Creating LEGO-based furniture seems to be a right of passage for all parents. Here's mine. Oversized sidewalls contain the LEGO on the table during dumping. A custom mountain with LEGO baseplates encourages building scenes and racing vehicles down the slope. Finally, when it's time to clean up, pull up the manhole cover and sweep all the LEGO into the integrated container.
Step 1: Table and Sidewalls
The table was $20 at a used furniture shop. The sidewalls are leftover chair rail from a home renovation project. The chair rail is cut at a 45 degree angle and attached with glue and screws from below.
The sidewalls are high enough that with only a modicum of caution, it's possible to dump the plastic bin full of LEGO on the table without losing pieces. But, they're not too high that they interfere with play.
Step 2: Cut a Hole in the Table
I traced a circle of approximately 4 inches and cut a hole in the table with a jigsaw.
Step 3: Integrated Shelf
The integrated shelf is designed to hold a plastic bin. It is glued and screwed in place.
I retrospect, I wish I had made the shelf a little bit taller. There isn't enough space for the plastic bin's cover.
Step 4: CNC Cut Manhole Cover
Despite effectively cutting the table's hole freehand, I opted to CNC cut the manhole cover. When you've got an Othermill, everything looks like an Othermill problem...
I designed and created the cover's toolpath in Fusion. The part is here and a Fusion file is attached. I had some plywood of an appropriate thickness, so only needed a pocket operation. The .NC file is also attached, but since it's specific to the Othermill and my thickness of plywood, it's probably best for general rather than specific inspection. Othermachine has a fantastic tutorial on using Fusion with the Othermill.
Step 5: Build Mountain
I asked my 6-year-old what features she wanted on the table, and she chose a mountain.
I cut and screwed together a few pieces of plywood and 2x4s to make an approximately 60 degree slope mountain that fit between the sidewalls and to one side of the hole. We then painted it.
Initially, I had planned to attached it rigidly to the table, but am glad I didn't because the moveable mountain can be used off of the table to extend the play surface, it can clear away to make more space on the table, and it can be used with other playsets, particular our wooden railroad tracks.
Step 6: Paint
We painted with indoor, semigloss latex paint.
Step 8: When Done, Sweep All Those Parts Into the Bin!
When you've found the missing piece, sweep all the remaining LEGO into the bin!
Step 9: Play!
In this particular scene, apparently all the bad guys are riding the helicopter and 8-wheeled vehicle. They are "going to the movie theater where they're going to eat all the popcorn!"