North Queensland Chess Board Question

[Chris Parks]

I was going to make my Grandson who lives in Cairns an end grain chessboard but speaking to my daughter she raised a few concerns. Firstly she is worried it might warp and the next problem was what to finish with to prevent mould growing on it. Any comments from those who know the climate up there? Would a standard poly prevent mould growth?

[auscab]

Hi Chris .
Solid thick end grain will move.
If you keep the dry end grain pieces thin like 3 or 4mm and glue it to something like a 18mm ply with two pack, then finish the edges with a mitred solid edge it won’t move . I’d then fill the grain with an oil based sanding sealer and finish with a coat or two of shellac . When dry give a rubber of shellac and tharen a wax .

Sealed and polished with any product then kept clean will stop mould I think . Mould forms more when a surface is absorbent enough to hold moisture in it and the temperature is right and then the right bug moves in to the cosy home you left for it . But then I ask myself “ Why does mould form on a bathroom tile” ? Must be because enough scum has been left on the tile ?

Rob

[Chris Parks]

Thanks for the post Rob. I have never lived in the tropics so these things did not occur to me. A thinnish end grain veneer sounds like a better proposition than my original idea.

[Aussiephil]

Spent a few summer months up there as well as a winter time holiday over the years and i was first going to reply there is wet and dry.... the reality based on real climate data is not so clear cut and becomes more about the local house conditions and do they run air conditioning at all.

The climate averages for relative humidity surprised me with exactly how consistent it was and this should lead to great timber stability, sort of the opposite of expectations
Cairns historical data, black bars, high but consistently high
cairns.jpeg

The surprise comes when compared to helensburg that apart from the odd low month is only 10-15 % lower .... the greater swings you have at home should lead to greater wood movement than experienced in cairns.
helensburgh.jpeg

Data courtesy of
Helensburgh, New South Wales, Australia Weather Averages | Monthly Average High and Low Temperature | Average Precipitation and Rainfall days | World Weather Online
Cairns, Queensland, Australia Weather Averages | Monthly Average High and Low Temperature | Average Precipitation and Rainfall days | World Weather Online

I would even debate if the swings you would get locally would cause much change in seasoned and or oiled wood.

As for the finish, yeah mold can be a concern during the wet season as things don't seem to get dry up there but that is more about lack of air movement in many of the modern development areas, a few of the places we have looked at (to buy) have been in areas with no breeze.... It's a chess board, i'd finish it the same as a cutting board with a good soaking in food safe oil, makes it easy to refinish.

[tony_A]

I made a blackwood / huon pine end grain chess board a bit over 12 months ago. 40 mm squares with an overall thickness of about 50 mm. (sorry, no photos). It has survived 12 months in far NW Tassie in one piece and apart from a small crack that appeared in the first month. Im putting that crack down to shrinkage on the edge as the timber wasn't kiln dried. I was rather nervous and relieved to hear recently that cracking has not been a problem. In construction I tried to use quarter sawn pieces and had all the grain running in the same direction. Radial and tangential shrinkage rates are different. If doing another I would cut the a glued up strips of alternating timber to final length and leave for a few weeks before the final glue up.
Finished with Ubeaut white shellac and traditional wax.
It did look stunning, even if I say so my self.

[powderpost]

I live in the tropics, in fact 65k from Cairns, as well as that I have built numerous chess boards. They were made using exterior ply as the substrate and veneered both sides to balance the construction. I can't see a problem using "solid" timber blocks for the squares except that the pieces should be up to 2mm thick, maximum, thinner if possible. It doesn't matter what coating you use, you will not stop timber moving. Painted joinery will move, even if it has several coats of paint, either water or oil based paints, it doesn't matter. The amount of movement in a chess board shouldn't cause major a problem.
Mold will form on anything in the tropics, the key is not to hide the piece in a cupboard with out adequate ventilation and even
better is regular use.

Jim