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[Telemorris]

I'm making a melodeon for myself, as some of you know.

I need to build a register for my bass reed blocks. One register or stop for the fundamentals to remove the lowest bass, and another to remove the thirds from the chord reed block. I haven't got any examples in hand of wooden registers, only photos. I'd like to make a wood register/stop for each reed block. How thick are the strips of wood usually? What kind of wood are they made from? Are they usually the same species of wood as the bottom plate of the reed block?

Also, a design question. The photos I've seen of registers seem to show the top and bottom surfaces of the wooden register slide against the wood of the soundboard on one side and the reed block bottom plate on the other, a sandwich if you will. There is usually a leather, felt or piece of cork used as a gasket to either side of the register slot. Please correct my assumption here: the hold down screws provide a certain amount of pressure that allows you to dial in the pressure placed on the register, creating a seal yet still allowing some movement. Is this correct? Is there ever a gasket of some kind that the register slides against?

Last question: For the stop that slides through the case wall and activates the register, how is this sealed to prevent air leakage? Is it simply a hole drilled the same diameter as a metal or wood shaft (or marginally smaller) to allow for movement? Is there a gasket of some kind? If so, what material is the gasket made from?

Thanks in advance.

[Peter Stormy Hyde]

I'm making a melodeon for myself, as some of you know.

I need to build a register for my bass reed blocks. One register or stop for the fundamentals to remove the lowest bass, and another to remove the thirds from the chord reed block. I haven't got any examples in hand of wooden registers, only photos. I'd like to make a wood register/stop for each reed block. How thick are the strips of wood usually? What kind of wood are they made from? Are they usually the same species of wood as the bottom plate of the reed block?

Also, a design question. The photos I've seen of registers seem to show the top and bottom surfaces of the wooden register slide against the wood of the soundboard on one side and the reed block bottom plate on the other, a sandwich if you will. There is usually a leather, felt or piece of cork used as a gasket to either side of the register slot. Please correct my assumption here: the hold down screws provide a certain amount of pressure that allows you to dial in the pressure placed on the register, creating a seal yet still allowing some movement. Is this correct? Is there ever a gasket of some kind that the register slides against?

Last question: For the stop that slides through the case wall and activates the register, how is this sealed to prevent air leakage? Is it simply a hole drilled the same diameter as a metal or wood shaft (or marginally smaller) to allow for movement? Is there a gasket of some kind? If so, what material is the gasket made from?

Thanks in advance.

There are a few things you have to ask yourself first (you may already done so) What size is the box? If you want to get 2 slides in it would have to be at least 150mm wide, if the box is less then you can normally get one slide in for the 3rd, at 140 mm wide it is possible to get the lower fundamental slide in but I found the extra 10 mm's makes all the difference for valve clearance within the bellows. It pays to have the low fundamental at the back. I slope the chord block back 5 deg's and the fundamental block back 9 deg's. The Low fundamental needs to be at the back to keep the separation from the slides, and as I have the bass strap adjuster pass through the pallet board the slide would run into trouble if it was on the front of the reed block.

For the slide I would suggest either 2 mm rock maple or 1 mm brass, here comes that fret saw again to cut out the holes, you can use aluminum as well but it clogs the saw blades.
Again you have to think about whether you want to make a small accordion or a big one, if a small one you will need a 3 voice harmony (as I only use) or a 4 voice harmony where you will need to make the box bigger.

My slides are 1 mm aluminum and I have had them made in Italy, now this is going to upset the purests but it works very well and is stable, I use 1mm thick low acid  art board as guides and is so easy to cut on my guillotine (I firstly spray the sheet with lacquer on one side first, this will become the exposed side and will have the leather up against it) that I glue down on to the pallet board to run the slides in, I used to use timber or ply here and found it very fiddly, as it normally had to be sanded down to height. I then put leather on the reed block (pig skin), I do this by stapling the leather and the paper template down to a soft plastic cutting board then I cut out the holes using chisels, then I take off the template and put glue on the reed block shoes and drop them down into place.

As far as the stop through the frame just make it an exact fit and then put candle wax on the stop shank.
If you have any trouble here let me know and I will send you a few photos that should help you.
Peter

[diatonix]

I think you should consider using airplane plywood. You can make your "soundboard" from different layers, if the middle layer is made from, say 1mm ply, you can make the slides in 0.8mm. Use a scroll saw and cut your holes through all layers, incl. the slide, in one go. Rough edges are easily sanded afterwards.

[Theo]

I've also used aircraft ply slides to fit slides to existing boxes that lack them.  Cut two guide strips of the same material and glue to the edge of the underside of the block to form a housing for the slide that is automatically the correct depth.

[Steve_freereeder]

Cut two guide strips of the same material and glue to the edge of the underside of the block to form a housing for the slide that is automatically the correct depth.

Theo - as an aside, if you do that, the reed block will no longer form an airtight seal when placed on the flat surface of a tuning table for subsequent tuning at a point in the future. How do you get around that please? (a) modify the surface of the tuning table with a similarly raised portion so that the reed block fits over it? or (b) tune with the reed block in-situ in the instrument? or (c) some other cunning method which I know you are good at thinking up? 

[Theo]

(c) some other cunning method which I know you are good at thinking up? 

I use small scraps of bellows gasket across the housing and between each of the openings to make an airtight seal.  Cunning or what?

Hmm, no emoticon for cunning

[diatonix]

Sorry for answering without being asked, but: all fine-tuning should be done with the blocks in situ.

[Steve_freereeder]

(c) some other cunning method which I know you are good at thinking up? 

I use small scraps of bellows gasket across the housing and between each of the openings to make an airtight seal.  Cunning or what?

Hmm, no emoticon for cunning

Thanks, Theo. I knew you would have a cunning plan! 

Sorry for answering without being asked, but: all fine-tuning should be done with the blocks in situ.

No worries, thanks for jumping in. I am aware of this, and try to do it where possible.

[Theo]

Sorry for answering without being asked, but: all fine-tuning should be done with the blocks in situ.

Agreed, but sometimes it is convenient to start with them on the bench.

[Telemorris]

Wonderful responses all round. Thank you very much!

Theo, could you post a photo of the "bits of gasket" attached to the reed block base plate, please? I'm having a hard time picturing this. Does the register seal against the bits of gasket?

Thanks,

Ed

[Theo]

Sorry I don't have one here to photograph at present, bit it was just a quick improvised fix,  nothing of any great significance.

[Telemorris]

[snip] ... I then put leather on the reed block (pig skin), I do this by stapling the leather and the paper template down to a soft plastic cutting board then I cut out the holes using chisels, then I take off the template and put glue on the reed block shoes and drop them down into place.

This leads me to another question: Which side of the leather do you glue to the reed block shoe? Do you get a better airtight seal if you glue the skin side to the wood?

Related to this: which side of the leather is best to glue to bellows card stock when you're making new bellows? I've been looking through the archives and can't find this info though I'm sure it must be there.

[Theo]

If I used leather for this I would glue the sking side to the wood and leave the nap exposed.  I don't usually use leather though, I prefer the synthetic material sold for the purpose by Carini.  Also I cut the holes after gluing it in place.  Just glue the block to the material, then when its set use a scalpel to cut the holes.  The reedblock bass acts as an excellent template, and there is no worry about lining up the holes or of the material stretching while you glue it in place.   If making new blocks it might be easier to glue the material to the wood before cutting the holes in the wood.

[Telemorris]

If I used leather for this I would glue the sking side to the wood and leave the nap exposed.  I don't usually use leather though, I prefer the synthetic material sold for the purpose by Carini.  Also I cut the holes after gluing it in place.  Just glue the block to the material, then when its set use a scalpel to cut the holes.  The reedblock bass acts as an excellent template, and there is no worry about lining up the holes or of the material stretching while you glue it in place.   If making new blocks it might be easier to glue the material to the wood before cutting the holes in the wood.

Thanks Theo,

I've used the fabric material you sent me, leather, and felt in various experiments trying to drill the holes for new block base plates. For some reason I never was able to get any of the materials to cut cleanly. I'll probably stick with drilling the wood or plywood first, gluing the gasket material on then cutting the holes with a sharp knife or scalpel. I might experiment with Peter's technique sometime if I'm going to be making a large, three voice instrument, however I can see that getting the precut holes to register properly might be an issue.

Anyone know how Castagnari or Loffett do this particular cutting job?

Ed

[Peter Stormy Hyde]

If I used leather for this I would glue the sking side to the wood and leave the nap exposed.  I don't usually use leather though, I prefer the synthetic material sold for the purpose by Carini.  Also I cut the holes after gluing it in place.  Just glue the block to the material, then when its set use a scalpel to cut the holes.  The reedblock bass acts as an excellent template, and there is no worry about lining up the holes or of the material stretching while you glue it in place.   If making new blocks it might be easier to glue the material to the wood before cutting the holes in the wood.

Thanks Theo,

I've used the fabric material you sent me, leather, and felt in various experiments trying to drill the holes for new block base plates. For some reason I never was able to get any of the materials to cut cleanly. I'll probably stick with drilling the wood or plywood first, gluing the gasket material on then cutting the holes with a sharp knife or scalpel. I might experiment with Peter's technique sometime if I'm going to be making a large, three voice instrument, however I can see that getting the precut holes to register properly might be an issue.

Anyone know how Castagnari or Loffett do this particular cutting job?


Ed

The problem with scalpels is the drag even if they are very sharp, this can be helped by stretching the leather out and stapling down on the cutting board.

As all my holes are either rectangular or square then I have a selection of double edged (that is one edge front and back) chisels, nice and sharp from my water wheel that i have made up for this job. You only have to bear down on it slightly to get a good clean cut, and as the you are bearing straight down on it you can do about 5 thicknesses at the same time. Start looking around the junk shops for those good old chisels that are to rusty for people to bother with, then grind down a double edge, they are not much good for wood work but are fantastic for this job.

The pig skin I get off the shelf is in fact a skiver so it is nap both sides, more than just handy.

At one stage I had punches made up to do the job, but that turned out to be a dead loss, and a wast of money.
Peter

[Telemorris]

Double edged chisel? Please post a photo. I do have scrap chisels that might be serviceable but I've never run into one that is double edged.

Peter, when you're cutting/drilling the holes in the soundboard and the corresponding reed block base plate, how do you do it? I've been using a standard drill bit in my drill press as the best way. I've tried Forstner bits, spade bits, all with varying success at cutting a clean hole. How are you cutting square or rectangular holes, especially in the sound board?

Thanks!

Ed

[Peter Stormy Hyde]

Double edged chisel? Please post a photo. I do have scrap chisels that might be serviceable but I've never run into one that is double edged.

Peter, when you're cutting/drilling the holes in the soundboard and the corresponding reed block base plate, how do you do it? I've been using a standard drill bit in my drill press as the best way. I've tried Forstner bits, spade bits, all with varying success at cutting a clean hole. How are you cutting square or rectangular holes, especially in the sound board?

Thanks!

Ed

I think that when all of us started making boxes we started out with round holes, and we run into the same problems, its very hard to get a good clean hole with a drill bit, one way is to use the router (I use the small one in the drill stand for that job,) and make up templates and jigs, but this is a lot of work and would slow you up a lot at this stage. My suggestion have another look at that fret saw, re draw your templates with 8x10mm holes and then cut them out using a fret saw, but you will need a deep throat mine is 320mm. This way may be a little slower than drilling but the end result is easier to live with.

When I make the soundboard and reed block shoes i place them and the board for the slides into a jig at the same time, so they all get cut out together.

You are very unlikely to run into a chisel ground that way (although I think they may make them for turning,)  the only reason I did it,  when you are cutting into a stack the chisel does not run off, it is not needed for a single thickness.  All you do to grind it is to put another 25 deg on the back edge, I will send a photo later if you still need it, as I'm about too rush out now

PS the mortice chisel is better, not the ones with the bevel down the edge.

Peter

[Telemorris]

Thanks Peter,

Now I understand about the double edged chisel. I looked online and found some very strange looking chisels and wondered.

I may just rig up a fret saw for the next box. Too many jigs at the present time, and I keep making more.

Thanks,

Ed

[Graham Spencer]

You are very unlikely to run into a chisel ground that way (although I think they may make them for turning,)  the only reason I did it,  when you are cutting into a stack the chisel does not run off, it is not needed for a single thickness.  All you do to grind it is to put another 25 deg on the back edge, I will send a photo later if you still need it, as I'm about too rush out now

PS the mortice chisel is better, not the ones with the bevel down the edge.

Peter

I guess by "double-edged" you mean "double-bevelled" - ie with a bevel on both sides of the cutting edge.  Such chisels are indeed used routinely in woodturning, though they are generally called "skew chisels" because the cutting edge is ground at an angle of about 10-15 deg across the blade rather than at 90 deg, which is what I assume you have done, Peter. You should be able to pick these up cheaply in a variety of sizes at markets, boot sales etc, and it's a simple job to regrind them to 90 deg.  They will also have a square-edged blade like a mortice chisel. Incidentally, I presume you grind a simple bevel on each side like a turning tool, and don't apply a steeper secondary bevel at the cutting edge?

Graham

[Andy in Vermont]

They will also have a square-edged blade like a mortice chisel. Incidentally, I presume you grind a simple bevel on each side like a turning tool, and don't apply a steeper secondary bevel at the cutting edge?

Straight carving chisel also usually have a double bevel, by which I mean a bevel on each side of the blade, rather than a secondary bevel on the same side.
Reading Peter's post, however, I'm not clear on why he needs the back bevel, as opposed to the straight (non-beveled) face of a chisel. Has anyone tried using a "corner chisel" for this same job?