You wanna innovate? Make a good hi torque turntable

[Steve E.]

You wanna innovate? Make a good hi-torque turntable.

I am aware of several people on the forum prototyping "new" overhead systems for cutting. This is awesome.

I may be missing someone's efforts, but there exists no currently-produced turntable that can provide sufficient torque to cut records without introducing warble into the recording.

The Technics SP-10 MKiii (or SP10 mk3) had a 48-pole motor and a 13 lb torque. (This is similar to the Technics SP-02 [SP02] which was designed specifically for record cutting.) These are extremely difficult to find, and expensive as hell when they do show up.

So, make wunna those. And make it quieter than a Presto.

http://forums.stevehoffman.tv/threads/anyone-have-specs-for-technics-sp-02-turntable-lathe-motor.149992/

EDIT: Upon reflection, I think referring to a random thread on the Hoffman forum for my info on these Technics turntables is sloppy research. I am NOT certain that I am correct. Elsewhere on the internet, I found debates on whether the SP10 Mkiii was a 20 or 24 pole motor. I don't even know the specs of the SP02 [SP2]. It would be great to confirm these specs.

FURTHER EDIT: Evidence now suggests that SP10 MKiii and the SP02 had 15-pole motors. (Maybe the Mkii did, too?) This is talked about in various threads.

[ROLANDJAYS]

I have thought about it . But once I did the math on cost, I figured its to expensive and not many would buy..... anyone else ..... ??

[Stevie342000]

There are two d-i-y designs for a belt driven turntable featured on in a couple of editions of Radio News which you can find here: http://www.americanradiohistory.com/Radio_News_Master_Page_Guide.htm

Which should suffice for anyone desiring to cut there own records or replay them. The issues you need to look for are December 1943 and March 1953 the articles are on page 10 and page 68.

Its not necessarily all about torque more a case of inertia, you will need a degree of torque to get these spinning but it is not the only thing, even a Neumann relies on inertia not just torque.

[dubcutter89]

I've already posted it once on the forum, not sure if it is already available:

http://www.flokason.ch/fs_directdrive.html

...and if you don't need your Lyrec anymore feel free to contact me!

[opcode66]

Already on it....

[inspector77]

Already on it....

you never sleep!!!

[gauze]

I had an old Dual turntable that had a heavyweight platter something in the neighborhood of 7.5lbs, I think that would be the easiest method to get good inertial stability.

[ROLANDJAYS]

I've already posted it once on the forum, not sure if it is already available:

http://www.flokason.ch/fs_directdrive.html

...and if you don't need your Lyrec anymore feel free to contact me!

this one look pretty good.
I would buy
but I wonder how much it would cost ???

2000$ or 5000$ ???

[opcode66]

It might take some work to make that drive system cuttable on anything other than a VMS.

Also, there is no projected availability on that project. And, my guess is that it will in fact be more than 5K. Probably more like 8K to 10K....

Mid grade cutters don't need that. We need a mid grade solution that is reasonably priced and available. I'm hoping to collaborate with someone making platters. I've been working on various bearing system and linkage ideas.

Currently, I have a plinthe for testing, bearings, linkage, motor mount, motor, motor control and speed selection worked out. With BLDC motor. Been trying to work out the last kink between projects. I've been using a spare platter from a 1200 to test with. Code named Scooty-Turn Jr. Once it works well, I step up the motor size and make Scooty-Turn Sr. Then I work out a proper mount for a VMS system and we get to the Opcodious Maximus.

[Gus]

Here is
I don't know how many kgf.com
but the platter weighs 3 kg

some infos:
http://www.langer-audio.de/Page15.html

owners manual pdf

http://evolution-audio.de/assets/bedienungsanleitung-langer-no7.pdf

price list

http://evolution-audio.de/preisebestellen.html

[ROLANDJAYS]

I cant read this language. I don't see any specs in numbers.
help......

[opcode66]

3,450 Euro

I can read that spec....

[Gus]

some infos in English

Langer Direct Drive
Solid motor design combined with innovative speed control.

Motor:
The motor design is brushless. It used Hall sensors and an integrated electronic board for commuting the motor coils. This is a must for a smooth motor movement and for elimination of distortion by usual brushes. The motor coils are air core types. So there is no magnetic rest point or hysteresis loss. An optical sensor is used for continuous speed feedback.

As the motor bearing is also the platter bearing, we spent special attention on its design. The radial force is carried by a precision sinter metal bearing. For the axial forces, we spent the motor a bearing bottom out of polyamide. This design guarantees very low noise movement and high precision bearing gap, combined with long life.

The rotor unit is also a sub platter. So it is easy to combine with al kind of platter designs. All motor components are integrated is a solid metal housing, which eliminates all kind of vibration.

Speed Control:
For our "langer" motor, we designed a special speed controller. This controller is an analog design. That means we use an analog signal for the motor speed feedback and compare it with an analog reference. The output signal to the motor is again analog. In combination with a correctly designed platter, the signal to the motor is a simple line, absolutely low level and flat. In normal drive condition, the motor acts just as a precision bearing plus a little energy for the friction losses. Only in start mode or at higher break forces, it increases the drive current accordingly to the needed level. Long waiting times for stabilized platter speed as a compromise for low wow and flutter and low noise, is no longer needed. The "langer direct drive" features both without compromising.

Components for DIY and OEM partners:
We do not use our drive technology exclusively only in our turntables. We also offer them as components for high quality DIY projects or OEM partners. The integration of our technology in other projects is very easy by design.

Price : 3,450 Euros

[Gus]

specs

[recordboy]

My DIY thought (since I am also a sculptor & machinist) was to take a potter wheel and attach a lathe motor to it... That's how I am figuring to make mine (once I have the space. Maybe/Hopefully this year). Talk about torch and Inertia... Also from what I've seen ov the old big cutters. They pretty much use this technique.

-cheers

http://www.motherearthnews.com/diy/pottery-kick-wheel-plans-zmaz70ndzgoe.aspx#axzz3O6KxdjF3

[Sillitoe]

I have just finished stripping two large billboard printers for parts and have acquired 13 brushless AC servo motors and drivers among other things.

7 are Baldor BSM90B- 3150AA Specs- http://www.baldor.com/products/servomotors/b_series/BSM90B375AA-to-BSM90B3250AA.pdf (middle one).
3 are Baldor BSM90B- 2150AA Specs- http://www.baldor.com/products/servomotors/b_series/BSM90B275AA-to-BSM90B2250AA.pdf (middle one).

The others seem less suitable (faster rpm etc)

The drivers are 230V single phase-
Baldor Flex Drives-
FD2A05TR-RN20 (x5)
FD2A07TR-RN20 (x3)
DBSC105-GAAW-2 (x2)
Control Techniques Unidrive V3 UNI1405 (x4)

I have a bunch of reduction gear heads with ratios of 5/1, 8/1 and 12/1 to slow them down a bit...

From what I've read they seem to fit some of the requirements but does anyone with a bit of knowledge and experience think these would be suitable for decent TT motors?

Thanks!

[markrob]

Hi,

Probably vast overkill, but you got them for free! I assume you also have the drives. I don't think you will need the gear reduction as 2000 rpm is in the range of most belt driven turntable motors. If you are going direct drive, then they may be needed. I would be concerned that the gear reduction might be noisy in a direct drive arrangement. For a DIY project, I think belt drive might be easiest to work with as you will be able to better isolate the motor vibrations from the platter.

Mark

[Sillitoe]

Hi Mark, I was hoping you'd reply!
Yeah free so I thought I'd ask
Yes I do have the drives too.
I was initially thinking direct drive, some of the gear heads seem very smooth and quiet so I might give it a go and post back with my results.
What do you think would best dampen vibrations? I have flexible shaft couplers but maybe I'll try a Scully oil kind of thing? (although I don't have a full understanding of the Scully platter/bearing mechanism).

Cheers

[Sillitoe]

I managed to hook up one of the Baldor BSM90B- 3150AA motors to a FD2A05TR-RN20 drive and have rpm ranging from 0.3rpm to 2000rpm, wow.
These motors seem perfect for direct drive (without need for gear-heads).
I bought a KAB speed strobe and the setup measured stable to the strobes best performance of 0.03% at 33.3 and 45rpm, well above the nab recording standard.
This thing has amazing inertia and I can't slow down the shaft by gripping it with my hand, it shows no speed variation at all.
At the moment I have just bolted an LP to the end of the motor shaft and then sat the strobe disc on top of it for testing.

I'm going to use one of these motors on my second lathe (the brown one) instead of the SP10MKII.
I will post a video when I am further on with the project, so far I've got the thrust bearing and housing and am looking into a 14 inch platter, shaft/sub platter and fluid coupling system.

The setup is pretty quiet and the motor shaft has very low vibration, the drive makes about the same noise as my imac with the fan running at full speed.

[piaptk]

Peter King supposedly built two of his own lathes using motors from washing machines. Well, that's the legend, anyway!