Reed Chamber Valve Pins

[Mike Hulme]

I'm currently routing out the reed pan slots for the chamber walls of my Anglo. Is the normal course of action to install the valve restraint pins before assembly, and what are the recommendations for the pins themselves?

 

Mike

[alex_holden]

I don't know what anyone else does but I install mine as the final step of making the pans, after I've glued the valves in. I use 20SWG stainless steel spring wire, with one end ground to a needle point (makes it way easier to push them in).

[Bill Crossland]

Like Alex, I put the pins in afterwards, but use brass wire (for no other reason that it was dood enough for the old makers.

 

But, a supplementary question - what wood to use as the chamber separators? I've used 1.6 or 2mm aircratft ply for the treble and the baritone anglos I've made, and it has been suggested by various people who have seen/played them that the ply may have a sound deadening effect. I'm in the process of remaking the treble and am intending to try a solid wood partition. Should it be a tonewood, or does it matter? The old makers appear to have used sycamore or something similar....

[Mike Hulme]

Thanks, Alex and Bill.

 

I'll get some spring wire and see how that goes.

 

Bill - I am using maple viola ribs for my chambers.  It comes as 2 mm strips and fits snugly into the slot. I'm using rabbit skin glue on the chambers, with balsa guides to keep them perpendicular while drying.

 

Mike

 

 

[alex_holden]

8 hours ago, Bill Crossland said:

But, a supplementary question - what wood to use as the chamber separators? I've used 1.6 or 2mm aircratft ply for the treble and the baritone anglos I've made, and it has been suggested by various people who have seen/played them that the ply may have a sound deadening effect. I'm in the process of remaking the treble and am intending to try a solid wood partition. Should it be a tonewood, or does it matter? The old makers appear to have used sycamore or something similar....

 

On most of them I've used 2mm sycamore. I went down to 1.5mm on one instrument for space saving reasons but they seemed a little flimsy. I bandsaw strips from solid wood, then thickness them with a Byrnes mini thickness sander. Before I upgraded to the Byrnes I used an improvised copy of "The Luthier's Friend" drill press attachment.

 

8 hours ago, Bill Crossland said:

Like Alex, I put the pins in afterwards, but use brass wire (for no other reason that it was dood enough for the old makers.

 

Most of the vintage ones I've worked on had what looked like steel sewing pins or tiny nails, often quite rusty. On my first instrument I copied this and used sewing pins clipped short, which saves effort because you don't have to grind the point on them yourself.

[Bill Crossland]

Thanks both.Sorry Alex, you are right, steel rather than brass on old instruments, brain fade on my part. I usually have lots of bits of brass wire left over from spring making which fit the bill -  I cut them on an acute angle to get a sharper point, rather than grinding them, but do sometimes struggle to get them in without a curse or two..... 

Edited March 17, 2020 by Bill Crossland
Typo

[Alex West]

Just for badness, I thought I'd let you know that the Lachenal Duet I'm working on at the moment seems to have brass pins!  I'm pretty sure that there would be no particular reason why they would have used steel or brass - much like us all, they just used what was convenient (although the brass pins obviously won't rust).

 

And as an aside, the chamber walls are nominally between 1.5 and 1.75mm thick but there are quite a few where the wall has been thinned down - almost to a vanishing point - in order to slide the reeds shoes and clamp screws in.  There's usually quite a sound difference between concertinas with a lot of reeds crammed in and those with fewer reeds and more space in the chambers/less wood butchery; I'd always thought that was related to chamber size rather than wall material and thickness but I guess it could be a combination of things

 

Alex West

[Bill Crossland]

And I've just started work on an Aeola with brass pins. Maybe the brain fades in and out as required......