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[malcolmbebb]

I have a couple of broken Hohner fingerboards, with the web missing between several keys. Common damage, it seems. One is a pressed wood, the other an Erica.

I was wondering about repairing rather than replacing them. Is this viable - do you need to be a dab hand with a router?

Suggestions?

[Theo]

You could either:
Slice off the broken top, cut a replacement from ply, plastic or metal, cut button holes, drill and countersink screw holes
or
Carefully fit and glue patches into the broken areas, re-cut button holes, refinish the surface
or
Just buy some of the lovely replacement fingerboard from Acorn Instruments, they fit, it's easy to adjust button travel, (and I'm not on commission)
The old fingerboards make really good kindling for your wood stove:-)

[Ebor_fiddler]

Like!

[Graham Spencer]

or
Carefully fit and glue patches into the broken areas, re-cut button holes, refinish the surface

That's what I usually do; I generally use a piece of lime (linden in most of the rest of the world) as it's pale coloured, takes stain well and has very little discernible grain. Rather than try to glue in patches edge-to-edge, I first put in a backing piece of 1mm ply to provide plenty of gluing surface.

Graham

[Adam-T]

Good idea Graham, 1mm underneath  isn`t going to foul the button ....... sadly Acorn Instruments don`t make Club-One , Too/Erika , pre-Corso sizes ones (or tops for those with removable tops as few have the tools to accurately drill a new top well) or standard ones with pressed graphics so repair ideas are valuable .

I`m thankfully getting a used one for my Club Too from Robotmay when he`s dug it out but I`m going to have a go at gluing the old one and trial gap repair techniques on it (which now don`t matter if they fail)

[mr hohner]

Or build your own, hard work but satisfying
 

[Lars]

I've previously repaired a few keyboards, but I always made a removable back plate too, for ease of padding and adjusting. Removing some of the back surface makes it a lot easier to insert patches, and put reinforcing struts on the back, as the rather crude inner surface benefits from some sanding to ensure a good, flat surface.

Version one:
With a small router base (on a dremel-type router), rout out a rectangle 1 mm deep, covering the back of all buttons. Then, rout all the way through, leaving 5 mm all the way around for the panel to rest on. Cut 1 mm alu to the right size, fit to the countersunk 'hole', countersink screw holes and install with appropiate screws to the back, resting on the 5 mm 'shelf'. Install felt (you might want to put the felt on a 4 mm wooden strip to avoid having to install too high felt padding).

Version two:
On a router table, rout out a channel all the way across the back of the fingerboard, leaving about 1 cm at the edges towards the thumb and 'box' sides. Rout about 5-6 mm deep, depending on the plywood avaiable. Cut a strip of stiff ply or hardwood to fit the channel in a tight, snug fit, install with screw at the ends. If possible, rout with a slight angle, so the strip/panel fits in a dovetail manner. It will need to be contoured at the ends to match the keyboard, and naturally painted or stained. Install felt, and voila, your own removable back panel on an old wooden keyboard.

None of these are however a match for Pete and Jilly's Acorn keyboards. No commision here either, just a great product.

[mr hohner]

The hardest part of making key board I found was drilling the holes to the right size!!! To start of with I used a router ( I think that's what there called) to drill into solid oak. I then put a thin piece of wood between back and front and drilled the marked out holes (this requires real accuracy, I made lots of mistakes until I got it right)!!! I then used a dremnel mini sanding piece to make the holes the oval shape they need to be, this was time consuming but satisfying!!! If you have some spare time make your own keyboard, hard work but satisfying at the end!!!
Cheers
Mr hohner

[Broadland Boy]

Have you discovered lip and spur drills Mr H ? much easier to start accurately from a centre pop and cuts a much smoother hole, also a little more forgiving if the hole needs to be a little off 90 degrees to the surface.

[Theo]

And another tip is that it is not actually necessary to make the holes oval.   Hohner is the only maker I can think of that does this, and then only on some models. Most club models for example have circular holes.   I suspect the reason for the oval holes is that it saves having to make any individual adjustments to centralise buttons to avoid making contact with the edge of the hole.

[malcolmbebb]

On Hohner mechanisms you only have side to side adjustment (and height,of course), the length of the arms is fixed, so I have wondered why there is extra clearance in that direction. 

I should confess that I have a couple of Pete's fingerboards in waiting (and, unusually, know exactly where they are).
But I was thinking that, mainly for the presswood, it would be nice to keep the original if a repair was a sensible option.
If I do, the removable back seems a pretty good idea.

Not having a wood burner...

(Goes away to Google lip and spur drills - oh, those... wondered what they were called...)

[boxcall]

I went with the Insert method, I found the holes to be easy enough using a drill press with a fence that has center of drill marked on it. then layout holes on finger bd. and line up the marks when drilling.
I started at the top of the hole and drilled those then I put a small strip of wood between fence and finger bd. then drilled all holes again to elongate. cleanup holes with sand paper.
For the cut out in the finger board I use a router with flush cut bit( the ones with bearing on the top),
I cut a slot in a piece of quaility plywood (no voids) the size I wanted, then I lined up the finger bd. in the slot I just made in the plywood. I corraled the finger bd. with scraps of wood hot glued in place.
then clamped the lot down on to bench and cut out slot in fnger bd.
The strip with holes I cut out useing table saw and chop saw then I rounded corners by hand.
I also made a finger bd. out of cherry ( posted here somwhere) I sent it to another member.

seen here

http://forum.melodeon.net/index.php?action=dlattach;topic=16508.0;attach=16052


Edit: no layout on finger bd. needed in insert method as I just put strip in the slot in finger bd. , filled in the space inside the finger bd. with a backer for drilling and used the tick marks at base of finger bd. for layout when driling.

[mr hohner]

And another tip is that it is not actually necessary to make the holes oval.   Hohner is the only maker I can think of that does this, and then only on some models. Most club models for example have circular holes.   I suspect the reason for the oval holes is that it saves having to make any individual adjustments to centralise buttons to avoid making contact with the edge of the hole.

I've found that it gives the buttons some clearence to travel up and down at the slight angle there at, it seems to "run" smoother this way than when they were round.
Cheers
Mr hohner

[Theo]

On Hohner mechanisms you only have side to side adjustment (and height,of course), the length of the arms is fixed,

It can be adjusted by putting a kink in the lever, same as in Italian boxes.

[Adam-T]

Yeah, I`ve seen plenty of Coronas and corsos with curvy levers straighten them and the buttons are off centre

[malcolmbebb]

On Hohner mechanisms you only have side to side adjustment (and height,of course), the length of the arms is fixed,

It can be adjusted by putting a kink in the lever, same as in Italian boxes.

Ah. Hadn't met that.

[Graham Spencer]

And another tip is that it is not actually necessary to make the holes oval.   Hohner is the only maker I can think of that does this, and then only on some models. Most club models for example have circular holes.   I suspect the reason for the oval holes is that it saves having to make any individual adjustments to centralise buttons to avoid making contact with the edge of the hole.

Perfectly true; but if you're patching up an existing unit that already has elongated (they're actually not "oval" in the strict sense of the word) holes you really don't have a lot of choice other than to try and match them as closely as you can.

Graham

[pete /acorn]

Hi
For the pressed wood I supply them in the white [not painted]] to colour and polish yourselves.

Pete

www.acorninstruments.co.uk

[malcolmbebb]

Hi
For the pressed wood I supply them in the white [not painted]] to colour and polish yourselves.

Pete

www.acorninstruments.co.uk

I would describe the one I have as "natural" rather than "white"   

[pete /acorn]

''In the white'' is a term used in the furniture manufacturing industry to describe products as in natural state un painted or polished