Hello Guys! For some funny intuitive reason I looked in at Mudcat for the first time in more than a year and found this old thread been awakened so I just have to say a few words!

Richard, of course bad endplate bushings are a nuisance causing rattle but as you certainly know to get a safe cure of the problem all parts have to be fit. That means: good endplate bushings, good button hole bushings and washers, correct tolerance between guiding pin and action board holes,no friction or hooking between lever and post AND suitable materials! I have noticed for example that all metal buttons make more noise in general than wood, bone or plastic buttons. This being one of the causes of the often misunderstood "noisy" action of Lachenals vs Wheatstone instruments.
The trad action construction of concertinas might be a lot improved by several means. It seems as if most makers have looked for some kind of compromise between acceptable quality and simple processing and assembly. Not surprising in any way.
I use 6mm diam buttons on all my instruments but this is a compromise also due to general keyboard measures. If possible I would prefer 10-13mm diam

Steve, Very pleased to hear about your interest in experimentation.I would certainly like demonstrating my modifications if some suitable occasion comes up. Concerning weight...despite my general approach tnat ´"concertina weight mostly does not matter" I admit of course that it certainly may matter unless you handle the issue in a constructive way! IF you DO - by using efficient handles and some individually proper way supporting the instrument particularly when playing standing - then the weight "problem" should be eliminated.