Bringing an old Hohner back to life

I recently acquired this very rough looking two row Hohner.  It looks so horrible I thought it would be fun to document the process of returning it to full playing condition.  Here are some pictures showing the condition as found.

The bad points are:
  • its filthy
  • the grill is rusty
  • valves are curled up and the reed wax is failing
  • treble reed blocks have shifted out of line
  • one of the glue blocks is missing that should locate the treble blocks.
  • one treble reed block has the base plate breaking away
  • keyboard top is broken, has been repaired, and the repair is broken.
  • leather straps are crumbling
  • celluloid finish is stained and faded
On the plus side:
  • bellows are airtight, which is very unusual for a box in this state
  • the woodwork of the case is sound
  • the original bellows lining paper has a great black and red pattern
  • it’s in Bb/Eb and no reeds are broken as far as I can see and any rust is very light
  • no major parts are missing
Disassembly and cleaning

Now I start work by stripping down and cleaning everything to assess what work is needed.  I will replace that tan leather bass strap.  It is very unpleasant looking and is as stiff as cardboard.  I’ll also replace the damaged keyboard.  There is a broken spring on the treble mechanism.  Once the thick accumulation of dirt is removed it all looks sound.  No sign of dampness ever having affected the woodwork or bellows, and no sign of woodworm. Cleaning the pallets and removing old leather shows the wood there is also sound.

More cleaning

The celluloid looked very dull and I though it might be faded from exposure to sunlight.  On closer inspection I’m pleased to see it is just very dirty.  With some mildly abrasive polish designed for use on plastics it cleans up beautifully.

Bushing bass buttons

One source of mechanical noise is from the hard plastic bass buttons making contact with the holes they travel in.  My solution is to ream out the holes to give space for a felt bush lining the holes.  I also dispense with the felt washer behind the button.  I leave the bush slightly proud of the surface so that the flange on the button is stopped by the raise felt before it can touch the hard surface below. The material I use is woven felt about 1.2mm thick.  I cut it on the bias to prevent fraying and make a rectangle long enough to go once round the inside of the reamed hole without gap or overlap.  The felt is glued in with pva and then pressed firmly into place with a tapered rod.

Re-assembly

The box is now back together again.  Reeds fitted with new valves, re-waxed and tuned.  I replaced the keyboard with a good one of similar vintage, and replaced the rusty grill with a spare one of the same pattern with its nickel plating still in good condition. The finished box is now for sale.

Boyd Wheatstone rebuild

A friend has been searching for one of the legendary Wheatstone English concertinas commissioned by Harry Boyd who ran a music shop in Newgate St, Newcastle at the turn of the 19th century.  Last year he finally found one, which had originally belonged to Tom Prince a renowned player from Consett, Co Durham.

I’ve been asked to refurbish the concertina.  As found it has new bellows, and all the notes play, but it is somewhat sad a scruffy looking with improvised thumb straps, end bolts adapted from a different instrument, and the ebony end frames surrounding the fretwork are badly worn, and many have been replaced with non matching timber.  Its going to need the usual replacement of pads and valves, at least six new end bolts, new straps, cleaning and polishing of the metalwork and tuning.  But the major task is to replace the moulded ebony rail round the ends.   I did consider trying to repair what is there, but there is really very little of the original left and its going to be a better end result to replace rather than repair.

Preciosa 12 bass part 2

This stage covers the modifications to the bass action.

Preciosa bushed holes for bass buttons
Preciosa bushed holes for bass buttonsThe new bass plate fitted in place after marking out and drilling 12 holes on a rectangular grid.   The holes are reamed to about 10mm to accommodate an 8mm button and .9mm bushing of woven felt.  The holes are slightly conical getting larger towards the inside of the box to keep a good fit on the outside, but to allow some tolerance in alignment of the axis of the button with the axis of the hole. I borrowed this technique from concertina construction.

Next task is to reconfigure the mechanism to pair up bass and chord melodeon style (vertically) rather than stradella style.

Regina 1 Bass mechanism
Regina 1 Bass mechanism

This is the stradella mechanism, also showing the air button which is badly placed for melodeon playing, more of that later.

The pallets also need to be re-faced so I’ll do them while the mechanism is out of the way.

I’m hoping I can reuse the wire rods and just shift them to different positions.

Several of the button rods snapped when straightening the end to detach from the lever

So it will have to be new rods then.  The buttons are real mother of pearl so I’ll need to be careful to avoid damage when removing them.  Gentle heating with a gas flame softens the original adhesive which looks like shellac and they pull of easily.

Fortunately the rods are made of 1.5mm steel wire, exactly the same material as thin filler rod for gas welding which I have a stack of.  So its down to a couple of hours of careful bending and fitting to get the new rods made and installed.

Levers ready to accept pallets and rods
First levers fitted
Regina 1 Bass mechanism
All the new levers formed and fitted.

Now its time for the reeds.

The reed work was fairly straightforward because the client has his own custom layout which is partly unisonoric and has no thirds in the chords. The D/G version of this layout is available here on melodeon.net.The unisonoric notes were able to use the original unisonoric accordion reeds as they were.  The chords each have three reeds either tonic+fifth+tonic, or fifth+tonic+fifth,   the choice being used to keep all the chord reeds within a compass of one octave.

Finally, I fitted a catch for the bellows lock to the bass block, replaced bellows gaskets and one or two other minor bits of tidying up and the job is done.

I found Clive’s unisonoric layout is very easy to adapt to after  only playing conventional melodeon basses.

Here is Clive’s response after receiving the converted instrument:

.. and here it is, all done, in action!

It’s a *fabulous* box to play; light, fast, great sound, and as flexible as my Mory (it’s got the same semi-unisonoric layout on the basses). It’s in Bb/Eb of course.

And these are the tunes that came out when it said hello: The Wrong Turn is a waltz/mazurka thingy written by Anne Marie Summers, English bagpiper, probably best known for her duo with Stephen Tyler on Hurdy Gurdy, and the trio Wendigo (with Julian Sutton). Played from *distant* memory, so it’s probably some way away from the original tune! The Sportsman’s is a traditional tune, and one I’ve known for ages, but only recently come back to playing after we’ve started using it in our Vivant stuff (slower than I play it here).

Thanks Theo!

Clive

Preciosa 12 bass part 1

This project to convert an 8 bass Hohner Preciosa to 12 bass by uniting the treble side of a Hohner Preciosa with the bass side from a Hohner Regina piano accordion.  here are the two boxes at the start of the project.

The donor Hohner Preciosa and Hohner Regina

Fortunately the bellows are identical so its very quick to do this:

Preciosa treble joined to Regina 12 bass

But that’s not quite all there is to do.   The arrangement of the bass buttons has to be completely changed.  The buttons are to altered to a retabgular grid, instead of the skewed pattern at present.  The function of the buttons also has to be changed from a stradella system, to a custom melodeon system.  This will require modifications to the reeds, and to the mechanism that connects the buttons to the reeds.

First task is to make a new button panel to replace the one with skewed button layout.  Removing the old panel is nice and easy because it is glued in with that wonderful substance: hide/scotch/animal glue.  It softems in water so just apply some water to the joints, leave for half an hour, scraping off the surface glue after a while and eventually it comes out without damage.

Soaking the glue prior to removing the button board.
Glue released

Now to prepare the replacement.  A suitable piece of plywood which should be less prone to distort than the original, and some white pearloid that is not quite an exact match, but pretty close.

Replacement material, plywood and celluloid.

To glue these together I simply flood the surface of the wood with acetone, place the pearloid sheet on top, and clamp for a couple of hours in this wonderful book press.

Book press

Then with a bit of measuring and four cuts on the saw we have the new board ready to mark out and drill.

New button board cut to size

Contined in Part 2.

Lachenal Anglo restoration

Done a few years back this is a sequence of photos that documents the restoration of a mahogany ended 30 button anglo that had many common woodwork defects. These had to be put right before there was a chance it would play properly.

crack in action board
The action boards had several shrinkage cracks like this one. These are common, especially in cheaper instruments made with badly seasoned timber.
First stage in repairing the cracks is to glue in slips of wood, actually I used pieces of veneer for these cracks…
open joints
Shrinkage can also lead to failure of glued joints here leading to large gaps opening up between the action board and the frame.
… and slightly thicker pieces for the open joints.
Buttons before and after cleaning
Buttons before and after cleaning. The top row of buttons are as found with a thick accumulation of dirt. The bottom row have been cleaned by scrubbing with detergent solution.