Action board crack

[Chris Ghent]

On 3/30/2025 at 6:38 AM, Tiposx said:

Interesting. I wonder if Lachenal were intentionally using cheaper timber, perhaps not seasoned properly. The lower end models seem prone to  cracked boards. 

Lachenal wood looks cheaper to me.  I don’t see the typical signs of being quarter sawn. 

[David Lay]

8 hours ago, Chris Ghent said:

Lachenal wood looks cheaper to me.  I don’t see the typical signs of being quarter sawn. 

I would not expect quartersawn pieces to be more stable than plainsawn.  I would expect less cupping/warping, however.  Many modern makers make or use laminate boards for the larger pieces in a concertina to avoid dimensional changes.  Dana Johnson used a resin impregnated wood for his frames because of its stability.  Can someone tell us when makers started laminating their boards?  I wonder specifically (because of the fretwork) whether and when laminated end boards became common.

Edited May 11 by David Lay

[Jake Middleton-Metcalfe]

3 hours ago, David Lay said:

I would not expect quartersawn pieces to be more stable than plainsawn.  I would expect less cupping/warping, however.  Many modern makers make or use laminate boards for the larger pieces in a concertina to avoid dimensional changes.  Dana Johnson used a resin impregnated wood for his frames because of its stability.  Can someone tell us when makers started laminating their boards?  I wonder specifically (because of the fretwork) whether and when laminated end boards became common.

The warping can be really severe in some cases when quartersawn isn't used for the pad board. With regards to the fretworked ends of the instrument though all of the top notch instruments (Aeolas, Edeophones and some nicer wooden ended Anglos) had laminate ends made from multiple layers of veneers glued up. I'm not actually sure when this became the norm. The reason they did this is the end is going to be really fragile if you cut a complex thing pattern out of regular solid hardwood (because of how the grain of the wood interacts with the pattern).

 

Simpler patterns cut out of solid wood like some of the circular patterns on English system concertinas are less of a problem but still cracks are common.

 

Before I started making concertinas I made a prototype action box with solid walnut ends and cut out a pattern very similar to a rosewood lachenal Anglo, Colin Dipper saw this and kindly pointed out that I should have started with a laminated board as did the lachenal Anglo I was basing it on. Part of the fretwork had already cracked... Lesson learned.