If there was enough interest, I'd be prepared to do a run of these. Please see earlier in the thread to see the standard of my version. It also improves on the original in a number of ways-including the adjustable headshell arrangement which makes azimuth and offset angle adjustment a doddle.
I've been using this version for a couple of months now and have to say it's one of the best I've used (if not THE best!). So much so I've almost finished another to use on my slate plinth Garrard 401.
I recently advertised my version and have quite a bit of interest. One person thought mine looked superior to the original. Another person who bought a deck (another 401)without arm from me in the summer was amazed at how good the arm was!
So-there you are-if there is enough interest, I'll produce a short run of them. Any thoughts on price anyone? Remember I consider this superior to a number of arms I've owned-Kuzma, Hadcock, Wand, Morch, Audiomods etc.
Regards
Chris
I've been using this version for a couple of months now and have to say it's one of the best I've used (if not THE best!). So much so I've almost finished another to use on my slate plinth Garrard 401.
I recently advertised my version and have quite a bit of interest. One person thought mine looked superior to the original. Another person who bought a deck (another 401)without arm from me in the summer was amazed at how good the arm was!
So-there you are-if there is enough interest, I'll produce a short run of them. Any thoughts on price anyone? Remember I consider this superior to a number of arms I've owned-Kuzma, Hadcock, Wand, Morch, Audiomods etc.
Regards
Chris
Sorry if this has been answered before (I have searched for answers!) but I have a question about the earthing/grounding of the arm. I am planning a copy of the WTA (disc paddle not golf ball) using aluminium for all the components. I can see lots of images of the four cartridge wire entering and exiting the arm tube, but I cannot see any wires earthing the arm or any of the components, except the 4mm grounding post on the terminal block.
How is the arm earthed? Does it need to be earthed? Is it beneficial to run an earth wire from the headshell to the terminal block?
Sorry if the questions seem naive - I'm just starting out!!
Thanks!
How is the arm earthed? Does it need to be earthed? Is it beneficial to run an earth wire from the headshell to the terminal block?
Sorry if the questions seem naive - I'm just starting out!!
Thanks!
math/science detour (fun at least i think so)
i have been reading this thread and several others linked to it and decided to see if i can still perform a little math / science (hey its a slow monday at work)
history: why golf balls have dimples. to acheive turbulent flow with a smooth sphere it needs to be traveling ~ 200 mph (way above what humans can acheive). adding dimples induces turbulent flow (lowers drag) at a much lower speed therefore increasing the distance a 'normal' human can hit the ball.
science: viscous flow. typically this is expressed in terms of reynolds number which relates the density of the medium, mean velocity, size and viscosity and indicates if the object continues to move due to intertia (high reynolds number) or if the medium exterts a large drag force (low reynolds number).
Re = rho * speed * L / viscosity
For the WTL Tonearm rho = 760, speed (really small), L ~ 0.04267 m (dia of golf ball) and viscosity = 10000 (earlier post, later posts have 100000) so we get Re = 0.00159 * speed, or a really small reynolds number (a duck flying 20m/s has a Re=300000).
There is a field that studies very low Re (interested in microorganism motion in fluids) which basically states their motion is extremely damped by the fluid (yeah what we desire) so +1 for the silicon fluid.
Now the ball & dimples. the increase in area due to the dimples is ~ 1-3% (see attached matlab script), not really that much so a smooth sphere of the same size should have the same drag properties as the golf ball. my assumption is that the golf ball was just handy.
So bottom line:
golf ball is nice weight & size to make life easier, low velocity and high viscosity fluid damps motion quickly so this becomes an excellent method for a tonearm.
That all being said i am heading to my local hobby shop to pick up the materials to make one
i have been reading this thread and several others linked to it and decided to see if i can still perform a little math / science (hey its a slow monday at work)
history: why golf balls have dimples. to acheive turbulent flow with a smooth sphere it needs to be traveling ~ 200 mph (way above what humans can acheive). adding dimples induces turbulent flow (lowers drag) at a much lower speed therefore increasing the distance a 'normal' human can hit the ball.
science: viscous flow. typically this is expressed in terms of reynolds number which relates the density of the medium, mean velocity, size and viscosity and indicates if the object continues to move due to intertia (high reynolds number) or if the medium exterts a large drag force (low reynolds number).
Re = rho * speed * L / viscosity
For the WTL Tonearm rho = 760, speed (really small), L ~ 0.04267 m (dia of golf ball) and viscosity = 10000 (earlier post, later posts have 100000) so we get Re = 0.00159 * speed, or a really small reynolds number (a duck flying 20m/s has a Re=300000).
There is a field that studies very low Re (interested in microorganism motion in fluids) which basically states their motion is extremely damped by the fluid (yeah what we desire) so +1 for the silicon fluid.
Now the ball & dimples. the increase in area due to the dimples is ~ 1-3% (see attached matlab script), not really that much so a smooth sphere of the same size should have the same drag properties as the golf ball. my assumption is that the golf ball was just handy.
So bottom line:
golf ball is nice weight & size to make life easier, low velocity and high viscosity fluid damps motion quickly so this becomes an excellent method for a tonearm.
That all being said i am heading to my local hobby shop to pick up the materials to make one
Interesting reading,
I have also read about the 100 000 rating as well! And going for a longer arm I may have to order some more.
I have dampened my arm down from the pivot point back with chalk and are extending the length back past the pivot point quite some distance to reduce the need for a heavy counter weight. My current weight is around 12 grms.
Anyone have any thoughts on that?
I have also read about the 100 000 rating as well! And going for a longer arm I may have to order some more.
I have dampened my arm down from the pivot point back with chalk and are extending the length back past the pivot point quite some distance to reduce the need for a heavy counter weight. My current weight is around 12 grms.
Anyone have any thoughts on that?
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Is'nt there at least some sort of concensus, that the counterweight should be as close to the pivot as possible? This relates to the effective mass of the arm, and moving the weight away from the pivot, will increase this accordingly. Could be interesting to hear about your findings. What cart are you using?
Steen
Dyolf,
Thats always been my understanding that the closer to the pivot the better for C/weights.
harperrc,
Cant read the golf ball txt.
What part of AL are you in, I lived in Montgomery for a few yrs.
On the golf ball dimples…… if each dimple was drilled a bit deeper would it then cause more drag.
No I'm not going to drill them
Side issue, anyone use Decca cartridges ?
happy holls
Thats always been my understanding that the closer to the pivot the better for C/weights.
harperrc,
Cant read the golf ball txt.
What part of AL are you in, I lived in Montgomery for a few yrs.
On the golf ball dimples…… if each dimple was drilled a bit deeper would it then cause more drag.
No I'm not going to drill them
Side issue, anyone use Decca cartridges ?
happy holls
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don't have word on my macbook pro.
Didn't think it would be of any benefit to the amount of drag caused.
I believe its more to do with the viscosity of the fluid.
The dimples & the golfball are a happy coincidence, that Fairbrough found to his advantage & ours of course lol
It's my understanding that JW has a rather quick turn around of a week, or two at most
& a bit cheeper for what he does..as I think he deals exclusively with Decca's, All types.
He's also the one that most likely made them in the first place.
Didn't think it would be of any benefit to the amount of drag caused.
I believe its more to do with the viscosity of the fluid.
The dimples & the golfball are a happy coincidence, that Fairbrough found to his advantage & ours of course lol
It's my understanding that JW has a rather quick turn around of a week, or two at most
& a bit cheeper for what he does..as I think he deals exclusively with Decca's, All types.
He's also the one that most likely made them in the first place.
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