Supersom Mono Cutterhead

[Babooino]

Hi, im new! Great board! I just bought a Fairchild cutting lathe and will be around from on!
Well, i need help from you guys to try to identify this cutterhead? Any info?

Best regards, Anderson

[studiorp]

Hello, welcome!
Intertesting cutting head, never seen before...; there is the brand and model probably in front of, but the photo isn't clear .
Can you do another photo with the plate of brand ?
Thanks.

[Babooino]

Hi, thanks!
The brand is "supersom", and old local electronics dealer.
Actually i want to get some details about it.
I believe this is a mono head, right?
Why there's two connectors? Any leads?

[EmAtChapterV]

Take impedance readings of both plugs once they're cleaned up. One of them should read around 5 to 16 ohms (if the front label is correct), that'd be the drive coil. The other one, if it reads an open circuit it's probably for the heater wire; if it reads something other than open, it might be a feedback head.

[studiorp]

I have discovered that Supersom was a brasilian brand of hi-fi components probably 1960-70 years.
Here a beautiful ( never seen before ) reel to reel recorder

http://i285.photobucket.com/albums/ll57/LocatelHT/Supersom.jpg

[Babooino]

Thanks guys, great tips!
Also, im having a hart time connecting the gearbox back together, does anyone have any documentation or pics on this?

[Babooino]

Oh..i forgoto to mention it came without the motor. What should i be looking for?

[studiorp]

What model of Fairchild do you have ?

[Babooino]

I thinks it is a 523....but i'm not sure. The tuntable that came with it, is a 3 speed supersom. It has its own motor. But the gearbox is missing the motor, so i dont know exactly what i should be looking for...

[mossboss]

This is purely deductive from what is shown in the photos as I do not have a lathe that's the same or even seen one
I think you are looking for is the other half of the gear box as well as the motor as there is no drive shaft visible and I don't see how speed choice can be achieved as this is the shaft that drives the crown wheel or the angle drive gear
Where you have your thumb If you push the spindle or move the lever you most likely you see the dogs on the gears engaging one another shifting/sliding on the splined shaft
It seems that the motor had a matching set of gears engaging the gears in what you are showing in the photos as it seems that this is the main shaft of the gear box to be driven by another set of gear or gears
It is a typical gear box layout of the 30's to 60's used in a lot of equipment so don't be surprised to find it in other pieces of equipment not necessary lathes, may be you get lucky and find it where the lathe come from at least the gear box and shaft any way if someone took the motor for some other use it may still be around
If not than you May be you would be better of forgetting all of that and get a DC motor with speed control unless you can put your hands on the missing half
Best of luck with it

[Babooino]

Thanks Chris!

Is there any specification on what kind of DC motor i should get?
I don't think i will ever get my hands on the other half of this thing.
It was stored in a warehouse, and looked around for hours but didn't find anything.
My friend who is the previous owner, told me it has been there for decades...

Well, i'm starting to restore it. Rafaello(studiorp) has been helping me a lot answering my noob questions..

Here's some turntable (also Supersom) picture, before and after resto.

Anderson.

[mossboss]

This is a solid gear box so you may be able to use it
Maybe you take the housing off as well as the gears than see how the shaft is mounted to the crown wheel
It would have a bearing in there so if you can get a pulley or even turn a v groove on one of the gears you can drive the shaft with a reasonable motor
By the way do the gears slide when you move that lever? Or they stay in the same position?
May be there this is a hollow shaft where the gears are mounted the shaft with the little round spindle sticking out in the photo where your thumb is may be what engages the gears
It may have a little grooved steel ring and pushes some steel balls through the hollow shaft therefore engaging the gears
You need to investigate it a bit more may be pulled it bits and post up some photos
By the way don't you machine up the TT Plater like Rafaelo did OK!
Cheers

[studiorp]

Dear Mossboss, I have done this modify because my platter was more heavy for my dd drive tt; ok you know that in system where there is a platter driven by a belt, more heavy = more inertia; too I had experimented this solution, fantastic, but there are speed flutters; the same with idler system.
I wanted the speed perfect, so I have adpted my heavy platter to rest of machine, and now it's all perfect.
When you will see my photos, you will understand many things.
Cheers.

[Babooino]

I've opened it up to clean and surprise, that thing is brand new inside. The gears look like they have never been used and even the oil is new. After a little cleaning and lubing outside, everything moves like it should and the gears are engaging fine. I think this thing is 2 speed, probably 33 and 78...
It uses 3 belts but 2 gears are same size. The little spindle engages the small gear when its pressed down and the bigger one when i release it.

Well, but as long as i am use a new dc motor i think i will be using this gearbox only as a reduction stage and will calibrate speed electronically, right?. Question is, my TT already has a motor in it and it's running fine in all 3 speeds. Can i run the system with 2 motors or both things should be synced?

[studiorp]

Your dc motor has been built with brush, or it's a type brushless ?
Brushless is better, less vibrations. This is an important point if you want obtain silent grooves on your discs. I have changed 4 times motor system before to obtain total silence !
The two systems can be synchronized ( as my case but with a alu pulley reduction speed ) or separated.
If separated you can for example work to 33 rpm on your turntable and change the speed on your lathe, for example 10-15rpm.
If you change the speed on your mechanic, then you can obtain a diverse time recording.
In each case the 523 mount already the lpi change system, so must decide you what do.

[mossboss]

Dear Mossboss, I have done this modify because my platter was more heavy for my dd drive tt; ok you know that in system where there is a platter driven by a belt, more heavy = more inertia; too I had experimented this solution, fantastic, but there are speed flutters; the same with idler system.
I wanted the speed perfect, so I have adpted my heavy platter to rest of machine, and now it's all perfect.
When you will see my photos, you will understand many things.
Cheers.

Hey so long as you are happy man that's all that matters and you are cutting good sides
By the way every VMS Neumann out there has a direct drive and it takes a strong man to lift the cast bronze platter off and it has another not so heavy aluminium platter on top of it as well
As a guess about 20-25 odd kg in total
And the lyrec lathes had a heavier one than that about 30 + odd kg
But so long you are happy it's all that matters
Cheers

[studiorp]

Yes, I am agree with you, the important is be satisfied and obtain good result for a not pro lathe.

[Babooino]

What is the advantage of the dc over ac motor?

[studiorp]

With a dc motor you can regulate the speed, as you want; with an ac motor you can't change the speed, unless you have a special inverter built for ac motors...

[Stevie342000]

Hmmm I am not sure that statement is strictly true with a DC motor you vary the volts to vary the speed with an AC motor you have to change the frequency to change the speed. Either way it is done electronically.

When these types of turntable drives were in vogue, they relied on sheer mass to keep wow & flutter down and speed change was done by gearing. It was simpler electronic control would not have been so simple back when these were designed in the 1930s.

It relies on high precision engineering, there are a couple turntable motors of the type that were used in similar turntables check out the classifieds its a few weeks back. Or alternatively http://www.ebay.co.uk/itm/121063823445?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649