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Chris Ghent

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About Chris Ghent

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    Heavyweight Boxer

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    Blue Mountains NSW

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  1. These are the deeds of repairers. There is nothing intrinsically wrong with using different leather on the partitions, what matters is that is seals. And while I wouldn't do it, I have seen many instruments with a screw through a reedpan block. It works but seems unnecessary when glue would work on its own. If at some time later you wanted to move the block only a small amount the screw would no longer work though you could plug the hole and drill again. The one you picture is unfortunately placed: the screw, which is essentially a wedge, is being forced into a join between two pieces of wood. It has to be weaker than before the screw went in.
  2. Chris Ghent

    Perfecting a setup

    It's south, we also suffer from the sense the northern hemisphere is somehow the top of the world and that anything that falls can be seen to be slipping downwards towards the south pole. If anyone goes down there to through the giant piles of things that went south I'm looking for a sock, made from possum fur, black with a blue heel. The possum is probably looking for it too.
  3. Chris Ghent

    setting the reeds for nice attack?

    Wolf, I noticed your statement in the other thread and it does not tally with my experience. When the reed set is very high you will get a bit more cut but the effect on the output at low pressure is not quiet playing, it is no noise at all, just a sound of air passing the reed until sufficient pressure is attained so as to start the reed. This sometimes feels like a delay in starting at low pressure. If your reeds will play quietly and you have a bit of cut at volume then it sounds to me as if they are adjusted very well. The equation goes something like this; when the reed set is low the reed starts easily and has a slightly more mellow sound. It is however prone to stalling or choking if the initial bellows pressure is sudden and high. When the reed set is high there will be a little more cut in the tone but the reed will not start well without a lot of pressure and it is difficult to play quietly and have control over note starts. Somewhere in between these two stations lies a way which will suit our individual needs, for example, an Irish dance player might want a little higher set than a person who wanted only to play airs.
  4. Chris Ghent

    Perfecting a setup

    If the sluggish reeds were not like that after the Dipper rebuild then the most likely culprits would be valves (not just the ones that won't close but those that won't open) or leaks from either shrunken or warped wood or from reedpan blocks no longer being in the best position. The reeds could also be inefficient due to too great a clearance or the set could be too low. Try one of the sluggish reeds by putting sudden immense presure on the bellows and see if the sluggishness is worse, a sure sign of low set. Check where the pads for the sluggish notes are located, they may seem random on the keyboard but be near each other on the pan. If so check the pan blocks and the sealing between the pan and bellows and how flat the reed pan is. Check all of these things anyway. Check the partition gaskets don't stop short of the bellows frame walls in those chambers. HTH
  5. Chris Ghent

    Buzzing Reed

    Could be the valve next to it. To test, change the valve, remove it, or put a tiny piece of sellotape to hold it down. If the buzz goes away then change the valve. Another clue as to whether it is the valve next to the reed is if it is worse when you change bellows direction without lifting your finger off the button.
  6. Chris Ghent

    making a jig for springs

    You can make more than adequate springs on a very simple jig, all you need is a four inch nail, a brad, and a piece of round wooden rod. Drive the four inch into the end of the wood and cut it off at about 4mm. Put the brad in 15mm away and cut it off at 2mm. To use, put the bend into the wire for the foot, hook it around the brad, make three turns around the four inch holding the wire low as possible to keep the coil tight, and stop bending when the top run is at at or near the required angle for the preload. Cut the wire a little long. Form the hook directly above the foot and cut off the excess. Correct the foot and hook angles. If you want to make it look flash you can bend the top run over sideways as it comes off the coil and then reverse that bend a little further out so top and bottom runs are in the same vertical plane. Sorry about the mix of imperial and metric, a four inch nail is a colloquial term here, they used to be 4 inches long and 1/8" in width so about 3.25mm in width.
  7. Chris Ghent

    Harsh Reed Work Around

    It seems strange that the only reed different to the rest should be harsher when it is more usual the other way around. Can I suggest shifting the reed to a different position and seeing whether the harshness follows it? If it does then it is either touching, has much tighter clearances than its peers, or is ridiculously thin. As an easy fix it might be the best thing ask around for a replacement reed of the same value. If the problem vanishes when the reed is shifted then it may be the wood slot it is in is shaped to jam one end of the frame but not the other. If the problem stays in the original position then it may be again one end only jamming. This can easily happen when a person reshapes a frame to fit a different instrument and it sounds as if this is true of all of the reeds in your concertina. When a mishapened frame jams only at one end it is often hard to see. Putting a thin sliver of paper down between the frame and wood roughly alongside the tip of the reed while you put the frame in is helpful; if it is easy to pull out when the reed is in then it is too loose at the tip.
  8. Bill, thanks for the insight, I have seen them on eBay and wondered how good they are. I'd like to have one, I can think of a lot of uses for it, but always suspected 40 watts would not be enough. It is hard to know how much power would satisfy me in terms of quality.
  9. That is what I have always done but the laser would not even have to think about it, what would it add, 30 seconds to the process? What sort of power does a laser need to whack through 3/16" ply? Does it do it in one pass? If I could use that site for the drawings and find someone to do this locally I would probably return to wooden cases.
  10. I'm impressed, was making it with the lid ready detached a possibility..? I second the suggestion of birch plywood...
  11. Chris Ghent

    Stiff Bellows

    When people say the bellows seem stiff it can be that the instrument itself can only easily be played quietly and slowly because the reeds are not efficient. I think in this circumstance the best approach is to play quietly and slowly and when you are ready, spend more and get a concertina that is easier to play. If it is actually the bellows then you can test this by holding down as many buttons as possible (or the air button if you have one) and working the bellows in and out to gauge how much effort is going into them.
  12. I have a 1/5 comma meantone anglo centred on G. I find no-one notice the pitch differences in my regular sessions but I am always a little reluctant to give an A for tuning when asked because it is 4 cents out. The concertina is not just sweeter in chords, it seems when playing melody your mind adds up the intervals on the fly and the notes seem sweeter. Having said all that, I would not go out of my way to tune to 1/5th again as the gain is a little too small even though there is no real pain. If I was sure I would be playing on my own for a long time I would shift to 1/4 without a pause.
  13. Chris Ghent

    Suggestion For Experiment

    Tom, Thanks for the gentle history lesson, I followed the links back to the previous conversations, which I had forgotten, and I can see I owe you an apology for throwing un-thought out and unattributed contributions into the current topic. Going back reading those discussions was to return to an old country with fewer shadows and one in which I seem to be a better thinker! A lot has happened since then. Let me talk as one who in a lab might be called a reed technician. If your intention is to throw light on whether brass reeds sound different to steel ones then I am happy in this instance to do the technical work for you, up to a point, which is to say, if it is not too time consuming. Making a steel reeded assembly is not at all time consuming, one with a brass reed is a little time consuming, mainly in the developing of new skills. So that I can do. I will still have technical clarification questions; the two areas which come to mind have already been touched upon, clearances and brass hardening. Sadly, there are two things I cannot understand. One is the concepts you express as equations. In another lifetime perhaps. The other is the technical terms you use ie. " Mathematically, it is called a non-dissipative (frictionless), homogeneous formulation, and the utility of it is that it (along with its boundary conditions) provides the eigenfunctions for any type of bar vibration consistent with its underlying simplifications..." and etc for the rest of the paragraph. I have no doubt I could get there eventually on that sentence but I have not the will nor the time. So in order for us to get to what you want I will need you to be very prescriptive in simple terms. The aim, the projected method, how it will be tested. So far I have the initial aim as, to test whether the two sample reeds, steel and brass, will vibrate the same way. The method is; to make two reed assemblies, one with a steel reed, the other with brass, both with the same bar profile, width and length. The brass one to be 1.41 as thick as the steel. Evaluation methods yet to be discussed. Later we will look at timbre. How am I going?
  14. Chris Ghent

    Suggestion For Experiment

    Hello Tom and Johann I could do this but not until at least June. I have never seen/heard what I would call a quality brass reed ie. one with excellent clearance between reed and frame. Consequently when people say brass reeds sound different to steel I wonder if it is a quality difference we are hearing more than or as much as an intrinsic material difference. This is similar to the argument "later Wheatstones are not as good as early ones. Later Wheatstones have aluminium reed frames. Aluminium frames are not as good". So while the test would need to be simple in order to get done can I suggest the clearance between tongue and frame would need to be consistent across both examples? If brass reeds were to create a different and warmer sound than steel then it will be for a specific scientific reason, not because they are honey coloured. My guess is they would have a different stiffness and for this reason it would be interesting to be able to measure the tip speed of the reeds. This might not need fancy equipment, maximum tip height above the frame could be used in conjunction with hertz to calculate a speed. This would mean we could see if any difference in higher partials and consequent tone might be explained by tip speed. The time involved to create the steel reed assembly would not be great, but sourcing brass at the right hardness would be an issue, starting with an ignorance of what that hardness might ideally be and even how it is measured in brass. So, a few questions ; does banging it with a hammer to work harden it only create a zone of surface hardness? What happens when you file it to create a profile, does it lose its hardness on the top? All of the brass I have here is "free machining", ie. includes a small percentage of lead. Can this be used? Does anyone have a working comparative knowledge of steel and brass profiles? Would brass and steel deliver the same pitch for the same physical profile and length and width dimensions? So many questions... An afterthought, perhaps the thing to do would be to get a brass reed assembly and copy it in steel.
  15. Chris Ghent

    Very Small Reeds

    Are the small reeds any smaller than those at the dog whistle end of a Wheatstone extended treble EC..?