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Vince Shriver
01-18-2017, 8:54 AM
I'm making a grid to support a workbench table, using solid maple 2" x 3". The field of the grid will consist of 12 half lap joints and be dadoed & lag bolted into a frame of the same material. My question: do I glue these lap joints together and/or shoot them with a 15g nailer? All the grain runs the same direction. Thanks for any thoughts. Vince

Lee Schierer
01-18-2017, 9:04 AM
Gluing them will give you a stronger joint.

Jim Becker
01-18-2017, 10:29 AM
Glue is what makes the joinery strong. Any fasteners are for alignment and a little more strength. If you want to either shoot some 15 gage nails or use screws, there's no harm other than them being visible unless you plug and sand. Personally, I'd use screws for extra reinforcement, but nailing is faster.

Prashun Patel
01-18-2017, 10:59 AM
What does 'grain runs in the same direction' mean? The half lap grids are by definition, cross-grain, right?

At the risk of answering the question not asked: is this an assembly-style table or a workbench?

If it's an assembly table where flatness is key, I'd think you'd benefit by having a thinner, taller lattice, say 1x4. If this is a workbench that must resist racking forces when planed, or might benefit from dog holes, then a sparser grid of thicker members might serve better?

I could be totally off, but I just don't see a good deal of 2x3 tops supported by 2x3 torsion boxes. Just asking here, not judging.

Vince Shriver
01-18-2017, 11:58 AM
The material is from an old workbench top that will be more useful than when stacked up in a pile. It will be an outfeed table for the table saw and general purpose bench. I guess I mis-spoke regarding the grain direction, but to clear up what I meant: I cut a long 2 x 3 piece of the top into several shorter pieces for the cross members. So even though they will be perpendicular at the lap joint, the grain in both parts remains horizontal - unlike, say, a bread board end. I thought that any movement of the two parts would be in the same direction. I'm probably just over thinking this stuff. Thanks.

lowell holmes
01-18-2017, 12:50 PM
Just glue it. You could peg the joint with a wooden dowel for aesthetic purposes.