Module System

As discussed in a previous post, connecting these modules (corner, cupholder, player station) to the base was going to be a challenge. Because wood moves throughout the year as humidity changes, you can’t just glue things together willy-nilly: if you join two pieces of wood together at a 90° angle, they’ll end up cracking at some point because the forces are opposing each other and something has to give.

As I was designing the table I came up with what I think is a pretty good system for attaching these modules, and even allows me to change them out in the future. My solution was to drill holes through the base and use threaded inserts in the modules:

These are M6 threads and accept M6-1.0 x 30mm flat head bolts. Now I can simply bolt the modules to the base!

The tricky part was going to be making sure that the holes line up between the base and the modules. To do that, I made a couple of jigs with drill bushings that make sure the bit stays at 90° to the surface I’m drilling. I drilled them both out on the drill press using a fence and stops to be sure I cut the holes in the same place on both jigs (each hole is 1 1/4” in from the ends):

On the modules, I used a 7/16” bit to start a hole which would let me counter-sink the threaded inserts. Then I went to the drill press and drilled a 11/32” hole centered on the first, which actually accepts the threaded insert:

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The corner modules have 4 inserts total:

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Then I used the sister jig to drill 1/4” holes in the base:

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Four bolts and the corner module is connected! The bolts aren’t currently countersunk, but I’m debating whether or not I should…the edges of the bolts are chamfered so you wouldn’t bang your knee into it or anything, but it might look a little cleaner if you were to peek underneath.

The length of both sides of the table are multiples of 6” (84” x 54”) and each module is as well (corners and cupholders are 6” wide, the player station is 30”). As long as I stick to modules that are increments of 6” I can swap them in and out and the holes in the base will accept them! I’m already wondering about replacing one of the 2 cupholders on each short end of the table with a dice tower…

Update

I’m thinking of increasing the holes in the base from 1/4” to 5/16”. This would give the bolts just a little bit of wiggle room in case a module ends up 1/32” over or undersized (not uncommon when working with wood!). I’ll pound out the bushing inserts in the jig, drill a bigger hole, and put in new inserts.