Douglas Fir Bench Top

I’d just glue 2 pieces together for a 24” x 4” top.

-- Bondo Gaposis

3.5” to 4” range for thickness in a soft wood top is great. For width, bigger is better. The fewer pieces you laminate the less gluing up, alignment, and flattening you have to do. If I could have gotten a single slab for my top I’d have grabbed it.

If the 12” spans don’t include the pith (center of the tree, which makes them much less stable) and you can manage them (can get tricky maneuvering a heavy slab across a jointer or through a planer), I’d use two pieces. If you really want 30” (nothing wrong with that) than use three 10” wide. If you’re worried about movement, you can cut them down further and alternate growth ring direction, but I’d keep them as wide as you can manage.

-- John

If ripped and glued so the top face of the bench is in effect
quarter-sawn there would be some advantage in stability
across the bench. The wood will move more evenly
and you may avoid the seasonal bulges and valleys that
can occur with flatsawn slabs.

I used 14 doug fir 2×4s for my workbench top, so far it has been working great for me.

-- Drew, Delaware