Redesigned Nakamichi classic tape transport.

20tajk7

20tajk7

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You never have too much tapedecks ^^
Well, occasionally there's interesting things on fakebook, but that's drown in an ocean of crap and misinformation.

So what does the Nakamichi guys thinks about this modification ?
Nakclassictwobelts.png
 
did the guy also change the shape/dimensions of the flywheels or did he only increase the weight?

but, the main question is: did he just try and test how it really works?
 
Hell if he got it going again with all those problems he done better than I could have so I vote him up !
 
To be fair, unless you personally have access and experience in producing something like this, then his solution although desirable, is not cheap or practical, unless he's gonna spin up some extra ones and make them available cheap! [...unlikely]
My ol' 700 hasn't had it's belts done in 40 years, and obviously due for a change even tho' [sadly] I never use it, so if I stick in some new ones, then it should be good for another 40 years.
I'll be long gone by the time they wear out...
 
I'd have to see more technical details on a lot of different levels to see if this mod even warrants a response.

And I agree PD... these marvels of analog tech have lasted for decades. Do they really need redesigning now? Highly doubt it.
 
If it's an improvement, why not. There are a lot of mechanical parts in our gear that if price is not much of a concern, as in , more of a " what if" mode, go for it.
 
Don't get me wrong Lee, I'm all for tinkering or even redesigning for the pure fun or sport of it.

But labeling the problem in this particular case - a Loop - begs a lot more questions... in addition to knowing a lot more details on how the overall 'system' performance was impacted. For Naks, is poor tape tension really a mechanical problem or something electrical in nature - on sh!t this old.
But whatever...

Not for me to dictate how people spend their time.
 
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The big flywheels remind me of a Studer cassette transport a bit.

It seems the cassette is going the way of the turntable, where “bigger is better” with massive plinths and platters…

Fix one problem and create two new ones.
 
vince666 said:
did the guy also change the shape/dimensions of the flywheels or did he only increase the weight?
Click to expand...

That would be interesting to know. If dimensions/shape are as original, then the material used is just 30% denser and inertia 30% higher than original. If not...well, there's the posibillity that inertia actually decreased despite the higher weight. The shape (distance of mass to the point of rotation) influences the moment of inertia by power of 2, mass does it linear - twice the distance, four times the inertia...twice the mass, twice the inertia.

I like the execution, though.
 
oh yes, inertia goes indeed with power of 2.:D

inertia momentum of a certain body/shape needs integral calculus, not just the easiest thing to do, but the classic Huygens-Steiner formula to get inertia on a different axle just tells us about the power of 2 behaviour... but, of course, regular shapes make a lot easier to calculate it

funny that you quoted me and talked about this.
I actually love this specific matter (geometry of masses)... at the end of the 90s, while studying it at university here, i happened to find a brand new formula regarding the "nocciolo centrale d'inerzia" of a generic surface (don't know the exact englishname of it) to calculate its shape also when you don't have those easy/regular shapes like squares, circles and such.
 
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Enzo, yep.

Actually...if I recollect correctly, you intend to pick up studies again. I immediatelly thought of what your thesis should be about: Turntables - the misterious interaction between effective mass/lenght, compliance (given at 10 and 100 Hz) and resonant frequency. :eek: Oh dear, the neverending story.

Back to topic... Chrome-plating seems a good idea (to me at least) as it doesn't tarnish/oxidize, so the belt-flywheel friction/slippage should be rather consistent over time.
 
borchee said:
Enzo, yep.

Actually...if I recollect correctly, you intend to pick up studies again. I immediatelly thought of what your thesis should be about: Turntables - the misterious interaction between effective mass/lenght, compliance (given at 10 and 100 Hz) and resonant frequency. :eek: Oh dear, the neverending story.
Click to expand...

you recollect it correctly.

and, yes, that would be an interesting topic for a ME thesis.
 
It would have been simpler to get rid of the too tight belt, which causes looping, and install a good belt. Increasing flywheel mass lowers the flutter frequencies due to belt stretch. I also bet he used an undersized supply flywheel to create back tension. Unfortunately, the deck alredy has the correct back tension, so all this chap has done is to increase head wear.
 
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