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

[gkimeng]

The slight oil pocket between the thrust bearing plate and original delrin plate removes a good portion of spindle nosie due to changing wave reflection into a dispersive media. Kinda like an "acoustic" platform for the spindle. Also it gives a single tangent point of rotation vs the "ball and socket" that was formed by wear of the spindle ball end into the delrin plate.

Marc, your thrust plate came up over on AK in a discussion about replacement parts. Would this work as a replacement, or does it need the original plastic disc under it to function properly?

[rw_design]

rw, if you need a hand please let me know, I'm also in NY...

Thank You! I am taking my time with it but to be truthful I wish it were finished as I would like to hear the table. Sometimes it's best to leave things alone and see where it takes you. I am thinking I will polish up the bearings, disable damping, mount the platter, new belt and Grado Black1 and give her a try.
The damping mechanism really confused me and still does. Mounting the arm to the spindle with out damping (pin pulled) is confusing but I will figure it out. From what I can tell I am left with the two pivot points and the spindle bearing to worry about. I would like to track at about 1-1/2 grams.

Thank you for offering to help. Nice of you.

[gkimeng]

The thrust plate is only .010" thick so it wont replace the delrin plate, also as I stated the oil cavity plays a role in its function. If the delrin plate is missing, a hard plastic "O" ring of similar thickness can be used. Again, a key point in its function is the "pond" of oil directly below the tangent point of the spindle to thrust plate.

PS: how do I find that thread?

http://www.audiokarma.org/forums/showth ... 793&page=2

[solex]

The damping mechanism really confused me and still does. Mounting the arm to the spindle with out damping (pin pulled) is confusing but I will figure it out. From what I can tell I am left with the two pivot points and the spindle bearing to worry about. I would like to track at about 1-1/2 grams.

Thank you for offering to help. Nice of you.

After you remove the pin, the key is to fix the brass barrel in pot metal housing using some Teflon tape wrapped around the brass barrel (Marc's "" suggestion) the arm should pivot only on the needle screws and delrin bearings. Once I did this it corrected all tracking problems...

[rw_design]

So I pull the pin then wrap the brass barrel with teflon tape until it fits snug innside the housing like a press fit? Where is the flat spot oriented?

My next question is do I turn the spindle post tight against the flat spot of that inner brass barrel and leave it there? I have a teflon washer and the felt pad style no spring in it.
I do not know how to assemble the spindle post into the barrel assembly with the pin removed and now wrapped in teflon tape.

Once I get that far I can pretty much put the arm together and test the table. The arm will be free to pivot up and down and I can set the VTF and test the table wouldn't you think? Of coures I have to lube the spindle well and bearing with oil.

Stuck here...Thank you Solex. This is helping me but as I wrote I am stuck right here.

[solex]

So I pull the pin then wrap the brass barrel with teflon tape until it fits snug innside the housing like a press fit? Where is the flat spot oriented?

Yes it should fit snuggly and the flat spot should be at the bottom so it is aligned with the threaded part of the spindle.

My next question is do I turn the spindle post tight against the flat spot of that inner brass barrel and leave it there? I have a teflon washer and the felt pad style no spring in it.

Yes this is correct, you can also leave the washer and pad in place

I do not know how to assemble the spindle post into the barrel assembly with the pin removed and now wrapped in teflon tape.

Did you remove the arm? If it is removed it should be relatively straight forward. Put the arm back on and adjust the pivot bearings (the spindle must be in place on the t-bar before you put the arm back on).

Once I get that far I can pretty much put the arm together and test the table. The arm will be free to pivot up and down and I can set the VTF and test the table wouldn't you think? Of coures I have to lube the spindle well and bearing with oil..

VTA is set with different size ball bearings and there is not much adjustment here, the spindle and barrel assembly should not move as one...

[rw_design]

[/quote] the spindle and barrel assembly should not move as one... [/quote]

So you mean the spindle and barrel should be a fixed assembly with no movement at all. Like a rigid "T". Tight??
Yes the arm is removed and all these parts are disassembled carefully for cleaning . I have not pulled the pin yet.
Thank You!!

[solex]

Sorry I meant that they should move as one, yes like a T

[gkimeng]

The "AR original" method of adjusting VTA is by inserting spacers between the cartridge body and headshell, either in front of or behind the mounting screws. Tinkering with the spindle threads or balls can provide some fine adjustment, but if your cartridge is grossly different from average, nothing will take the place of a 1/8" thick block of plastic in the right place.

[rw_design]

Sorry I meant that they should move as one, yes like a T

The assembly should have no movement then. The drum cannot move at all and the spindle is tight. Almost like a hammer one solid piece.

[solex]

The assembly should have no movement then. The drum cannot move at all and the spindle is tight. Almost like a hammer one solid piece.

Sounds like you got it...

[ddarch]

bump

[MuZak]

Threads that go bump in the night...

[MuZak]

Just sent you a PM on the topic...
Been listening to the Merrill mod table when I can listen
at all lately.
Still blows me away.
Needs a few finer points addressed down the line though.
Next on deck is the restore of my original XA, using
your top plate and inner platter!

How "bout yourself?