Fixing Ebony pieces with small cracks...

Just letting folks know some solutions for this. I have been doing this for years and have much success in drier climates repairing these. What I do is:

1. Inspect the pieces semi-regularly when new or after each year of non-use.
2. Where cracked, if caught early enough, easy way to "reverse" this is to wet with a small amount of water on a moistened Q-tip. The idea is to integrate a small amount of moisture back into the wood to have it re-swell in the area; don't get crazy, but make sure the surface appears lightly damp, with water into the crack...
3. Leave for 1h minimum, inspect; if crack is closing, repeat with slightly less water, and watch over next hour. As the crack starts to nearly close up, use Weldbond wood glue. Dilute by 25% with water. Mix well and add a small amount of semi-gloss or satin finish acrylic paint - Vallejo water-based acrylics are available online or at local modelling and art shops. EXCELLENT paint! Mix into the glue to tint it. Can do similar for repairing Rosewoods by matching the grain color also in lieu of black. For Boxwood, leave clear. 
4. Once tint and/or glue mixed, apply using a toothpick or FINE finishing brush (or fine nubbed modelling tip that looks like a thin Q-tip) - insert along the crack, carefully allowing it to fill into the crack(s) with minimal extra outside the crack. 
5. Leave for 5-10 minutes, inspect and repeat fill as needed. Once left for another 5 minutes, use a very lightly dampened Q-tip to wick off the excess long the crack edges, making sure not to remove the glue/tint as you go - rolling along the crack is fine, or better lightly rub along edges. 
6. let sit for 30 minutes, then inspect. If done well, the crack will either be sealed up or VERY nearly so. Then take either a good silicone lube (Dow Corning makes a good one for glass frit seals, or a wood wax polish that is clear works also). Put on a MF (microfiber) cloth and apply over the dried crack area to re-polish it lightly. Should be as good - or nearly so - like new. Certainly you have halted THAT crack running. 

Over the years, I have repaired and stopped cracks that have happened, making the set basically fine again. Trickier with Ebony-based pieces, since these are hard and shrink if dried too quickly. Acclimate them as much as possible (3-5 days in a box with SOME air-venting, then place on board for 1-2 days and return to box for another 1-2 days or so); Any cracks repaired are fine, and your set should stay pretty much as is from then on. During very dry times, inspect regularly for new ones, but this should repair any major issues (out of warranty) and have your set flaws almost invisible with any flaws only seen under very close inspection! 

Hope this was useful - good chess to all!

Rookium...