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d.elliott

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Posts posted by d.elliott

  1. On 9/28/2021 at 9:36 AM, SteveS said:

    I'm surprised Barleycorn didn't know the maker.  Rock Chidley concertinas have one typical diagnostic - there's a bird's eye cut into the fretwork on each side - look below the little finger rests.

    Yes I use the same tell-tale  of the birds head, beak and eye, although I don't know when they first started using it, or even why.

  2. 5 hours ago, Dana Johnson said:

    The stiffness of an alloy is defined by its modulus of elasticity, sometimes referred to as Young’s modulus which measures the amount of strain produced by a given stress, where strain is a measure of elongation under stress.  This is not the same as tensile strength or yield point which refer to the amount of stress needed to produce permanent change.  While tensile strength and yield point increase with increasing hardening of an alloy either by heat treatment in carbon steel or work hardening in brass or other nonferrous alloys, only one number is listed for the alloy’s modulus of elasticity.   I once tried hardening a reed of 1095 steel to a temper starting at file hard, where a file would not touch it, and gradually lowering the temper to light blue where it was quite soft, but not really annealed.  This didn’t change the pitch (which depends on stiffness) but had a large effect on how easily the reed was to permanently bend or change the set.  
       A long time ago I switched from 1095 steel to the Uddeholm  UHB-20C alloy which has as one of its listed uses as accordion reeds and is produced in a somewhat harder temper than the blue tempered 1095 steel.  This alloy seems slightly stiffer, and I found that a given profile will have a higher pitch.  It also  shears cleaner and holds its set better which I like a lot.  
       We normally equate stiffness with hardness but I think that is because most of the stiff things we encounter are also hard.  Brass of any hardness is less stiff than any steel.  I have a hard time letting go of this myself but  if you want to calculate the frequency or amplitude of a reed, the number you use is the modulus of elasticity.  If you want to calculate the amount the reed has to bend before it won’t return to its original position, you use the  tensile strength yield point.

         Dave’s remarks about detempering a reed with hot solder are still an issue, though since it only is used at the reed tip where the steel is at its greatest movement but least bending, done properly,  it doesn’t  influence the part of the reed where it would cause real bending trouble.    Regardless, doing no damage to a reed is the goal.  especially on old and valuable instruments.  You need to avoid heating the reed except where the solder touches it and removing the iron as soon as you see the solder wet the steel.  The flux works at the low end of the temperature, and the melting of the solder helps absorb the excess heat that might overheat the steel.  I use a Kester brand low temperature silver bearing lead free solder that melts at about 215 degrees C, with a synthetic rosin core (removable with alcohol and non-corrosive residue  ) that leaves the underside of the tip at a light straw.  It wets the steel very well and stays bright for many years.   
        Please pardon my inability to keep things brief.  For me, this is talking shop, so I get carried away.

    Best wishes to all,

    Dana

     

     

    Dana,

     

    I like talking Shop, a bit, The original poster talked about applying something along the spine, that would be root, belly and tip (you see I am picking up your terminology). Hence so much concern about destroying the temper around the working part of the reed. When soldering at the tip I always use a clip on heat sink to protect the elasticity of the reed tongue. For a 18 months I worked as Manager of a mechanical & metallurgical test house proving the properties of aerospace & down hole materials, I want to relapse into tech speak, but I guess most of the readers just need to know that soldering, other than at the tip can be harmful to your reed's heath, and then even at the reed tip to use heat sink protection and low temperature solders where ever possible.

  3. On 9/17/2021 at 1:03 PM, David Barnert said:

     

    Is there any general agreement on which is the right-hand spring and which is the left? I have always assumed that the right-hand spring is the one with the hook that curls around the lever like the fingers of the right hand and vice-versa, but I’ve never actually seen that in print. Page 25 of your book talks around it without actually making it clear, but suggests the other convention, saying that they “usually hook to the left” (which is what I would have called a right-hand spring), but does not explicitly say that this is a left-hand spring. For having a few spares, it’s easy enough to just order a few of each, but for replacing a whole collection with many that hook left and few that hook right it’s important that the buyer and the supplier are speaking the same language.

     

    I have always wondered if my assumption about this is correct, Looking from the pivot post he LH spring has the pig-tail wound the the LH side of the anchor spike, and has the hook bending the the left of of the pigtail, The RH spring has it's pigtail wound on the other side of the anchor spike  with its hook bent to the right of the pigtail. I am probably wrong

  4. Thanks Dana, I had to read this several times to take it all in. I need to be more explicit and refer to the root rather than the belly of the read when talking about pitch reduction, I had not realised that this could be misleading. Whilst I have known for some time that there is neutral zone where attempted adjustments in pitch yield little or no result, I have never thought of this being an area to reduce reed stiffness. Information for which I thank you. 

     

    Obviously one of the factors in reed stiffness is the grade of steel used for the tongue, it's composition and and it's metallographic condition. I am not a manufacturer so I deal with old reeds made out of high(ish) carbon clock spring steel. My own Aeola has reeds tempered to straw, many, if not most instruments have reeds temped to blue. This range of tempers is achieved between 220 deg C and say 300 deg C. I mention this to caution those who feel that they can add solder near the working part of the reed tongue's length. solders come in various alloys with melting points between 90 and 400 deg C plus. the majority of general solders are around 300 deg C. the reed steel must be at least the melting point of the solder for 'sticktion' to take place. It is easy to affect the temper of the working area of the reed, softening it, increasing it's ductility and reducing the stiffness or springiness to the reed. This will adversely affect the reed performance.

  5. Its about the ratio of the tip section and the strength of the belly of the reed, if you file the belly of the reed leaving the tip un touched the the belly is weaker and the pitch drops, The term is flexural rigidity. I guess you are talking about reinforcing the reed belly, it's working area some how. what ever you use would have to be in its self springy, at the same level as the reed steel and work homogeneously with the reed. 

    • Like 2
  6. Use a spike to form the pilot for a new hole adjacent to the old spring anchorage point no harm will be done and you will be up and running again. That is what a professional would do. Short of digging out the old spring end, drilling or chiselling a cavity in the action plate, gluing in a bit of new wood, then dressing it flat before fitting your new spring, it is all that can be done. You often come across evidence of spring replacement with old spring holes and stubs left in them. It is no detriment, just a small footprint in the history of the concertina.

     

    A 'get you away' remedy whilst waiting to replace a spring is a small piece of kitchen sponge pushed between the pivot post and the key, cut thick enough to hold the lever arm up and thus the pad in place.

    • Like 1
  7. I did not read it like that, never the less I shudder at the thought of soldering tips of reeds to reduce the pitch by half a semi-tone. Button Box have a good reputation, I don't know Mr. Snope, but in 30 + years I have only seen this technique applied in the manner suggested, once. When the reeds were nickel silver and too delicate to risk thinning the read tongue bodies to flatten them.

  8. 13 hours ago, Everett said:

    Here is what an overhaul of a vintage instrument can look like

     

     

    The concertina is a model 21, 48-key treble, manufactured in London by Wheatstone in 1927. It has flat metal ends, metal buttons, and a newer 6-fold bellows. Most of the parts, besides the bellows and thumb straps, appear to be original. The concertina is in "old pitch", and is approximately 55 cents sharp of A440. There are numerous, small cracks in both pad pans, which have been "finished" by a previous repairperson, possibly in an attempt to fill these cracks.

    Recommendations:

    1) Fill the pad pan cracks with glue to eliminate air leaks. This will involve removing and replacing approximately 12 pads.
    2) Replace the valves.
    3) Replace the thumb straps. This is, perhaps, optional if you don't find them objectionable; I find them uncomfortably stiff.
    4) Shim the bellows frame gaskets to eliminate leaks between the reed chambers.
    5) Shim the reeds as necessary to fit snugly in the reed pan.
    6) Add solder to the tips of the reeds to bring the pitch down and tune to A440. I believe we discussed this on the phone. It is more time consuming to tune this way, but it eliminates the risk of damaging the reeds by over-filing.

     

     

    I have to say Everett, that your experience of this instrument is unfortunate in some ways, but pretty typical in others.

     

    taking your points:

     

    1. this cracking occurs (in my experience on less than 5% instruments, then only say 4 pad holes on an instrument). the big cracks along the grain usually need opening out and a filler of veneer applying. Often just running glue into small cracks will be enough to stabilize them and seal any air paths

    1.1 pads usually need changing because they are knackered, and you change the full set together, make sure you have a supply of grommets

    1.2 springs as needed?

    1.4 repair shrinkage and glue failure around the pad board/ casing rebate (say 40% of instruments) I would check this before padding.

    2. agreed replace all valves

    3. agreed, thumb straps are a conditionally based task

    4. leakage here is quite rare,  usually a roughening up of the chamois leather knap is usually all it needs

    4.1 more often, ensure all reed-pan support blocks are present and fully secure, shim the top surface of the support blocks to ensure that the chamber wall gaskets are in contact with the underside of the pad board when the instrument is closed up

    5. Agreed, reed assemblies have to be secure but don't over-do it, you don't want to cause reed tongue/ frame pinching

    6. You shocked me with this one????? The least risk to the reed is to drop the pitch by filing with a 400grit diamond file , usually you are only looking at half a semitone, worst case just over a semitone (the case here). If you are using solder, apply a heat sink and use a very low melting point solder, soldering reed tips is usually an act of desperation. also check the underside of the reed tongues for corrosion and any accumulation of dirt, scrape off. Check also the reed frame vent's inner flanks for any accumulation of Verdigris that may foul the reed tongue. 

     

    You should also expect to have some cross bushings to replace, maybe some dampers, and then action box endplate bushes (all at once) if necessary. This may require the removal of the bushing boards.

    Critically any structural long woodscrews through the thumb strap and finger slides must be present and secure. Ensure the structural pillar-spacers that the long screws pass through are in place and if needs be replace the card packers on top of the pillars.

     

    I hope that this helps.

     

     

     

  9. From time to time I have experienced the this sort of problem on various instruments, I have never truly understood the issue but I have found that the following has helped. running a 400 frit file round the frame vent and across the top surface of the frame to ensure a clean edge around the reed vent, and the removal of any burr, then polishing the flanks, and tip of the reed tongue to ensure no burr or accumulation of dirt or even corrosion. Then re-centralising the tongue in the vent.

     

    I can recall changing the reed tongue in one instance because the reed had been filed in such a way that the filed surface was far from parallel to the under side and that the filing seemed to be closer the tip than I would have expected. This did work, emphatically!.

     

    I suspected that the reed was beating with a figure of eight path, and that there was possibly a slight secondary flex to the reed. I am talking an old and traditional reed here.

  10. most likely a spring, there are two types, Left hand and Right hand when ordering get one of each to avoid disappointment. It is possible to turn a spring from one hand to another, but the hook end can break off. Try to avoid steel spring replacements, they can be a bit too strong. You are better with brass or phos-bronze replacements.

  11. 20 hours ago, Wolf Molkentin said:

     

    Thank you Steve, your post is paving my way to pointing out that the "model 8" as advertised by The Button Box does actually not appear to be one - at least not a typical example, as it would have raised ends then (just like the one I own myself).

     

    All the best - 🐺

     

     

    The Button box description is correct. This is a no 8 if you look at the light patterns in the polish it is clearly a 56k raised ebony ended instrument is a model number 8.

     

     

  12. I can usually count on two or three instruments a year that are fitted with spruce baffles, some odd ones with heavier leather baffles. They do suppress volume, and tune out some of the higher harmonics making the tone more mellow. Equally there seem to be a number of 'German Silver' reeded concertinas surfacing at the moment. This an alloy of copper, zinc and nickel, (no silver). Some times called nickel -silver , it is a brass with around 18%, less copper, and but with an addition of around 25% nickel, the rest being zinc. 

     

    The most interesting use of baffles that I have come across has been where a horse shoe shaped baffle has been fitted to mask the power of the lower notes on the big reeded bass concertinas.

  13. As a matter of interest. I decided to find out more about the Accordion-Concertina Repair and Technician's School. I struck me as a good idea to have an institution nurturing free reed technical skills and giving some form of formal qualification. The qualification is a 'certification diploma', a term I am not familiar with.

     

    The Accordion-Concertina Repair and Technician's School. publishes a comprehensive and excellent curriculum relating to accordions etc. but I did note that concertina modules relate to, and I quote 'modern versions'  for both English and Anglo concertinas. So I think it safe to infer that traditional 'vintage' concertinas are not currently within their scope. Hopefully a future development for them? Especially as there are manufacturers producing high grade reproduction instruments that use the concertina reed design.

  14. On 8/23/2021 at 12:45 PM, John Wild said:

    I suspect removing the reeds only would not make much difference to the weight. You would still have a larger instrument in its larger frame. There is the question of the overall size needed to accommodate extra reeds/reed chambers.

    Actually John, it does make a difference to weight, think of all the brass in the reed frames that you would be setting aside, yes the reed frames are slotted but I recon that 48 reeds with an average weight of 25 grams, 1.2Kg..

  15. On 8/22/2021 at 8:23 AM, Richard Mellish said:

    Bass Englishes are usually single action, but why do you need that?

     

    1. Weight, big reeds are heavy

    2. double action big reed instruments need big valves, which (no matter how skilfully set up) are slow to respond and can cause breathiness and delays in note sounding

    3.  there is more room in the instrument to enable better balanced reeds which have a better tone, more power and responsiveness

    4. more room in the concertina for a better compass, especially on 'G' basses

    5. cheaper to make.

    6 less effort to play, less tiring on the wrists and thumbs.

     

    and so on.

  16. When I posed the question about tuning technique it was not to denigrate the capability and experience of the repairer in Wisconsin, but to caution people in general that the traditional, vintage, English made concertina reeds are a different proposition to the accordion reeds, and indeed accordion derivative reeded instruments. I am working on a 1906 Wheatstone 56 k extended treble fitted with single rivet retained reed assemblies. This shows every evidence of having seen a scraper, and possibly a Dremel tool. two of the very top reeds are ruined, and irreplaceable. The skill evidenced by the previous tuner in the use of his tools is very good, alas not so his/her concertina experience, nor their understanding of tuning tolerances in such an instrument.  an over range of +/- 12 cents does not cut the mustard. 

     

    When electing to re-tune I think the motive is important. 

    • Are we wanting to play with other musicians in sessions, or bands, if so A=440hz as a nominal standard is expected., less important might be that the instrument is overall a couple of cents sharp or flat. If you are wanting to play concertina band then the deviation from nominal becomes more important.
    • Is it because the instrument is not in-tune with it's self? octaves are wrong or the notes are not consistent between push and pull (English/ Duets). If you are playing solo  and or/ for singing, the nominal pitch is immaterial. I would suggest that some reed adjustments rather than re-pitching the concertina is a reasonable course of action.
    • Perhaps you feel that the concertina will become more valuable, or certainly more marketable if tuned to concert pitch. The concertina will certainly appeal to more people and be more versatile.

    I council my customers along these lines, once an instrument is re-pitched it is very much down a one way street. 

     

    There is something about melodion pitch, I think it involves so may paces and a skip, but I might be biased.

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