How are you attaching the border wood?
The long sides on the thicker boards (1-1/8”) made from Camphor Laurel and Cedar were biscuited and glued with Titebond 3. The ends on these boards I’ve again used the Titebond 3. 
The Silky Oak and Hardwood boards are only 3/4” thick so I’ve just used the Titebond 3. 
All the boards were sanded down to 320grit before the polishing. 

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