Lever adjustment

[Sprunghub]

After a little wait, I have all the necessary parts to start the pre-tune refurb of my small Lachenal Crane.  I have done half a dozen pads thus far - all is going well enough but the new pads are lifting the levers via the pivot point, on the fixing post as the new pads are thicker.  I am going to need to adjust the levers to raise the buttons and increase the pad lift when the buttons are depressed.

 

I read somewhere once that there is a right way and a wrong way - or rather a right 'place' to effect the bend ? - I think it was the lever arm at a point between the post/staple and the button ?  I have searched but can not find my way back to it......can someone confirm for me please.....  

Edited October 24, 2018 by Sprunghub

[Frank Edgley]

You have to be very careful. Bending the levers is tricky and may result in breakage.....not a good thing. How many felt rings are under your buttons? If two, you could remove one. Are the pads really too thick? as long as they raise up 1/4 inch to let the sound out, when the button is depressed, you may be alright.

[Sprunghub]

Hi Frank - Firstly, re the pads, the originals in every element, by design and time are definitely 'thinner'.  The Bristol card is marginally thinner, the felt, due to decades of compression is marginally thinner and the 'face' appears to be more akin to a chamois rather than a modern finished leather, softer, compresses more and therefore 'thinner' too.  The thickness of the black 'dot' adds to the total - the original's are ultra thin. 

Everything is 'marginal' but the marginals add up and it is that I think I need to address.  

 

Re. button felts - on the existing buttons there is generally '1' felt ring - although I have found '2' on one and they are thicker - noticeably so - than the new ones I am fitting, so I don't think they are in play.

 

Re. raise - I am not getting anything like as much 'lift' as I am with the old/original pads.  The raise/lift on a couple of the pads is almost 'nominal' and the reeds are very slow to sound now, so I am pretty sure I am not getting much (enough) air in with the available button depression.  I think it is more noticeable on the 'longer' levers......the C# and Bb are almost ok for height and pad rise.

 

I am going to add an image to try to show the difference.  The C, F, A, E, and a couple of the 'black' buttons  have been 'done'.  I have available - but have not fitted new springs - the existing springs seem 'ok'......I don't think new springs would have that much impact on things, although I appreciate they might apply marginally more pressure to the new pads to compress them  but I am not sure it will overcome the 1.5mm +/-  difference between current and 'new' buttons.  

 

It is probably worth mentioning that she was playing - within the limits of my ability ! and a few tuning issues - quite well, albeit with some re-glued original pads and re-glued pad faces, so I have an insight into her being 'worse' currently, than she was. 

 

 

Edited October 25, 2018 by Sprunghub

[Geoff Wooff]

Sprunghub,

 

I have this  thin  pad dilema  too;  on a  late  19th century  Wheatstone.  If I changed the  old thin pads  for  new  thick  ones  there would be virtually  no  room  for  lift off.  Even as the instrument is  I needed  to  remove  two felt washes  from underneath  each button  to  get max pad lift.  I did adjust the levers  to a position where  the  button guide pins are  just  in their location holes  and the pad ends  of the levers  are not quite touching the metal ends  at maximum  opening. The buttons  are  now  almost  disapearing  into the ends  when depressed.... and that is all with the original skinny pads.  I should say I was  trying to maximize  power output  on the  instrument  and  it is a  transitional ( or early)  Raised Metal End  model  where  the designers  had not allowed  much height in the action box.

I'd hate to think what I would need  to do  IF / and when  the  pads  need  changing............  make a set of thin pads  I guess.

 

But by the looks of your picture there should be enough room  to  bend the levers  and David Elliot  describes  how to do this in his book  on maintenance  and repair.

Edited October 25, 2018 by Geoff Wooff