bottom of the housing.

To keep the bearing on the end of the spindle to stop it falling off while you insert it back into the housing, put a dab of vaseline on the end :eyebrows: press the new ball bearing in place. Dont over fill the housing about 8 drop of oil will do.

Is the foam washer around the bearing housing rim still intact?

[karma67]

i still not 100% sure if i should have one on my AR the turntable???

this is what i have,

http://i1267.photobucket.com/albums/jj548/jamiecreig123/20150306_172758_zpsugxwqidl.jpg

and in the well i have a white disc with a small dished out part to receive the ball end of the spindle.

http://i1267.photobucket.com/albums/jj548/jamiecreig123/20150306_172837_zpsymmnzpkt.jpg

as it is,the platter spins freely with no noise.

[Gordon Steadman]

Gordon there should be a ball end on that Sub platter spindle. Seen as you drilled the bottom :rolleyes: drop in a new thrust plate in the bottom of the housing.

To keep the bearing on the end of the spindle to stop it falling off while you insert it back into the housing, put a dab of vaseline on the end :eyebrows: press the new ball bearing in place. Dont over fill the housing about 8 drop of oil will do.

Is the foam washer around the bearing housing rim still intact?

In fact Andre, when I took it apart today, there was nothing in the bottom at all, the bearing was open all the way through!!! So I fitted a washer to the bottom and dropped the ball in. The platter now just clears the top of the bearing block and spins awy with no problem. Don't remember how the bearing got like that,. Probably the result of one of my 'experiments' in the dim and distant past.

Certainly a different design to Jamie's.

[The Barbarian]

The white disc in the bottom of Jamie's Bearing housing is a Derlin Thrust plate. That is fitted to cut down noise, i would fit one into yours if i were you Gordon.. You certainly don't want a washer.

[Gordon Steadman]

The white disc in the bottom of Jamie's Bearing housing is a Derlin Thrust plate. That is fitted to cut down noise, i would fit one into yours if i were you Gordon.. You certainly don't want a washer.

Thanks Andre. I think if this was going to be used as a serious music machine rather than just a test bed, I would certainly do that. For now, it just has to go round for a short while and tell me how well the arms work. If something seems good enough to play with further, I can transfer it to the OL and see just how good it is. I don't want to disturb the good deck unless I'm pretty sure it is worth it.