First you need to glue it. Aliphatic glue will be fine. Don't worry
about the food issue.
What do you think it was glued with to begin with?

Next the glue isn't drying near the edges, the wood is shrinking at the
edges faster than the center. So it pulls away from each other.
Don't leave it out in the rain.
Blocks are meant for wet, but not soaking use. Doweling it will help,
but glue the dowels.

Use mineral oil to protect the wood all around. The top will wear but
the sides will appreciate it. A single coating will do.

BTW someone mentioned that the blocks were originally made with frames.
Maybe some, but some of the professional versions I had seen 30 and 40
years ago where just big solid chunks of end grain glued together. No
frames.. Would love to have one of those monsters today...


Tim Zimmerman wrote:
My Martha Stewart Hardwood Chopping Block (with four rubber
feet) splits in two after we left it in the rain. Here's how it begins. Over
time, the glues near the edges dry up creating gaps along the edges,
much like pine cones splitting under heat. The chopping block then
begins to show signs of splitting which eventually breaks in half under
a heavy storm.

I drill and insert several wooden dowel pins up and down the block. I
then join both halves together. I use no glue or preserving oil because I
couldn't find any food-grade glues or oils. I can see that it's a matter
of time before it breaks again, but elsewhere. What is a practical way
to keep a chopping block from splitting?

Thanks