Pulley for AR-XA (and how to polish your spindle)

[OldRelayer]

I searched the forum, but didn't find a satisfactory answer to my question. But that may be more the forum search, I do a lot of these forums and not one of the search routines work.

I bought a project table. Once it is nice, I will use it for a while, as I work on mine a bit more and hope to learn more as I go along and then sell it.

Two things about the pulley. It wobbles, more than the two tables I have had in the past, but they all do to an extent and it is well known that it is a real weak spot of the table. The other thing, is that it comes off the motor way to easy, I am use to a struggle to get it off.

I know that Dave sells really nice ones, but I would never redeem my money from a table I bought to sell. I know that some people use Silicone caulk to stabilize the pulley and add a little mass. I actually tried some plumbers putty just to see if it would have any affect, it didn't.

Any ideas are welcome, either on how to fix this one up or where to get a better one that won't be cost prohibitive.

Thanks,
Barry

[pivot]

Are you sure the pully itself is the source of the wobble and the motor shaft is not bent?

Remove the pulley and watch the motor spin to make sure. If it is the motor shaft you may be able to straighten it by protecting it with thin leather and CAREFULLY and SLOWLY bending it with pliers You may not get perfect but I have been able to get "pretty good".

Sometimes only the edge flange of the pully is bent up a bit and it only looks like the whole pully is wobbling. Check that.

[OldRelayer]

Thanks Marc, Thanks Pivot for you thoughtful posts.

Pivot, the motor is pretty good I think it is strong and quiet, shows no sign of being out of round either when running or not until you put the pulley on. I am not totally sure what is wobbling, my personal table has a bit of the same thing going on but to a much smaller degree and in the process of figuring this out, I will probably have a better table. Part of what this is all about for me is learning more so I can not only make a nice table for resale but also make mine better without spending a fortune(which I don't really have). I will try to see if it is bent in some way. Do you think it is strange that it comes off so easily, when I first did this AR (when they were still in business) said stand on the table if you need to, to get it off, it was on there pretty good. The pulley is feather light and I can see how more mass could help, ergo people filling with whatever. I have heard such good things about Dave's pulley, but geezeee it is expensive. I don't think I would even spend that on my table never mind one that will get shipped off. The table for all its cosmetic problems is actually pretty good audio wise and matches up with the Stanton 680 I put on it very nicely, I guess a whole other subject, I sure like the 600 series Stanton on the AR-XA, really brings it to life without a hint of harshness.


Marc, I agree.... where to start. You always impress me with your knowledge and your willingness to share it with us neophytes. It seems that much of the contact issue can not be resolved no matter how much better the pulley may be, other than getting a tad more out of it by not having high spots. Personally In don't care if my table has the capability to play 45's but it might limit the market for it, but maybe not, most people don't have the patience for just a 20 minute album side never mind a 5 minute track that you have to jump up to take off because there is no auto return. I will have to read your post a few more times to see what I can glean from it.

Are there other options for pulleys? Who may manufacturer them and who may sell them? The cost of Dave's pulley is twice what I paid for the table, I did get a good buy but I have a hard time believing anyone will think that was a good investment and pay additional for the table.

Thanks guys,
Barry

[OldRelayer]

Marc, I didn't know you sold pulleys or did I misunderstand. If so do you have a write up and a price list? As stated I don't want to get to crazy with buying things for this table if I can get it back when sold. Actually I wasn't going to do anything to the pulley until I was absolutely sure of what I was doing, even a $.20 part like this pulley in 1970 or so would probably be impossible to find. Thanks for the heads up on the pulley speed gauge.

I just had a look and don't know how to find the speed gauge, where exactly is it?

Thanks,
Barry

[pivot]

The only replacement pulleys I know of are the two co-polymer Merrill/Scilla units (just 33 1/3 and one 33 1/3 and 45) from Vinyl Nirvana and the double belt unit from Sound of the Wood.

I have not heard the SOTW double belt unit so can't comment on that. ( - is the SOTW pulley system the double belt unit you mention using?)

My experiance:
I was experiancing some noise breakthrough on my AR which I ended up attributing to the motor/belt/pulley. I tried modding the stock pulley by adding some silicone caulk to both the top and bottom cavities. I noticed an improvement/reduction in noise and I decided to give the co-polymer pulley a try.

The replacement pulley from Vinyl Nivana is impressively well machined. Not only does it not wobble it is hard for me to tell it is moving at all.

To my ears, on my gear, it is a major upgrade, well worth the cost.

If you purchased the upgrade pulley for your own table you would then have a "spare" stock pulley to experiment on. Loading the cavities with clay, silicone and/or lead is a worthwhile experiment.

I am very interested in hearing more from on his own investigations.

[OldRelayer]

oK, Marc now I understand. I would understand that to mean your pulley modification would be an improvement or why would you bother. Yes, I will send you my snail mail in a PM. The polishing is something that I have been trying to learn more about, not just the part that is taken out but also the shaft and the part that is hard to get at and to see. It feels like the bearing is in the tonearm shaft which is well lubricated but I can't see it, but I haven't actually shinned a light right in but my lighting is pretty bright and I think I can see down but it might not be far enough. So any information on cleaning and polishing would be graciously accepted.

What is your thought on deadening for the table, I have seen that done on the inner platter that does ring like a bell when not part of the larger platter and seems simple to do and not very expensive? I did paint the top with what was suppose to be Wrinkle paint, but it just looks like high gloss black to me, but the sandy finish underneath comes through and it does look reasonable, certainly a lot better than it did.

[ar3a]

Hi Marc,

Could you please provide me (and others in this forum) instructions on how to polish the ball end of the spindle? I've been trying to do this, but was not be able to make it mirror finish like you said.

Cheers,
VA

[ddarch]

Marc,

How about copy/pasting this response into a new thread called "Polishing your drive platter spindle" or something similar? This is great info that will be difficult to search otherwise.

Dave

[OldRelayer]

Good idea Dave. I do have a question, what is 1800 crocus cloth and where do you get it?

[danieldust]

Good idea Dave. I do have a question, what is 1800 crocus cloth and where do you get it?

I thought I was the only one who didn't know.

Yes, please post this in a new thread. I have a question, but I'll save it for the new thread.

[gkimeng]

Good idea Dave. I do have a question, what is 1800 crocus cloth and where do you get it?

Crocus cloth here:

http://tinyurl.com/688563

Currently the finest stuff they're showing is 1600, which is still pretty darned fine.

I polished the ball end of one of my TTs platters years ago using a drill to turn it against a piece of chamois dipped in increasingly finer grades of emery compound and jeweler's rouge. You can find those at

http://tinyurl.com/5spxgq

My other TT uses a 70's XA platter with shaft shortened to TT length. The machinist turned a socket into the end, and the platter rides on a new tungsten carbide ball from smallparts.com.

[OldRelayer]

Thanks guys. I will be going out today so will stop at the auto parts store which is suppose to have such things, according to the guys at the hardware store, I do mean the guys at the HS, not the workers. Marc if I can't find it locally, I will take you up on your kind offer.

How can you change the ball on the platter shaft, isn't it affixed to the shaft? I did discover there was no ball in the tonearm shaft, so I used what I had which was a BB, it is a little smaller and I am sure not as precision as it could be, will need to find the real one, can't be to hard to find, but I suspect you can't buy them by the onezzzzyyy. Does anyone have the real dimension?

Thanks,
Barry

[gkimeng]

How can you change the ball on the platter shaft, isn't it affixed to the shaft? I did discover there was no ball in the tonearm shaft, so I used what I had which was a BB, it is a little smaller and I am sure not as precision as it could be, will need to find the real one, can't be to hard to find, but I suspect you can't buy them by the onezzzzyyy.

Smallparts.com sells BBs individually. I'm thinking of ordering some carbide balls the next time I place an order and experimenting to see if there's any tonearm performance boost to be had from a harder than original ball.

"Changing" the ball in the platter spindle would require machining the old one off and then boring a well into the bottom. I had to do this when I shortened the spindle on an XA platter to fit into an older TT. It's really not worth the effort if you don't have to do something similar; just polish the end.

[OldRelayer]

GK, I didn't see an ball bearing, but they sure have a lot of stuff. A bottle of locktite would be nice to have. The trouble with those places typically is the shipping kills you, if you decide to get some of those BBs and they are not too terrible expensive, maybe we can work something out to make it more cost effective for each.

Marc, it would be a nice to have a couple of sized to be able to have some even if small vertical adjustment on the tone arm. I had to use a couple of washers to screw down a Stanton Cart that has those really thin metal hold downs, it is just enough to throw the vertical adjustment off, not terrible but it would be nice to have it right. Of course my BB isn't helping, it certainly must be smaller than what is called for, haven't had a chance to measure it yet or figure out where to get a replacement. May be GK's source will pan out, I didn't see them, but if he found them, they must be there.

I was able to get some Crocus Cloth today but it is 1200, I assume that it is not fine enough for what we need, I can see the marks on Aluminum, I wouldn't call it a mirror finish.

I did learn something interesting. I was going buy Brasso to use on the weight and the platter, until I read that it should not be used on aluminum. So I bought some metal polish that does a pretty good job on the platter and I found it I hit the brass with #000 Steel Wool and then the metal polish it is pretty much brasso. For those that were in the military, you know all about brasso. In any event both the aluminum and the brass now look great.

Still trying to match up the stain on the leveling frame to the walnut veneer, bought some darker walnut stain today, hopefully will have time tomorrow to try it, the stain takes forever to dry, even on a bright sunny day. I am kind of new to this and probably doing things that I shouldn't. My plan is to offer the table with, A Stanton 680el with lightly used stylus, the leveling frame, a bubble level, a Carbon Fibre Cleaner, an AR tonearm weight gauge, over hang tool and a newly fabricated dust cover. Just seems nice to have everything complete. Dumb idea and I will never get my money back, or a good idea?

Thanks,
Barry