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[j.b.c.]

Inharmonicity is not usually a problem with free reeds.

How is this possible if the tuning of the reed is influenced by its surrounding cabinet?

One would think that the Helmholtz effect of the cabinet shifting the pitch of the reed is the very definition of inharmonicity.

[Rog]

"When working to Dedic/Viennese tuning, you can't easily tune octaves by ear becausE.."
Yes of course you are right. However, how would a tuner achieve Viennese style tuning, with M- and M+ reeds, before strobe tuners? Maybe start with two M0 reeds and flatten/sharpen equally,  by comparing to a third M0 Reed?

[malcolmbebb]

One might suggest that most cabinets don't have walls that are constantly moving in and out and changing their shape. And on the reed block side, the distances are very small compared to the sound wavelength and the air pressure constantly changing, so setting up a resonance might be tricky.
The volume of air in the cabinet is being controlled and varied by the bellows to an extent far in excess of the effect of the sound waves.
Of course it all depends on the wood...

[Winston Smith]

And the other Melnetters were astonished at the pure simplicity of Kimric's tuning bench.

[Anahata]

One would think that the Helmholtz effect of the cabinet shifting the pitch of the reed is the very definition of inharmonicity.

Not at all. Inharmonicity means the harmonics are not exact integer multiples of the the fundamental, and effects that shift the pitch of the reed shift all the harmonics in step with the fundamental. In pianos, inharmonicity is caused by end effects: the effective length of the string is not the physical length, and the effective length for the second harmonic, for example, is not exactly half the effective length for the fundamental.

The real reason why free reed instruments don't have this problem is that the sound that you normally hear comes from the airflow being chopped by the reed alternately obscuring and opening the slot. The harmonics of the sound that you hear are caused by the chopping of the airflow not being sinusoidal (presumably more like a soft edged  square wave) and they are exactly in step with the fundamental.

If you press the reed block to your ears and ping a reed, you will hear the harmonics of the reed's vibration itself, and there's a good chance that they will not be in tune with the fundamental, but those out-of-tune harmonics have very little influence on the chopped-air waveform that you hear normally.

[robotmay]

Currently I'm tuning at my desk entirely inside the melodeon, which is not exactly a very time-efficient way of doing it, although whilst I've been learning it has been rather good to do the entire process in the simplest way possible. Hoping to eventually have a space where I can set something up, and I'd love to experiment with various electronic doodads, mostly because I'm a programmer and that just sounds like even more fun

Here is a video I published in 2014 of my ‘alien’ tuning table (well before the AKKO table was introduced I believe).
https://youtu.be/un-AvLaCenU

My YouTube channel showing some of the hundreds of button accordions and concertinas I've tuned using it:
https://www.youtube.com/user/buttonboxbellinger/videos

It can be used with single reedplate fixtures, reedblocks (single, double or triad chords) or full in-situ (without bellows).

I was thinking about this sort of system just a few weeks ago, and this looks really tidy. I also love the look of that gimball-desk-vice you've got on your worktop. I have a small vice like that but I can't adjust the angle; that thing looks really handy!

[hickory-wind]

I was thinking about this sort of system just a few weeks ago, and this looks really tidy. I also love the look of that gimball-desk-vice you've got on your worktop. I have a small vice like that but I can't adjust the angle; that thing looks really handy!

I have another swivel vise for waxing. I lined some angle aluminum with felt and mounted it to a low profile version of the vise.  This allows 360 rotation and more than +/- 50 degrees of tilt so I can position the reedblock any way I like while waxing the reedplates. Usually I tack-wax all reedplates in place with a little dab top and bottom. I then check all reeds (blow & suck) on my air table to make sure all reeds are sounding and all valves (inner and outer) are functioning before going back and final waxing. I'm attaching a photo from the top. You can see the tack-wax dab on the top of the reedplates. This photo looks like a staged photo for my website since the two open cavities still have the old wax not scraped off... not my normal procedure.

Scott

[hickory-wind]

Here is my next generation waxing jig showing the universal base. Also visible are my wax sticks (I made a split mold for casting) waxing iron and high velocity German fume extraction so I don't breathe the nasty wax fumes.

Scott

BellingersButtonBoxes.com

[Nick Collis Bird]

Scott, is that a slice of Salami to the left in the top picture ? 

[Rog]

I’m really old school when it comes to waxing. I’ve got one of Carini's wax pots and a very long spoon like the one Charlie sells. I hold the block so I can move it around and cause the wax to flow. And a very bright light so I can see what I’m doing   I don’t generally have salami on the bench. Biscuits have been known to be present sometimes.

[Winston Smith]

Serious thread drift here, but I'm sure that members would be interested to see our favourite bookbinder taking his first driving lesson, he's hardly changed, has he?

[Pete Dunk]

Scott, is that a slice of Salami to the left in the top picture ? 

Looks like a pan scourer to me.

[Theo]

[[ADMIN]]

Salami, pan scouters, driving lessons?  This topic has run off the road!