Frank-O-Kut Project...

[thebutler]

If anyone is interested, thought I would post my progress of a Rek-O-Kut TR43H based fraken-lathe...

Inspired by it's logical simplicity I feel quite bad modifying with modern components, I'd love to restore it to all it's original Mono Glory, perhaps a project on something a little more worthy in future...

Anyway... my main goal here is a learning experience before possibly moving onto a purchase of a "real" lathe, but I'm quietly confident I can achieve some good results as this stands. It's also inspired me to look at modern, digitally controlled alternatives that would be able to achieve higher accuracy across all movement axis... another project for another topic however.

I'm attacking this from all angles... [motorised] variable pitch, fully adjustable brushless DC platter drive, decent [stereo] playback path and perhaps even a remotely adjustable depth control will be the highlights, in theory.

Here's the base machine, bought on eBay a few weeks ago...

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... more to follow shortly ...

[thebutler]

I'm 3 weeks into this now, and although I have been slowed by surgery thanks to my appendix nearly bursting last week, and the subsequent haze of prescription medication, I'm close to mended and almost ready to continue... here is my progress anyway;


My first observation and concern was the resonance and [lack of] strength within the case itself; so, I hand cut a bracing structure inside the main "suitcase"...

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... and on the face plate ...

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... also added the appropriate Vibrapod underneath ...

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[thebutler]

Next step was to get my playback path locked down... quickly received some nice components from Esoteric Sound, a couple various HiFi stores, and the super nice guys at CineMag who wound some balancing transformers for me for my phono stage.

I went with CineMag after seeing them in the new release Foote Control P3S ME compressor... very cool comp BTW.

The new Rek-O-Kut 16" tonearm...

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Mounting [surprisingly] took me a whole day in the end, had to raise the mech for optimum angle but turned out great as the piece I decided to use was a solid rubber "puck" I cut out from an old isolation tool in the studes... so the whole thing is super isolated now...

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Here she is installed...

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[thebutler]

Sorry for the spam! Last one for now, shot with my new little component video microscope too...

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Next up, while I'm stuck on the couch... overhead clean and re-build...

[thebutler]

65 Years of Dirt...

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Disassembled the entire overhead, washed each component by hand in a few different stages of soapy water...

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Absolutely in love with the mechanics & design of these old lathes, haven't been this inspired since my studio build

[thebutler]

After some lubrication and replacement washers, back together with a huge colour change...

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[Angus McCarthy]

Shiny!

[tragwag]

beautiful, great work!

[thebutler]

Thanks guys

I've been going round in circles on what to do with my drive motor... I'm close to pulling the trigger on a brushless AC motor... only going AC as the speed control specs of this particular motor are much better than their DC counterparts, max fluctuation (under varying load) is +/- 0.02%. It has a digitally controlled adjustable speed drive with enough range (and useable torque) to work with either a rim drive set-up or if I decide to modify the platter, then direct drive is also possible. It's expensive, but has 40 kg/cm2 torque and the digital control will really give me the ability to dial in exact speeds, including half speed cutting which appeals to me in theory.

In my head, rim drive seems to be a better option than direct as far as vibration/noise induction anyway. I'll be able to rig it on an isolated mount, then the only contact point with the platter itself is the flywheel of some type... probably the existing stock 45 to start with... it's rubber... adjustable pressure to rim, and therefore less induction of noise no?

Only other way I can think of for direct dive is a flexible coupling, but I'm sure the rubber will be pretty tough, and therefore induce noise anyway. The motor has very low specs as it stands, so maybe it's not a problem... hell, every VMS is direct drive.

I'm trying to stay away from belt drive... the platter isn't very suited to it, and I'd like to keep as many of the modifications as hidden as is possible.

I actually do some casual acoustic design (EASE modelling) for a distributor in Aus, they used to be the Stanton agents and have some of their motors available... 4.5kg/cm2 just doesn't seem like it will cut it to me though, and speed adjustment isn't enough as stock.

Sorry for the rant... Any thoughts...? Am I way off base here?

[studiorp]

I have changed four times the motor system before the find the right .
Now I am with a high torque quartz dd motor. Yes, I am agree with you, will be more work modify all lathe with this system, but if you want no wow and flutters on speed, it's the only system .
The rumble of a dd motor during cut is more less than a dd turnable for playing records, but this is linked to cut pressure; more pressure cut , more rumble ( in my case, but perhaps because I have a cast iron platter ... ) .

[thebutler]

Thanks studiorp ... something to think about.

My brain is running overtime ordering components to automate my pitch at the moment. Currently cheaper than an eBay leadscrew or overhead mech... if it works, ha.

[jukeboxje]

i used a mechanism from a seeburg jukebox with a frequency control

[Jccc]

Hello awesome set up and restoration going on here. I have a question.

What are you using for your microscope? I am currently in the search for one and yours looks pretty awesome.
Did you hook it up to a microphone stand?

[thebutler]

Not sure of the exact model, but the microscope is a "Dino-Lite". It was a little difficult finding one that wasn't USB, but they are out there.

I didn't want to have to run a computer for it to operate, so bought one with a component output... strapped to a computer LCD and you're away. Resolution isn't that great, and the lighting is somewhat annoying also.... but it's a good start. The whole thing (including a refurbished LCD) cost me under $200 delivered.

And yeah, I've got it on a mic stand. It fits perfectly in the [larger] Shure wireless mic clip

[thebutler]

Tried out some miniature linear actuators, they were all either too noisy, or far too large.

Think I may have a proof of concept that will work though... utilising a pulley system and a whole bunch of robot geared components. Parts for days...

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[thebutler]

View from the front is not too obtrusive... here's a pic of a mock up using all existing mounting points. Looks like I may get away with the full install without a drill, or single modification to the overhead.

Obviously need to mount the motor, and I'll also be adding a geared worm drive for more accurate motor speed control.

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[uvoscillator]

Hey ! Any updates on the project? Very interesting ! I'm also setting up my TR43H now, so any drops of information is useful )

[thebutler]

Yeah, made some decent progress, just been too busy to post. Sorry!

Pitch system is working, although I'm craving something larger... experimenting with drive wheels at the moment, but the new motor is a beast and working well.

Will get something up over the weekend!

[tragwag]

I'm trying to get an alternate feedscrew drive working with my Presto 6N, any suggestions?
I've got some ideas, but not nearly enough experience with motors to have a solid place to start.