My Frankenstein Thumb.

[Jonathan the 2nd]

The complicated prosthetics for fingers and thumbs can be simplified for the small finger. All the extension needs to do on a piano is press down not very hard . It should play white and black notes.The main adjustment in the finger from white to black notes comes from the second and third joint.If I make a kind of thimble to enclose the finger up to the 2nd joint and connected to a wrist band I may lose a tiny amount of flex in the first joint but with silicone cushioning that will not matter . The first joint will still move normally inside the thimble , but there will be no slackness at the fingertip or at the 2nd joint Then some elastic above and below the hand will stop the extension falling off and reduces any need to fix anything around the finger. It might need a few minutes of one finger exercises each day . So thimble , silicone ,elastic . How expensive could that be ?

[Jonathan the 2nd]

A very happy bit of seredipity came my way today . I have been plumbing in my own central heating system and needed a few copper junctions to do a pressure test. The shop sold me some wrong size parts today but one just happened to fit my small finger perfectly . A copper reducer from 22mm to 15mm acts as a long thimble with an open end. My finger tip is spot on the right size at 15mm and the wider 22mm end fits almost exactly right at the 2nd joint . So a litle lead free solder should see this small finger extension working very soon . being metal means there will be no flexing or wobble and the copper can be drilled to make it lighter. The extension part will be enclosed in a durable blob of silicone to protect the piano key surface .

[Jonathan the 2nd]

I have not played lately as I had a small accident with a drill making a hole through a brick wall . It twisted the right thumb and left it sore for a few weeks . However the small finger extension still needs a bit soldered on the end to make the extension . The fit around the finger is almost exact but needs to come in a fraction. Striking the keys will always tend to keep it in position and I shall make it as straight as possible . Any rotation then will not change it`s effectiveness . I want a snug fit without affecting the circulation . I can`t see a problem arising.It might be made lighter by drilling holes. As it stands it has almost no weight anyway .If I made holes I could use them for silicone rubber dimples going inwards. That would make it adaptable too .Fine tuning .

[Jonathan the 2nd]

In no way is this topic meant to be a conversation . Look on it as a notebook on a cure for small hands .
So today I was very encouraged with the first trial with copper plumbing joints to extend the small finger and also the thumb. This became more interesting because the small finger extension reaches as far as I want sideways but the thumb ,being a little short too allows the hand itself to settle too low . This means the small finger although reaching the octave easily is just moving the next lower note slightly . If I place my left forefinger below the thumb and raise it about one centimetre the octave can be played perfectly cleanly .
The reason I am pleased with today`s effort is the type of silicone rubber I have used inside the copper tube. It`s CT1 which is a popular diy glue/sealant . It sets as a firm flexible material but has a lot of tactile drag on the skin which makes it ideal to hold on the finger tips. The playing action continually pushes the "thimble " into the desired position and is unlikely to need any further attachment.
The CT1 as a material for the fingertip is ideal . It does not slide off the black keys and being silicone it will be very durable. The surface can be renewed indefinitely by applying the same material to itself .
Now that the metal shape seems so suitable I can already see a plastic version would be even better . That would make it much lighter .
When I began this topic I had not seen CT1 close up and it looks a better alternative to stretching my thumb joint and getting painful hands .

[Jonathan the 2nd]

I have realised one thing about my thumbs when playing piano . The hand being stretched apart shows the thumbs pointing sideways . This is a disadvantage with smaller hands as the piano keys dip downwards and the flattened hand and especially the thumb is most likely to interfere with the adjacent note.
I have lowered the small finger tip to cater for the key dip but the thumb needs a little extra attention . Each thumb is used on it`s side when playing so the angle of the piano key is at odds with the line of the extended thumb . So the copper thumb extender is fitted like a wide ring from the end joint and a small part of the copper extends past the thumb about one quarter inch to add on the silicone "blob" to act as the fingertip. This small addition is angled to suit the line of the piano key , rather than running across it too much .
Because the thumb joint is not "contained" or restricted it feels quite natural .
An odd thing about this metal and silicone combination is the way it "feels" the key . You get instant feedback on the lightest touch which is an improvement on using all silicone and flexible materials . I googled to see if anyone else had tried to make " finger extension for piano "and only found one question from 5 years ago . He received no encouragement at all poor chap . Anyway I have put the phrase in inverted commas so the magical internet may reach back to him one day .
Apart from these copper pipe "reducers" (correct technical description ) there are some plastic ones available which will be much easier to work (or play) with . Also the variety of silicones , medical or otherwise , should produce a workable result for not a lot of pennies .

[Jonathan the 2nd]

Three new changes have happened this week .
One negative was suddenly realising that silicone will not adhere to CT1 glue. So CT1 is officially dropped.
The most important change is for the small finger. The silicone is difficult to shape after it sets (or cures ) so to get the shape of a finger pad on the keys I carved out a nice smooth divot in some soft wood .I used the end grain and was able to rotate the gouge to get a smooth surface at the right depth . Then I rubbed beeswax into it to act as a release agent for the silicone. The copper "thimble" had a tiny spoon shaped extension soldered on and this was designed to be embedded in the silicone blob . The top of the blob being "loose" needed some shaping and I laid on a small patch of clingfilm and used a 1/2 inch brush to shape and coax it into a tidier form .
Looking at the one inch extension , the small finger first joint ,nearest the nail , needed some protection against bending backwards . This was done with a piece of copper 1/4 inch wide soldered on the top and reaching back to the second joint with another piece of silicone as a cushion against the skin .
I tried to use the minimum material to keep the weight down .This version seems to be very stable .
Padding the internal was a teaser. If you wrap the finger in clingfilm it gets wrinkley and ends up setting into the silicone. One way round that is to build the padding up in strips. Laying the flat clingfilm inside first , then squeezing in the silicone , pull the clingfilm over that and then place the finger inside for a few seconds , seems a nice dry way to go .
Checking the thumb addition I altered the position of the blob 10 degrees to be below the copper extension . It was facing a bit sideways as the hand was stretched over the keys . So just that tiny change gives a wider reach .
Drilling holes in the metal will be a final plus to make it as comfortable as possible .

[Jonathan the 2nd]

A technical leap forward came yesterday . How to line the inner surface of the copper tube for the small finger.
This is to create a layer of silicone between the copper and the finger. There is an opening at both ends so I started by wrapping my small finger in cling film to estimate the width needed. Then rolled that clingfilm round a marker pen . This was inserted in the copper tube .There was enough room to add the silicone and rotate the marker pen. Then the pen was withdrawn and carefully I inserted my finger inside the clingfilm. I imagined that would be difficult but it was very easy. I had enough time to get the extension centralised and then released my finger . Today the film was removed and I have a superb fit with a very stable feeling.Just wiggle the finger inside and it`s ready to go .
This is looking like a seriously practical solution for small handed players .

[Jonathan the 2nd]

I realise now how important octaves are in one Chopin Nocturne.Op 9 No 2 ( 4 bars from the end ) and listening to one recording I struggled to register the main tune. Maybe it was because it was not in Kirnberger III . I find Equal Temperament awful to listen to . But an Engerer recording made me realise I know this music from childhood. So how can a recording artist play all these notes and create an impenetrable fog so I can`t register what the tune is?