d.elliott

as pads, their dots (sempers) and the leather end of arm beads (grommets) are all throw away items ,I use what Steve Dickinson advised me, white PVA glue

Would not try switching reeds about, it can result in a host of misery. There is a thought which has been expounded before, in engineering it is call burst energy. if you have a pressurised container, and you suddenly release the pressure there is a surge through the point of release, if we are talking the reverse where the container is at negative pressure the surge through the point of release is softer. It is so long ago since I had cause to look at this that I forget the details. I do remember that the HSE got quite excited about it when pressure testing pressurised railway tanker wagons. Dave

So many people seem to misread the purpose of the the long screws under the thumb strap and the finger slide. The damage that can result from omitting them, or fitting shorter screws can be catastrophic to the aged and brittle fretting. Equally, missing the spacing pillars and/ or omitting the card shims on top of the pillars can be just as destructive. I know that working out the depth of the pillar and the amount of shimming is a bit of a faff, but it is important. Dave

by wet, I mean dampen with water as per the guidance of the manufacturer the epoxy putty I use. I keep the moisture off the polish as much as possible, using a fine water colour paint brush. This does enable the putty to key into the wood grain and fragmented structure without denaturing the putty or spoiling the wood/ finish. Dave

I find that the inherent oil on the thread is release agent enough, I also wet the broken out hole in the wood to enable the epoxy to get into and reinforce the broken wood more effectively. Jake, on these lower end of the spectrum instruments, there was never an insert or plate nut fitted, the thumbscrew went directly into the wood. The screw thread was very course for this purpose.

This a common problem I use two solutions, one is to pack the hole in the action box with brown epoxy putty, insert the screw into place and ensure the screw's thread is is tightly encapsulated. set aside for 24hrs before winding the screw back out. Just clean up the extruded waste putty and the job is usually successful, and it uses the original bolts. The other solution is to use the inserts and new adjustment screws as described by others

I think Mark intends to 're-open' at the end of July, if not earlier

26 k Anglo instruments are fairly common, and they have the most used accidentals of their keying. The big question is, is the instrument in concert pitch, A=440hz, or is it around half a semitone sharp? You need to know this before tying to play with other people or learn tunes from CD's. If it is in old pitch, (1/2 semitone sharp) then it will need re-valving and probably re-tuning. I suspect that you don't have many concertina specialists, but if you can get one who is not an accordion repairer and has the right leather for the valves, and files rather than grinds reeds it would probably be best for the instrument

Valves usually make a popping sound. I wonder if it is more prevalent on the left hand side and when the bellows are being compressed, if this is the case I have a good idea what it might be.

Tom, perhaps I should have said the air pressure would decay faster requiring more effort given the larger air escapement area around a bigger reed tongue, affecting response issues, Wolf Every time you bend the reed tongue to adjust it, you are taking it through it's elastic limit, altering the stress make up across the reeds section. yes there is a risk of failure, how remote is anyone's guess. what is true is that you are probably going to flatted the reed's pitch by a few cents. If you are going down the route of profiling, then check the tuning of the reed outside the instrument fist, you may need to do a bit of gentle filing before re-assembly. Of course, filing the reed can cause the reed to distort and bend into the reed frame vent. you will then need to bend it back to profile again. If you bend the reed back to profile again then be warned this action may affect pitch again and so on an nauseam. To me, I have to ask, are you chasing a level of perfection which these reeds cannot deliver? Please just consider if harm can result? Tom, to clarify why my policy to hand work brass for reed tongue stock, you called it artisan work, (I think in the UK in Engineering circles that term is reserved for baker's of bread and the like, the highest engineering plaudit is that of 'master craftsman', in the steelworks it was a millwright, but putting that aside). You talk about the industrialised perspective. Remember that I repair and overhaul, I make enough stock for one or two reeds at a time, one to be a spare in case I screw the first up. The need can occur once or twice a year or not at all for two or three years. For me my process works. However, usually I can get a substitute brass reed assembly, if only to rob it of it's tongue and fit that tongue to the original reed frame. Dave

Wolf, What you describe about the lower end of the range is, alas, very common in softer metalled reed tongues, however to get a particular frequency there is a ratio between the 'spring' stiffness in the area of flexing, and the moment of mass of the end of the spring. The spring in this case being the reed tongue. The geometry of the reed tongue (length & width) is set by the reed frame, which is controlled by the chamber size, which is controlled by size of the reed pan, which is a function of bellows frame size. Back to the spring idea. the material 'brass' has a lower stiffness than say steel, so to get enough stiffness it has to be thicker, hence stubbier and I think, less responsive. Add to that the greater area in the clearances around the larger reed tongue, plus what ever voicing gap you optimise on and the reeds air efficiency drops comparative to a mid or upper range reed of the same material. Another factor may well be that for a constant bellows pressure the velocity of air flow will be lower the larger the reeds so it need more bellows force to compensate with the risk of stalling the reed. A steel reed in the same reed frame in the same instrument will operate differently, it will need to be thinned more to flex and will be correspondingly well, springier. What do I do? well there is only so much. I confess I have experimented with deliberately weakened (for tone) steel reed substitutes, with some success. However, I do my best to ensure the best chamber air tightness, roughing the gaskets etc. If there is a problem, I adopt the reed profile used on the big reed instruments, which I suspect focuses the area of flexing of the tongue , balancing the rate air escape along the reed flanks, I try to get away with the lowest voice gap as possible and often rely on vibration in play to optimise the gap over time. If all else fails I go back to my steel reeded instrument. Sixty years ago I was in the Wolf Cubs, part of the Boy Scout Movement, I am minded of their motto 'Do Your Best'. Dave

Hi Tom, I simply want to get as close as is sensible to the final section, I take the remnant under the reed clamp as a guide, an ensure that I get the maximum amount of work into the structure before I start filing it away. Different types of cold working have different different 'signature' crystal deformations. Rolling and drawing are not deep compression, that is most of the work is in the outer skin of the section, obviously thin section are pretty good. Forging by a GFM machine is not as good as by press, which is not as good as a hammer in terms of shocking and shattering the mid section structure. Admittedly my professional experiences were to do with ferrous alloys or super alloys, but I think that by following my path I am giving my reed the best shot of longevity. Half Hard & full hard are grade bands, I don't know the working history of what I have, and hardness seems to be as much graded by tensile yield rather than indent, but on checking annealed brass is about 90 HV; a full peak hardness at a 60% section reduction is around 183 HV, a mid range, half hard partial anneal or temper is around 110 HV. Anyway banging away with a hammer 'beats' (sorry about the pun) tedious filing any day. I may be a bit cracked, but I have not experienced the problem of cracking in the stock. Is this cold working metallurgically necessary? I cannot test it, but it is both satisfying and can do no harm, an insurance? Dave

A little bit about metallurgy, setting aside the super sophisticated super-alloys, only steels can be hardened and tempered, a process which takes carbon in and out of solution in an iron based crystal matrix. Brass is copper matrix with zinc, Bronze is copper with tin plus stuff, including phosphorus. Brass/ bronze can only be annealed by heat (softened) usually from anything around 400 C upwards subject to composition. Copper alloys cannot be hardened by heat. The only way to harden these copper alloys is by work hardening, rolling, cold drawing, cold forging. when I make brass reeds I buy rolled strip ten beat it down to section. Think of a cloth bag which has been filled with marbles (small glass balls) you can get hold of the bag, squeeze it and the balls will slide around inside, changing it's shape with little or no effort, now smash the cloth bag with a hammer shattering the marbles inside, and then try to squeeze the bag to move its contents and change it's shape. The splintered glass shapes will lock up on one another and oppose any forces applied. When metal is first melted and cast, it's crystal structure is fairly globular. it is soft and easily bent. when it is cold worked, the crystal s get all broken up and resist deformation.There is also age hardening If you are weighting reed tips to deepen their pitch you need to keep the strength in the reed 'belly' which is doing all the bending and springing work, whilst adding mass to the tip to slow the flexing down. Brass is like it's parent metal copper, extremely heat conductive a heat sink is essential otherwise the spring in the reed will become compromised. A high temperature soldering iron coupled with low melting point solder plus heat sinks to protect the working part of the reed. There is age, or precipitation hardening of copper alloys, which seems to be a factor in fatigue failures. I have also noticed that some reeds are redder than others, at first I thought of phosphor bronze, and I read that this was the case, however I doubt it, the first patents of experimental pho- bronze metals was around the 1850, commercial availability in a usable form would be much later. I think we are just seeing a stronger concentration of copper in the brass alloy, but I have no means of proving now I am retired. Dave

chest expander musician?

caterpillar driver, or caterpillar juggler??