new empire project TT

Berndt · « **on:** 7 Aug 2009, 02:25 am »

The platter is a combination of 2" thick PCV, 2" thick Aluminum plate, and 1" thick Bronze.
It is 45lbs and has a 1" tool steel spindle.
The bearing body is 4" diameter bronze sunk into a 2" thick cast iron plate, the bushing has .001" clearance and has a teflon thrust button.
The arm board is 1.25" phenolic bolted to the cast iron base with a constrained layer of sorbothane between.
The arm mount is 3.5" bronze and will be fitted with a project 10cc evolution.

Total heft is 110lbs as is.

jmpiwonka · « **Reply #1 on:** 7 Aug 2009, 02:41 am »

good god.
badass.

Berndt · « **Reply #2 on:** 7 Aug 2009, 02:42 am »

Wayner, I'll get the 398 remnants off to you either tommorrow or this weekend.
Rim, the SME tonearm cable won't work for me as there is no accomodation for the right angle DIN connector.
Will post more better pics when the arm is mounted and after I determine if I am getting the correct speed.
Cheers, Bill

James Romeyn · « **Reply #3 on:** 7 Aug 2009, 03:20 am »

Empire? What?

My head hurts looking at the pictures, such is the physical impact & form-following-function beauty. The description reads more like Jules Verne sci-fi than something made by a member of an audio forum. When & how did you get time in NASA's machine shop? Speechless doesn't do this justice.

Is the arm overdue?

I surely must see & hear this ASAP. Will bring my custom Ryan Thorell guitar (ETA 1 Sept).

Berndt · « **Reply #4 on:** 7 Aug 2009, 04:09 am »

Jim you started it...(Peter too)
The 10" tonearm wouldn't fit the current empire replinth so I started thinking about the tt I wanted to really build.
I was going to use a galibier platter but the $$$ was too tight.
Sooo, I inventoried my available materials and ended using everything but the kitchen sink in this build.
I also spent some time researching patents to see what kind of ideas were out there for the bearing and platter.
In the end I kept coming back to mass oriented trends. The platter construction uses shrink fits of .015" for the bronze to aluminum interface and the spindle bush is shrunk into the cast iron base to achieve a higher degree of connection between the materials. It just seemed like the right thing to do and the build was actually an organic process that was very satisfying.
I'm really excited to get this deck on the tt stand and drop a needle in the groove to see if it actually sounds good.
I hope the speed is close enough that I don't have to enlarge the pvc driven portion of the platter.
The belt is also driving the platter @ the center of the platter spindle bushing.
The shop this was created in is more blacksmith than Nasa, FWIW.
I am very glad to be a hobbyist, not a manufacturer. I get to make every tt be unique and I don't think I'll make two of any tt design again.

Wayner · « **Reply #5 on:** 7 Aug 2009, 11:31 am »

Bill,

You've slipped into the Abyss! I only worry about the Empire motor's starting torque, but maybe you have that bad boy platter really slippery for start up. You must have started it? Does it get going fairly effortlessly? If It struggles a bit, one trick is to talcum the belt. This is what AR did for their undersized motor. The talc let the belt slip enough to allow the motor to go to full RPM then eventually the platter caught up and everything was happy. I think the speed should be OK once the table is going.

Wayner

James Romeyn · « **Reply #6 on:** 7 Aug 2009, 02:23 pm »

Bill
Suggestion: make one-of-a-kind artisan TT platters (each one unique), at your leasure, put them in display cases. Art work for well-heeled audiophiles. That platter looks like Photo-Shop work.

Berndt · « **Reply #7 on:** 7 Aug 2009, 02:37 pm »

Without assistance the empire pulley wants to just spin out at the belt interface.
My Teres friends taught me the helper spin.
Upon startup I just give the platter a push and the motor can take over.
Still need to ventilate the motor pod a bit more, the pabst motor generates some warmth that you don't notice until you enclose it.
I also need to add a bit more mass to the motor pod to affix its location.

Berndt · « **Reply #8 on:** 7 Aug 2009, 03:00 pm »

Some more pics with an album on.
Also the platter has finally spun all the way down to the teflon button, its final home.
I've positioned the armpod @3 o'clock and the motor pod @ 9 o'clock as this was how I imagined it being when I was building it.

orientalexpress · « **Reply #9 on:** 7 Aug 2009, 03:12 pm »

sweet,i see u tommorow bud.

lapsan

Berndt · « **Reply #10 on:** 7 Aug 2009, 04:02 pm »

Quote from: orientalexpress on 7 Aug 2009, 03:12 pm

sweet,i see u tommorow bud.

lapsan

I have some new metal you will like.
Metal in, metal out...

Wayner · « **Reply #11 on:** 7 Aug 2009, 07:43 pm »

Keep the motor positioned so that it is the farthest away from the cartridge when it is at the lable, tho it looks like your close, I'd move the motor more to the 10 o'clock position.

The Empire motor can generate some heat, that is why it came in a perforated winding cover. Now with more torque on it, there will be even more heat generated. Just hate to see you burn up that nice hard to find motor.

Wayner

Wayner · « **Reply #12 on:** 7 Aug 2009, 08:06 pm »

You are going to have a speed problem. Unless you kept the diameter of the underplatter drive rim the same diameter as the Empire's drive rim, the speed will change. You will have to make the pulley on the motor larger, however, that will increase torque requirements and put an even further burden on the motor. I thought the original drive rim diameter was close to something like 11.875" tho I have never measured it.

Wayner

Berndt · « **Reply #13 on:** 7 Aug 2009, 10:06 pm »

the platter drive diameter on the 398 (I think that's what it is), is 10.270".
I copied that dimension within .002".
The motor donor was from that empire, not a 208.
If this one works well there will be an empire 208 plinth and case for sale...

Wayner · « **Reply #14 on:** 7 Aug 2009, 10:27 pm »

Then you have done well, grasshopper! I knew the top was bigger from the photo with the 12" LP on it and your magnificent machining design didn't make sense if you didn't consider the pulley/platter ratio.

Then I woud say when you get the arm thing going, all should be well. Great job so far! Get some cooling on that motor!

I'll bet the table is going to be jet-black quiet!!!!!

Wayner aa

Berndt · « **Reply #15 on:** 11 Aug 2009, 03:36 am »

I swiss cheesed the back of the motor pod and now it just barely gets warm to the touch.
I checked the speed with a kab strobe and it was all whacky, I was starting to really freak out.
I then put a new battery in the strobe and we were back in business.
Running STP in the bearing really bogged the speed down, I couldn't get it to go fast enough so I changed to the lightest oil I could find, a 3in1 type oil and the speed is rock steady. WooHoo!
It requires retensioning the belt via moving the motorpod to get each speed to be kosher but that isn't a big deal. I am very glad the speeds lock in tight, the 208 I did has a slight cogging effect but this one is more steady.
I'll just have to leave the strobe disk handy. I am really looking forward to getting the tonearm, tie a string around my ankle so I don't float away.

TheChairGuy · « **Reply #16 on:** 11 Aug 2009, 01:45 pm »

You're about 78" of ill, boy....LOVE IT

John

Wayner · « **Reply #17 on:** 11 Aug 2009, 01:58 pm »

Goody! Sometimes the other oils have to thick of a viscosity to get the job done. 3 in 1 is actually the recommended oil for Empire platters and bearings.

Wayner

Berndt · « **Reply #18 on:** 3 Sep 2009, 03:24 am »

Tonearm is a project 10cc evolution 10" arm. I am breaking in a new sumiko blackbird as well.
The table just became playable last night and first impression is it does not have any glaring problems.
New tonearm, tonearm wire, and cartridge will take some time to jell up but what I am noticing is that the soundstage is taller now, about 3 feet taller than the speakers.
Going to be inspired to host a get together once the sound jells up.
Sorry 'bout the crummy pics will do some day time shots with a bit better resolution.
Regards,Bill

James Romeyn · « **Reply #19 on:** 3 Sep 2009, 04:00 am »

The TT looks fantastic; a mix of art novue & what Harrison Ford would own in Blade Runner.

Scheduling get together after my guitar's ETA (17 Sept) would allow attendees to hear your TT & a flat top w/ performance similar to this http://www.dreamguitars.com/preowned/klein/klein_s4_048/klein_s-4_048.php