A new turntable project is about to start.

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Wayner

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A new turntable project is about to start.
« on: 24 Jun 2010, 09:08 pm »
I recently scored a nice AR ES-1 tonearm and the floodgates have opened for a new table project.

 

The platter and bearing will be from the AR-XA turntable, motor is the Hurst 3001-001, 300 RPM synchronous (12 pole) and the the body may be 5/4 composite deck plate. The motor assembly will be like the one in ARMod, separate from the table body and linked only by the belt.

The decking material is made from recycled material and I believe it to be sonically inert as well as expansion/contraction stable, so a good candidate to couple the platter and tonearm together. I also know that the decking material is extruded and has hollow sections within it, perfect for stuffing lots of platiclay into. My friend is going to precision water-jet the mountings for the platter and arm base and will hold tight tolerances.

That's the new plan, anyway.

Wayner  :D

Listens2tubes

Re: A new turntable project is about to start.
« Reply #1 on: 25 Jun 2010, 01:37 am »
COOL looking arm! So why can't I find any info on it?  Seems the ES-1 is a turntable that never has this arm on it. :scratch:

Minn Mark

Re: A new turntable project is about to start.
« Reply #2 on: 29 Jun 2010, 07:46 pm »
keep us posted !!

 :green:

Mark

Wayner

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Re: A new turntable project is about to start.
« Reply #3 on: 29 Jun 2010, 09:04 pm »
Motor starting capacitor finally arrived. This motor is made by Hurst (a division of Emerson) and is a very torque loaded. It is also an excited motor, that would not work suspended, because of it's internal energy (mechanical) and must be designed in a housing that will drain off the mechanical energy. Running the motor as shown, one can feel the pole locking vibrations, but with pressure to the two mounting tabs, can render the vibration to almost zero.

 

This means the table design will have to have a SAMM (stand alone motor module), to keep the motor completely isolated from the plinth. I am also going to have to consider a mounting method that will put the motor under pressure, against some mass, to drain the mechanical energy. The centers of the mounting holes will also have to be inline with the table spindle, to prevent the motor from hinging on the 2@180 degree mounting holes. This is kind of a bad design, and I wish the motor had 4 mounting holes in a bolt square. If I want to use this motor, I will have to over come this problem.

Wayner

Minn Mark

Re: A new turntable project is about to start.
« Reply #4 on: 30 Jun 2010, 12:35 pm »
Could one 'suspend' the motor in a cavitiy in the plinth using compliant cords (aka mini 'bungee'  cords) to decouple the motor and sink the mechanical energy a la the Pro-ject Debut??

Could one house the motor in the plinth inside a 'can' filled with plasticlay?  The outer appearance could then look like the VPI classic, but the hole in the plinth could be enlarged so as to not touch the 'can' housing the motor? Lots of options to optimize the aesthetics.......

Looks like a great project, Wayner.

Mark


Wayner

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Re: A new turntable project is about to start.
« Reply #5 on: 30 Jun 2010, 04:30 pm »
Mark,

Almost all of this design is driven by the tools that I own. That would be a nice drill press and a power miter saw. Cut and drill, that's about it. There is that old saying from design skool, that "things look like how you made them". Again, from my many years in manufacturing, I have learned that it is not what you make, but how you make it. When I get to drilling the holes for the tone arm and platter bushing, I'm going to see my buddy who will put those holes in at a tolerance of +/-.0005. The rest will be done by myself as they are no where near critical at all.

My design (in my head) can go 2 possible directions. In the first design, it will look and function like ARMod, using different plinth and SAMM materials. It will be easier to make, but I may need my buddy to make me some end caps to cover the 5/4 decking material (to make it perdy).

The other design came about after a couple of beers the other night. I'm using an AR-XA platter, sub platter and bushing for the turntable. If I eliminate the outer ring and put a 1/4" thick piece of poly on top of the sub-platter, I can put the motor and pulley assembly much farther away, using a longer drive belt. I can't cut any material until the arm arrives, so I'm slightly on hold.

Wayner

BobM

Re: A new turntable project is about to start.
« Reply #6 on: 30 Jun 2010, 04:54 pm »
Wayne - do you have any kitchen contractors around your area? Do any of them make Corian countertops? You may be able to pick up a sink cutout and make a Corian plinth out of it; a very inert and dead material.

Be careful cutting and drilling it though. It kicks up a lot of dust.

Bob

Minn Mark

Re: A new turntable project is about to start.
« Reply #7 on: 30 Jun 2010, 05:58 pm »
Wayner,

Ahhhh...I like the 'coupla beers' design idea...for as the apostle St. Paul said (of wine),

"No great poetry was ever written by a drinker of water."

Please post pictures, details,etc of the build. I know I will learn a lot about the innards and workings of TTs this way.  :thumb: Thanks.

Mark

Wayner

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Re: A new turntable project is about to start.
« Reply #8 on: 3 Jul 2010, 01:09 pm »
The AR arm came yesterday. It's a really nice arm. The body pieces are carbon fiber, counterweight seems to be brass, with possible carbon fiber arm tube, and headshell. Everything is adjustable, including VTA and Azimuth.

 

 

Wayner

Listens2tubes

Re: A new turntable project is about to start.
« Reply #9 on: 3 Jul 2010, 01:30 pm »
Man Wayne you can sure find stuff that gets us going! :eyebrows: What vintage is this beauty?

Wayner

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Re: A new turntable project is about to start.
« Reply #10 on: 3 Jul 2010, 03:07 pm »
I think the arm is from the early 80s, but not sure. Not lots of info on it, but I haven't yet checked the vinylengine. Today, the mission is to get the new Sony PS-X7 going.

Tomorrow, I will officially start this project. I will be looking for input on a few ideas, so some if want, can put on the thinking caps.

Wayner  :D

Wayner

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Re: A new turntable project is about to start.
« Reply #11 on: 4 Jul 2010, 09:17 pm »
Now I'm doing some fun math for calculating the best possible distance for spindle to pivot distance for the AR ES-1 tonearm. If I recall, the AR turntable and the ES-1 were kind of the same deck from the 80s. I know that most of these decks were fitted with a version of the AudioQuest PT series, like a  5 or 6. That P to S distance is 211mm as published by AQ. Using my Lofgren B calculator, that puts the overhang at 18.601mm, producing a 229.601 effective length from pivot to stylus. If I subtract the 10mm stylus to mounting hole spacing, that puts the mounting screws at about 219.6mm, or about 8.64 inches to at least the inside mounting screw (on the PT-6) and that also seems to put the mounting screw position on the AR arm at least in the slot area, so this should work.

W

Wayner

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Re: A new turntable project is about to start.
« Reply #12 on: 5 Jul 2010, 06:53 pm »
I think we have a good start on the design for the plinth.

 

The material (composite decking) is very stable, and non-resonant. Tomorrow, I will start making parts, if I feel good about the design, tomorrow. The body is a double layer, encapsulating the bearing and tonearm collar. Haven't quite figured out how to exit out the RCA female jacks yet, but the logical place is out the back, or left side.

Wayner

Wayner

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Re: A new turntable project is about to start.
« Reply #13 on: 6 Jul 2010, 07:17 pm »
I am close to getting the plinth done. I'm going to quite for the day while things are going good.

 

Wayner

rcag_ils

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Re: A new turntable project is about to start.
« Reply #14 on: 7 Jul 2010, 03:04 pm »
Quote
That P to S distance is 211mm as published by AQ

shouldn't this is where the hole should be from the center of the spindle?

Wayner

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Re: A new turntable project is about to start.
« Reply #15 on: 7 Jul 2010, 08:01 pm »
Yes, centerline of spindle to centerline of tonearm pivot.

I have the main structure finally assembled today. Had to redrill an inner hole, no big deal. I also had to shorten the length of the body, behind the tonearm, as the leads from the tone arm were not long enough, and I didn't want to splice them. My only goal tomorrow is to get the RCA jack plate installed, and wired. Then this portion will be done and on to the SAMM.

 

 

Wayner

rcag_ils

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Re: A new turntable project is about to start.
« Reply #16 on: 8 Jul 2010, 02:22 am »
Then the hole for the arm should be 211mm from the spindle, not 219.6mm.

Wayner

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Re: A new turntable project is about to start.
« Reply #17 on: 8 Jul 2010, 11:50 am »
P to S stands for Pivot to Spindle, not pivot to stylus. 211 from pivot to spindle it is.

Wayner

rcag_ils

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Re: A new turntable project is about to start.
« Reply #18 on: 8 Jul 2010, 03:47 pm »
That's want I meant, that's where the hole for the tonearm should be drilled. Then the 219.6mm has no bearing for the installation, it just confuses the issue, because once the hole is drilled, there's nothing you can do about the pivot to stylus, you just have to live with what you have, pivot to spindle is the key to tonearm installation.

Wayner

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Re: A new turntable project is about to start.
« Reply #19 on: 8 Jul 2010, 05:46 pm »
OK, I didn't mean to confuse anyone. Oh, I get what may be confusing. The 219.6mm is the distance from the tonearm pivot to the screw holes on my cartridge. I had to know this number to make sure the cartridge had enough "slop" in the slots to achive the points I wanted. 219.6 has no other reference to anything, and is just a number I used to do a check on null point geometry.

Wayner