I've done and are still doing tops like this one. This pictured island top is 5 feet wide by 10 feet long and is 1-7/8" thick. No biscuits, no dowels, no salt or sand. Just good cauls, a well thought out process for glue up, and high quality clamps...lots of them....and I use no pipe clamps unless it become necessary for me to make a 12 ft long clamp for larger projects.
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