Adjusting Button Action

[Roberta Kogut]

I am wondering what would need to be done to adjust the action of the buttons on a 1904 Wheatstone English concertina.  I feel like the buttons go down too far and I'm having trouble playing some passages up to speed.  Any thoughts?

[Theo]

Thicker pads will reduce the distance that the buttons travel.  If the pads are old it is likely that they have become compressed, which means the button rises higher when released, and consequently travels further before it stops. This is the safest fix. The alternative is to bend all the levers, but this is risky on 100 year old levers. You will need to find a good repairer who can examine the action and make pads of a suitable thickness.

Edited September 9, 2022 by Theo

[Roberta Kogut]

15 minutes ago, Theo said:

Thicker pads will reduce the distance that the buttons travel.  If the pads are old it is likely that they have become compressed, which means the button rises higher when released, and consequently travels further before it stops. This is the safest fix. The alternative is to bend all the levers, but this is risky on 100 year old levers. You will need to find a good repairer who can examine the action and make pads of a suitable thickness.

I hadn't thought about compression over the years, but that makes a lot of sense!  Thank you!

[Geoff Wooff]

A    Wheatstone of  that  period  will  probably  have  quite  thin  pads, even  without much  compression.  I  have a similar  era Wheatsone  where the  buttons  do  not  protrude  as  far  as  later  models  but  to  get  enough  travel  on those  buttons  I  have  removed  one or two  of  the  felt 'damper'  washers  from  the  locator  pins  at  the  base  of  each  button.  The  pads  now  lift  well clear  of  the  vent   holes  and  the  tone  is  very  clear  but the  buttons  do  go  down  a wee bit  further  than  I  would  like.  Whilst  the  button  height  is  quite  low  the  location pins  are almost  as  far  out  of  the  holes  as could  be  deemed  safe.  So  the  action is  caught  between  the  two  extremes  of  'buttons almost  disapear into  the ends  on  depressing'  whilst  they  cannot  rise  any  higher  on  release.  Sure the  tone is  now  a marvel  but  the  action slightly  disconcerting.

 

I  suggest,  Roberta,  adding  one  felt  washer  to  each  button  to  reduce  the   depth  of travel   but  agree  with  Theo  that  getting  hands on  advice  from  a good  repairer  might  be  invaluable.

 

I  have  adjusted the  action of  every  Engish  I  have  ever  owned, usually  to  get    my  choice  of  spring  strength ... I but  I  find these  early  models  can  need  special  attention.

Edited September 9, 2022 by Geoff Wooff

[d.elliott]

The methodology is quite simple, there are two fixed points:

 

1 when the button is fully depressed, the height of the button, fully depressed is set by the damper stack under the body of the button, the little felt rings that are pierced by the button guide peg. I have seen a stack height of anything between one to five dampers being used. The number being consistent across an instrument.

 

2 when the button is fully up, set by the contact of the pad onto the pad board.

 

The button pressed down height of button top over the finger plate is often set to be around 2.5/ 3mm this can be increased or decreased by adding or subtracting dampers.  Once this button low point is set, then the button height is set by establishing the button travel height. Button travel is usually set at 3.2mm or 1/8th inch, or there abouts. This is done by taking a measurement of the existing travel and by bending arm near the pad until you get your 3.2mm. Obviously there are a number of government health warnings that could be issued at this point. As you do the first couple of arms, check that the guide pin under the button is not likely to come out the action plate's guide hole and jam. The thicker pads simply set everything higher and given an appropriate amount of button travel there is a risk of the lever arm gromet, or the edge of a pad striking the underside of the action box cover, tapping noisily and affecting pad security.

 

I measure several button low heights (button pressed in), take an average. I add 3.2mm to the average and make a height gauge to suit. I can then set all buttons to the same height using my gauge as I bend & adjust each of the arms.  

 

I must go through 25-30 full re-pads a year so it is second nature now, but I can remember how daunting it was in my early days of repairing. If you can get some experienced to show you it is best. I always use arm bending to adjust travel, I always use consistent pads., and a consistent number of dampers per button. This gives an even key hight. Voicing is controlled by the original manufacturer's pad hole diameters. Often there are two diameters of pad hole, sometimes three diameters.