Crabb 12 Button: How To Remove Reed Pan?

[william galvin]

I recently purchased a mini (12 button) Crabb concertina from my partner. [We did a comic juggling show - with a little music - "Hot and Neon" for about 20 years, mostly in theaters in Europe. He bought the concertina in London in the early '80's.] One of the 2 reeds on one button has gone quite flat. I bought the concertina repair book but could not figure out how to remove the final plate to reach the reeds. However, there is a picture in the book of a mini with the plate removed. Is the plate glued or is it a friction fit? I was afraid to pry it open and perhaps damage the seal of the bellows. Also, there is a small screw in the plate - I could not understand its function. If you have any information about this or know whom I can ask, it would be greatly appreciated.

 

Also, I wonder what the value of the mini Crabb concertina might be?

 

A final puzzle for me is why all references I have seen suggest that non-professionals should not attempt to tune a reed. Perhaps ignorance is bliss, but I had planned to carefully file a bit off the middle or the end of the reed depending on which way the tuning needed to go. I have done this with harmonica reeds which would seem to be more delicate. I have 3 concertinas: 12 button, 32 button and 54 button so tuning is probably unavoidable sooner or later, although this will be my first attempt.

 

Thanks for any thoughts.

[Geoffrey Crabb]

Hi William,

 

The reed pans or plates as you describe them are held in by friction. By gripping the small screw in the corner of the pan with a pair of square nosed pliers and gripping around the end bellows frame in which the pan is fitted with the other hand it should be possible to pull the reed pan straight out. Do make sure that you note the orientation of the pan for correct replacement.

From your description I would suggest that the affected reed tongue has cracked, this is quite common with miniatures used professionally. If this is the case then replacement of the fractured reed tongue will be required.

Although I was involved in the making of this instrument, I have not been actively involved in the trade for many years now and am unable to undertake repairs or to offer valuations at this time but I am sure you will find a repairer to satisfy your needs within this site.

Perhaps you could let me have the instrument number and I will confirm the manufacture date.

 

Geoff Crabb.

[d.elliott]

The picture in the book is one I took of my own instrument, a Wheatstone 12 key miniature, and its exactly as Geoff describes. The screw is in place as a substitute for a thumb hole, as a means of gripping and pulling the reed pan. Be warned, the chamber walls will be very delicate.

 

The reed tongue replacement will need a high level of craftsmanship, I have replaced the tongue on the higest B of an English treble simply by measuring the thickness of the reed stock used, this means measuring the old reed where it was clamped. Then selecting an old feeler gauge of the same thickness, tempering it back to dark straw, then cutting and fitting the new tongue from that. Feelers are hardened highish carbon steel, not dissimilar to clock spring steel. They are relatively cheep and easy to get hold of.

 

I then measured the thickness of the old reed in a couple of places along its length and rough filed the new reed to about 0.010 oversize, fitted it and tuned it. I have found that its important to get to the same basic thicknesses as the old reed or the response characteristics/ speaking volume are affected.

 

As to tuning yourself, thats fine as long as you have an accurate standard or meter to work to, you have the tools and craft skills, and are prepared to take the responsibility for what you are doing to a valuable instrument. I don't say that people should not do these things, only that they should go into the job with their eyes wide open, and prepared.

 

Dave

[Pete Dickey]

Hi Dave

 

Just wondering about sources of spring steel. Have you also considered the return spring in a tape measure? Is it too thin?

 

Pete

[d.elliott]

Pete,

 

If you examine the reeds of your concertina, looking at what you can see that sticks out from the back of the clamp, you will see that there are several different starting stock thicknesses. I don't know if they were all ground out of a single common stock, Geoff C wrote an short article on reed manufacture, that might tell us. However for the lone craftsman/ repairer who might have a reed tongue to replace every year or two I share my experience. A quick peek at some spare reeds shows a variation around 0.2; 0.5; & 0.8 mm.

 

No doubt that you could take the spring from a broken steel tape, it might fit one of the groups of reed tongue stock sizes, just avoid anything magnetic!

 

Dave

[Geoffrey Crabb]

Although slightly away from Williams question. The following may help or be of interest to others.

 

As Crabb reed tongues were never ground but hand filed it was more economical both in labour and file cost, to remove as little metal as possible when voicing or profiling steel tongues. Depending on the frequency of a note and any special requirements, an appropriate thickness of tongue stock was selected. It may be appreciated that with a long running workshop, measurements tended to be ignored as experience indicated what starting thickness was required. Tongue material was generally referred to as thin, medium, thick and very thick. This is obviously no good to those seeking dimensions, so I have measured the stock that was used. Here are some measurements and suggestions for where used in Crabb ‘English’ Concertinas. For Anglo and Duet instruments some compromise may have had to be made depending on what internal space was available, in general though the reed tongue thickness would be similar for all notes with the same frequency within a given range no matter what type of concertina. Being somewhat old fashioned, I hope the metric conversions are correct.

 

Remember that these are the thicknesses before any filing was commenced.

 

Thin - .016 inch. (.46mm)

(C0 upwards). All Miniature & Piccolo reeds, all Treble English 48,56 & 64K

Medium - .022 inch (.56 mm)

(C-1 to C0). The lower reeds of Tenor English 48K & Tenor-Treble English 56 & 64K.

Thick - .030 inch (.76 mm)

(C-2 to C-1). The lower reeds of Baritone English 48, Baritone-Tenor English 56 and Baritone -Trebles 64 & 68K.

Very Thick- .035 inch (.89mm)

(C-2 downwards). Used on all notes below the Baritone Range. Because of the accommodation limits within the external size of some low range instruments (Bass & Double Bass) many reeds were loaded at the tips to attain the required frequencies.

Note C0 = Mid C

 

The measurements given above may prove helpful as a starter in selecting samples of reed steel but in no way should they be considered definitive.

 

Advice on suitable alternative sources or adaptation of spring steel is very difficult for me having had the benefit of access to the material bought for purpose. Only experimentation and practice with perhaps one or two suggested pointers can yield answers to often sought questions.

 

Geoff Crabb

[william galvin]

I am surprised by and grateful for the immediate and thorough replies. The number stamped on the decorative metal plate is 18642.

[Geoffrey Crabb]

William,

 

The records show that 18642 was made in December 1985 and is described as a 12 Key Mini in G. Buyer - Mock.

 

I can say that the woodwork, action and endplates were made by myself and the reeds and bellows by my brother Neville.

 

I hope that is of some use.

 

Geoff Crabb.