Action Board Crack

[Stephen DOUGLASS]

I have noticed a couple of small cracks on the action board of my Crabb English. They seem to be 'slight' and don't go all the way through (But I might be just 'kiddin' myself). Is this something that should be repaired, or something I should keep monitoring? Thanks in anticipation.

[David Lay]

Monitor them, of course, but also monitor the humidity of your instrument's case.  If you live in an area where it gets very cold, moisture levels in the air can get very low.  Try to hold near 50% relative humidity at room temperatures.  There are guitar case humidity control packs available for this.  Wood objects are particularly vulnerable if they are moved from a place with a temperate climate to a place with a cold or arid climate.

All wood moves as it absorbs or gives up moisture.  If the movement is restrained, it will likely lead to cracking.  Plywood is more dimensionally stable and less affected.  Also, wood moves more in the direction perpendicular to the grain than in the longitudinal direction.

Edited February 11 by David Lay
Spelling

[David Lay]

Stephen.  Saw your prior post about humidifiers, so can see that you are dealing with it.  However, beware room humidification at 50% when it's very cold.  Moisture can damage your home at that level if it migrates into walls and condenses there or on cold surfaces.  That is the reason I prefer the case humidifiers.  As an architect, I have seen condensation damage too often.

[Stephen DOUGLASS]

50 minutes ago, David Lay said:

Stephen.  Saw your prior post about humidifiers, so can see that you are dealing with it.  However, beware room humidification at 50% when it's very cold.  Moisture can damage your home at that level if it migrates into walls and condenses there or on cold surfaces.  That is the reason I prefer the case humidifiers.  As an architect, I have seen condensation damage too often.

David, possibly I should change my tactics, up the ante... run room humidifier and ALSO use case humidifiers. We had a spate of brutally cold weather here (during which I couldn't get humidifier to run beyond 35%) and that may have contributed, but I suspect it may have been lurking in the wood waiting to happen. I did run out and buy a small case 'humid' that night for the box in question.

Edited February 11 by Stephen DOUGLASS

[Don Taylor]

If you are feeling really paranoid about humidity then you can also buy little bluetooth humidistats that will fit in the concertina case along with its little humidifier.  You can then monitor the humidity inside the case from your phone without opening the case.

[d.elliott]

These are shrinkage cracks, they should not be an air path because they have the action plate on the other face. I would rub white PVA wood glue into the cracks to stabilise them and fill the cracks. Leave 24 hrs to fully dry before reassembly. I usually feel that it's best to let the instrument settle to it's normal ambient environment, keeping it fully bolted up. if you get wood shrinkage then so be it, attend to it and you have a nice stable concertina. As long as the humidity and temperature swings are not enough to get major condensation on the reeds then no real harm will ensue.

 

I once had a concertina delivered to me for attention that had belonged to a missionary in India. It was presented to me in a velvet and horse hair padded fairly airtight tin box, black, picked out in gold and with the reverend gentleman's name in it. Once I managed to get the box open The instrument was nestled in a mass of rotted fibres, the veneering had sprung off the casing wood. The end bolts unscrewed I found the chamois in a brittle condition, the bellows, pads and valves fully rotted and the steel reed tongues corroded through to holes and stubs. It must have been a wonderful 'tina' at one time, but alas no more. I can only assume that the instrument had been packed in it's box whilst in India with all the local humidity in the leather, the velvet and it's padding and then stored for a long time in it's own microclimate. Not allowed to breathe and settle to whatever new climate the concertina was returned to. I guess that the moral is to acclimatise your instrument, and play it regularly.

 

[Stephen DOUGLASS]

Thanks for the good advice David. Coincidentally this concertina came from a Missionary who worked in China, though picked up London, and I believe brought to Maine on his retirement. It also needed work, as I think he passed shortly after arriving home to Maine and sat unused.  It was therefore pristine on the outside, but after opening, It did need some proper work. But is a lovely 'thing' now.

[SIMON GABRIELOW]

Wood as a material never really stops or ceases to change or move throughout its lifetime. It looks like the board has opened along naturally existing ray marks in the wood surface.. but wood is a very forgiving material in itself, and  you will have little difficulty in finding a solution to the problem. And, actually it does not look like a difficult job to cut a new board out, I would say, using the existing one as a template? ( Only a suggestion).

[d.elliott]

Simon,

 

its the wood grain, shrinkage occurs across the grain, not down it's length. once it has happened then the wood is generally stable, it is all about making sure that the item is fit for service. What you can see is the plain side of the pad board. what is on the other side would not want to be tampered with.