Scrap bellows

[VIN]

Apologies for what is I’m sure an old chestnut of a question, does anyone have a set of old bellows that could be used in the making of a tuning bench that I might buy, il happily pay the postage obviously, many thanks, vin

[AndyNT]

It is relatively easy to find unwanted old piano accordions bring given away for next to no money. 

As well as donating bellows, their many reeds are good for practising your tuning skills before approaching a concertina.

[David Lay]

I bought old accordion reed blocks from Liberty Bellows in PA to get tuning practice reeds.  This reed sounder is my fan powered unit which I have recently made.  Now for practice filing.

[Parker135]

I'm curious to know what kind of fan and whether you measure the pressure in any way.  

[David Lay]

8 hours ago, Parker135 said:

I'm curious to know what kind of fan and whether you measure the pressure in any way.  

I do not have a way to measure the pressure nor do I have data on what pressure is appropriate.  However, the fan has variable speed control and I installed a vent and damper in case the fan was too powerful at its minimum.  With these controls, I can vary the pressure over a large range.  The damper is the aluminum slider on the side and it covers a vent that is nearly the size of the fan exhaust.  I could easily connect a manometer to the fan chamber, I suppose.  If you know a source for pressure data, please share it.

Edited January 29 by David Lay

[Don Taylor]

David:

 

Is that fan quiet enough to be on your workbench while you are tuning?

 

I built a tuning rig using an old hand-held vacuum cleaner but it was so loud that I had to rig it up with hoses and run it two rooms away from my bench.  Not very convenient.

 

Added later: Looking at your first picture again I guess that the fan is actually inside your tuning rig, if so then that answers my question.  Looks like a really convenient little rig.

 

Edited January 29 by Don Taylor
Added further comment about your box.

[David Lay]

2 minutes ago, Don Taylor said:

David:

 

Is that fan quiet enough to be on your workbench while you are tuning?

 

I built a tuning rig using an old hand-held vacuum cleaner but it was so loud that I had to rig it up with hoses and run it two rooms away from my bench.  Not very convenient.

 

Very quiet.  The sound you hear is the reed.

[Don Taylor]

Can you run that fan in suck mode rather than blow?  

 

Added: Ahh, Mea Culpa, looking again I see that the outlet for blowing air is against the vent and damper at the side of your box so that the fan blades will suck air down through the reeds into the box.

 

 

Edited January 29 by Don Taylor
Added realization about how air is sucked through the reeds.

[David Lay]

1 hour ago, Don Taylor said:

Can you run that fan in suck mode rather than blow?  

 

Added: Ahh, Mea Culpa, looking again I see that the outlet for blowing air is against the vent and damper at the side of your box so that the fan blades will suck air down through the reeds into the box.

 

 

The fan only exhausts the box, and the accordion/hybrid reed is turned over as needed.  I made the reed holder for 16mm wide hybrid reeds which seems good for my needs at this time.  I had the thought that I could have made it with more than one step in the holder for larger reeds.

[Don Taylor]

Is the exhaust for the fan at back of the box or is it at the side where you have a metal adjustable damper?

[David Lay]

Exhaust at the back.  In this sketch, there is a neoprene gasket under the top.

[Cathasach]

This inspired me to start my own tuning bellows.

Photos are too big for concertina.net: https://www.instagram.com/p/DFmPmcxRgX1/?igsh=MzRlODBiNWFlZA==

 

[Duncan Luddite]

On 1/28/2025 at 12:57 AM, VIN said:

Apologies for what is I’m sure an old chestnut of a question, does anyone have a set of old bellows that could be used in the making of a tuning bench that I might buy, il happily pay the postage obviously, many thanks, vin

G'day Vin, Sorry I didn't get to the conversation earlier, but here's what I did.

    I found an accordion bellows pattern (a search of 'diy accordion bellows pattern' should get you some results to work with) and made one out of paper (with the join halfway along one side, not near a corner), which I stuck to a couple of pieces of plywood, the top one being longer so that a light screw clamp can be put over it to attach it to my work bench. Several holes were drilled through the top ply to make the intake/reed air port (ignore the over large central part of the hole. That was a mistake), and the exhaust ports, which have soft leather flap valves.
   The whole apparatus compacts right down and will slip into a bookcase. I use an elastic hair tie to keep the bellows closed when not in use.
    A 'mounting plate' was made out of more ply for mounting the reeds to, the underside being lined with suede, dressed with Vaseline to help it stick in place/seal, and a card location frame put on the top bellows ply to give a consistent register. Make sure you don't cut the air slot for the reeds too long, as the slot will start to creep out the end of the smaller reeds, giving a bad seal; or make two or three mounting plates with different sized air slots to comfortably cover all reed sizes. A leather flap valve is fitted under the air slot.
    To hold the reeds in place I use two strips cut from a hardwood Venetian blind that have been sanded to a bevel along the inner edge (to match the bevel on the reed shoes) and sanded down in thickness to match the height of the reed shoe, and are held in place by 4 'Button head' screws, one at each end. Slightly slackening them allows the strips to be pressed against the edges of the reed shoes, at which point they are re-tightened.

    Geoff Wooff pointed out that the reeds, while in the concertina, will play at a slightly different pitch than when they're in the tuning bench, so you need to find out their value in situ, then find their value on the tuner bench so you don't over shoot your target.
   Photos of what I was describing are below.
All the best with the project.

Edited February 5 by Duncan Luddite

[Alex West]

Alternatively, if you want a set of concertina bellows to make a tuning jig with, I have a spare set you could have (might need a little patching work but should be OK for the intended purpose

[Duncan Luddite]

@Alex West, Those are gorgeous bellows

[Alex West]

19 hours ago, Duncan Luddite said:

Those are gorgeous bellows

Scrapped and repaired Jeffries bellows with new papers

Alex West