Jonathan/Date: 20 Jul 12 - 02:46 PM
".. increasing the diameter of the buttons on an English is a really bad idea. It makes them much easier to hit".

RE:?? I guess you mean that an increased diameter with preserved c-c distance between buttons makes *adjacent* buttons "easier to hit"(?).
Well - all buttons are easier to hit if wider, but jamming IS a potential drawback with wider ones. With the trad English keyboard measures maybe 6mm diam is a limit with key travel up to 4mm. I have put 6mm buttons on instruments for players with rather chubby fingers and they were satisfied still.With increased c-c distance and/or less key travel - compare computer keyboards - you get a completely different situation.

"Increasing the size of the keyboard to compensate is also a bad idea, since it makes some of the buttons more difficult to reach, especially for people with smaller hands and/or shorter fingers".

RE:For the English the transversal measures may be increased up to the standard for Anglo/Duet without any negative effects at all in that respect.The trad c-c measure 12,3mm is a complete mystery since it may only suit a child.
The longitudinal c-c measure naturally may become a problem if increased but this in turn may be taken care of ( within limits of course) by using more functional handles.

Again we have to face some general conditions regarding the concertina concept itself.Pick the common 48 key treble English when used for single note folk tunes.Skip 8 keys at the top and 40 keys would be sufficient for all.32 keys probably for more than 90% of the tunes.A 32 key English with the trad size can be made with a lot better general ergonomy than the 1844 patent illustrates.

There is no need to compare with Chemnitzers or Bandoneons concerning general size.With common accordion construction they can be made smaller than they usually are, while British style concertinas with accordion reeds tend to become bigger than the trad models...