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The Suspense is Killing Me


thebes

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Well now it's official Thebes my man. Choose your instrument of punishment: pine or your choice of any american hardwood (no ebony imports). Hickory is of course traditional, but please consider pecan, oak, maple, mesquite (for that southwestern flair, so hard it destroys saw blades)? I might consider bamboo, if it is split into shreds at the whipping end....

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Now that's a thread title.

Pine for an armboard...nobody uses soft woods for amrboards. Stiff and hard just like the twins like it. I don't really know why but it is true. People seem to like Ebony #1. I will trust the everybodies in this case and steer clear of soft wood arm boards.

Does the Ariston have a two piece platter? In other words, an inner platter that has the spindle and an outer platter that sits on the inner. If so, are you sure you have the outer platter properly placed on the inner platter? There's no goo, funk, metal burrs where the two platters meet?

I wait for you answer before going further.

Thanks Scott. Nice to have an expert on the job. Ok ,so armboard materials do make a difference in over all sound so that can be addressed down the road. I can probably con my brother into running up a new board for me.

As far as the Ariston, think Linn. Early Linn's and Ariston's are the same in everything but the shape of the armboard and location of the on/off switch. It's a two piece platter, appears visually to be in round (no way to tell for sure without bringing it to a machinist) and no burrs etc., The outer plate fits snugly and the motor adjustment is perfect with the belt running straight and true and very, very close, to proper speed as tested with a strobe disk. The 3 springs are centered on their rubber mounts, which are not dried out. Motor is new and the platter wobbles with or without belt attached and with or without outer platter attached.

The details on the the spindle are outlined in my just previous post.

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Right. I'm pretty familiar with the Ariston, just wasn't sure about the platter. If it is the suspension causing the wobble, then the armboard(and tonearm) will also be wobbling along with the platter since they are all part of the same sub frame. Does the armboard seem to move or sway along with the platter? If not then it's got to be a bent spindle on the inner platter. You don't need a machinist, any right angle square held against the spindle and the inner platter should give you an idea if the spindle is bent. You did say you dropped this table? Or was that a joke?

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A $180 joke because that's what it will take me to replace the broken stylus. I was fitting it between two levelled speakers so I could reach underneath and adjust the springs when it took the plunge.

It was wobbling before that so I don't think dropping it had anything to do with it. Really good idea though. I can't find my t square but I tried a couple of other things and if it's bent it's only a smidgen. Looking from the top down it looks a little bent but that could be my eyes playing tricks. The armboard and arm don't move at all when it's spinning. I do have it adjusted with the least amount of wobble I can get out of it, and armboard is set at right height in relation to case.

I'll see if I can find my t-square tomorrow and find a good level spot with good light, drill out a hole in a nice flat piece of wood and take a better measurement.

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"Motor is new and the platter wobbles with or without belt attached and with or without outer platter attached."

I am no expert on suspended designs but if the sub-platter is wobbling then it sure sounds like either the bearing or the centre spindle is the issue.

If it is the centre spindle then one would expect the wobble to be consistent - in other words the same part of the platter dips or rises all the time. If it is the bearing then the wobble is probably not consistent I'd guess.

If you have consistent wobble then I would surmise that inserting something between sub-platter - like a tiny wedge - could level the main platter for you and mask the effects for playback.

Just as a thought - are there any alignment marks for the platter / subplatter? My table has them for perfect alignment. Might be a factory supplied wobble....

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Max mentioned the bearing well. Good to check that too. Make sure it doesn't look damaged, loose, banged around. Sounds like you might have a bent spindle. Even bent a little would be quite a wobble. Max also mention, if it is the spindle, it would tend to do it's swoop in the same place. If you could find a square(actually a ruler will do), you could put the square on the platen, next to the platter and spin the platter slowly by hand and measure it's height at various locations around the platter. Mark the low spots with a piece of tape or something.

By the way, simple test to see if the suspension is close to being correct is to push straight down on the platter and release. Things should bounce generally up and down only for a second maybe two seconds at most. Shouldn't see much side to side bouncing.

One more thing, if you're prone to dropping your turntable, always remove the stylus when working on it.

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Good call guys. Drilled out a hole in a piece of wood for the top spindle, placed it on a table and laid a square completely across the the lip of the inner plate. At one spot the spindle is indeed off by just a smidge (1/64"?).

Put it back on the table and the inner plate rises about 1/16" on the highest part and about 1/8" on the highest part with the outer platter in place. Taped the high spot and checked it a few more times with same result.

By the way I can give it a spin with my hand (belt off) and it will turn for about 1 and 1/2 minutes before it stops turning. No sound of grinding, clicking and with my hand on the spindle shaft and the motor running I can feel no vibrations from the spindle.

I guess that leaves two choices. Bent spindle or worn spindle shaft

So how do I true up the spindle without wrecking it?

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When you say "off by 1/64", do you mean spindle not perpendicular to the platter? That's what I'm envisioning. At this point, a picture of the underside of the inner platter showing the spindle would be helpful.

You've got it. With the glare from the lights I doubt if you can see much but there is a small gap on the top on the right between the blue tape and the spindle. If I move the blue tape to the other side when the top is aligned even with the spindle the blue tape sticks out at the bottom. Meaning to me that if the platter edge is flat than there is a left lean in the picture of the spindle itself.

The gap is to narrow and there is too much reflection off the spindle and lights to be able to show much more.

post-14801-1381936010926_thumb.jpg

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Make sure you have a ball bearing in the bearing well, if there is a ball bearing maybe the seller just chucked a ball in there to sell the table. You can buy different size balls at ACE Hardware, just a thought! Also make sure you have the correct weight oil in the bearing, a heavier viscosity will reduce the amount of play in the bearing.

Phill

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Make sure you have a ball bearing in the bearing well, if there is a ball bearing maybe the seller just chucked a ball in there to sell the table. You can buy different size balls at ACE Hardware, just a thought! Also make sure you have the correct weight oil in the bearing, a heavier viscosity will reduce the amount of play in the bearing.

Phill

Phil you might have something there. From the looks of that spindle.... it does look like it is supposed to be riding on a ball bearing. It looks flat on top.

Martin, how about a picture of the tip of the spindle, looking down on it.

Linn spindles do not have this. They are machined to a cone shape at the tip.

Edit... parts list as seen in the manual on page 8, lists a Ball Bearing Main Shaft. Better make sure you have a ball either captively held on the tip of the spindle or sitting in the bottom of the bearing well.

http://www.vinylengine.com/library/ariston/rd-11s.shtml

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Yes this does ride on a bearing. I dropped it out and it appears to be completly smooth and seems to be the right size. Looked at the bearing seat and that looks to be smooth.

I'm using light machine oil right now. I think I may have some 50 weight motor oil around here someplace and I can try some of that.

Hopefully the picture shows the light scoring on the shaft.

As an experiment I put two heavy 1/2 sockets from my wrench set on the top edge of the platter located directly on the high spot and that smoothed out the wobble almost completly. With one socket it still wobbles. With this setup the armoboard does dip on its suspension when the weighted side of the platter gets near it.

We're talking maybe a pound of weight here since these are 1 1/4" cast steel sockets. Even using auto tire weights I doubt if I could mount enough and still have the inside of the platter clear the motor wheel.

What next my good friends?

post-14801-13819360151192_thumb.jpg

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Platter was removed, an eraser head was over the spindle cavity to keep the bearing from falling out and it was shipped in it's original packing box with proper foam packing materials.

It's been knocked arond a bit over tyears. Various scratches and gouges on the top of the platter and you can tell it was set too low at least once because there is scoring where the top of the motor wheel scraped along the inside of the outside platter.

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As an experiment I put two heavy 1/2 sockets from my wrench set on the top edge of the platter located directly on the high spot and that smoothed out the wobble almost completly. With one socket it still wobbles. With this setup the armoboard does dip on its suspension when the weighted side of the platter gets near it.

If weights keep the platter spinning level and the armboard is dipping everytime the weights role by, this would confirm to me that the spindle is not perpendicular.

I would try to get the spindle straight. How about you install the inner platter, then try to push down on the high side while lifting up on the low side. Twisting, so to speak, the platter back to level. That would be the amatuer method (me). Or, if you know a good machinist, you could try to have him straighten it. Not that there's any machining involved but they might have the measuring tools needed to be sure they force the spindle perfectly 90 degrees.

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Thanks once again Scott. There does happen to be a fellow forum member near me whose a machinist among other things. I should be able to hook up with him soon and let him have a go with it.

Actually quite interesting deductive skills you employed in bringing this to a conclusion. I've also enjoyed the challenge of figuring this out. It's a good cautionary tale on what to look for if you actually have your hands on a turntable before you buy it. (this came off Audiogon so not applicable in this instance).

Any word on the Elac? Still be happy to help out.

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