Tuesday, 7 May 2019

Pride, Prejudice and Pianos

The Hamilton action arrived in Kigali and we've set to work on it. We measure time by how many movies you get through whilst you work. It's been nice listening to the piano music in Pride and Prejudice whilst putting one back together.

It's the long wet season at the moment:


But when the weather's nice, we sometimes work outside.


With the help of assistants.

Akantu ('little thing') and Gizmo

The main problem with the piano action is sticking hammers. It came from Tanzania where it caught a bit of humidity. The hammers move forward and backwards on tiny metal pins. The pins sit in holes padded with felt. If the felt gets damp, it expands, and this causes the pins to tighten up and the hammers to stick. One way to check for sticking hammers is to push the hammers forward and see how smoothly they return. This Kimball is in good shape:


If they return slowly or not at all, there's probably a tight pin. Though also check the hammer hasn't just got caught on the damper felt, which can happen if the action is out of the piano.

Fixing sticking hammers can be quite an undertaking and requires removing the hammers from the action frame.We made a little video on how to do that here

We also had to replace 35 bridle straps, which had been chewed on at some point in the past.

Whippens

Hammers
Dampers

It's important to number everything with pencil or chalk as you take it out, so you remember where to put everything back. Things can get complicated quickly...

 
And a little bit of Blu Tack can go a long way. Especially in stopping errant screws from rolling across the floor and disappearing under couches.


Once the hammers were off, we used this handy pin poker and bushing broach kit to loosen up the felt. The poker pokes the pin out of the hole, which can be quite tough if it's in really tight. Pliers help once the top of the pin is far enough out. Then the broaching kit is made up of thin pokers with a rough edge to brush the felt loose. After that, you can gently tap the pin back in and the hammer should move smoothly again. 


1.27 mm/0.05" Flange Pin
Broaching Tool, Brushing the Felt
This has worked well for most of the faulty hammers, all except one which has too loose a flange. This means the felt isn't tight enough because it's worn down, resulting in a hammer that wobbles from side to side and doesn't strike true. 

Unfortunately - we have a problem. We tried re-felting the hole with the thickest felt we had, but this wasn't enough to solve the problem. It needs a larger pin. That's something we haven't got access to. Online shops sell bags of centre pins for around $11 before postage, but the sizes are so exact and if we order a big bag of the wrong size, and they don't fit, we have no other use for them at the moment. We're appealing to piano refurbishers to post us a selection of sizes. Every piano we encounter here comes from a different part of the world, with different specifications. We could really do with a little collection of centre pins for emergencies. The pin we need to replace is 1.27 mm/0.05", so the next two sizes up from that would be helpful, and then whatever else you have to spare.

Our address is:

Marion Grace Woolley
PO Box 5145
Kigali
Rwanda

It can take several weeks for things to arrive, but we're always extremely grateful.  
We've done all that we can outside the piano now, and need to return it to the instrument to check whether the fixes have worked. 


On a final note, we found this on the back of the action. The Piano Age Calculator reckoned this was made between 1947-52, and this appears to back that up. It seems to say 8.12.52 - EW. This might be the first time it was tuned, but it's compelling evidence that the instrument was indeed around by 1952. As it's an American make, that's probably 12 August 1952, rather than the British date system of 8 December 1952.

No comments:

Post a comment