Cafeteria Banquette Seating (booth Seats)

I was commissioned to build the banquette seating for a cafeteria in the newly remodeled free press building in downtown Detroit. The design came from an outside firm. If you look closely, you can see the track hanging from the ceiling. Those are original tracks that the newly printed newspapers ran along during production. You can't see it, but the lights that are attached to the frames have a glass panel attached with old newspapers printed on them. Very cool detail.
The employees here are very very spoiled. One day I came in and they had a DJ spinning tunes, they have fooseball tables, slushee machine, snack bar and gourmet coffee and espresso. Spoiled I say. Maybe my boss could take notes here!

Step 1: Make a Cut List and Rip Up the Parts Needed for Assembly.

Step one is to cut the parts needed. There are a total of 10 boxes. Each box is 48" wide with the exception of the corner boxes and the end boxes. The corner boxes are a bit wider and the end boxes a bit narrower. All boxes are built the same way though except the box that has the large round column. That one was built differently but we will go into detail on that one later.

The box height is only 12-1/2", add on 6" of firm padding and you have an excellent height for a booth seat.
The box parts are 3/4" plywood laminated with an identical part to make them 1-1/2" thick. All of the box parts are made this way except the sides, those are just single layers of 3/4" ply. I do not have a lot of pictures cutting up the plywood, just piles of cut parts. I used a track saw and a table saw for this task.

Step 2: Assemble the Seat Boxes and the Seating Panels

The frames go together with glue and screws.

I started with the fronts and backs of the seat boxes. Each front and back frames are built the same way. There is a top rail and a wider bottom rail connected by two supports as pictured. The fronts and backs are then attached to one another with supports on the top only.
Once the fronts and backs are married, I attached the side panels to complete the seat box frames.

Step 3: Cut and Assemble the Seat Decks

The seat panels are 3/4" plywood. This is what the upholsterer will glue the foam padding to.

These consist of 3 parts, the seat deck, the front and a narrow filler.
Something to note is fabrics thickness... You have to cut the seat decks about 3/16 less on each side. I only gave an eighth of an inch and I fought with the seats because of how tight the tolerances were. If it was only a seat or two in one row, the eighth inch would have been plenty. But I ran five seats in one row and five in the other. It was a very tight fit.

Step 4: Scribe That Pesky Column

First step is to on site to get/verify the measurements myself. Once that's done, I used a scrap of plywood to scribe the column. I then took that scrap of plywood back to the shop to transfer the dimension to the proper seat deck.
Once I found the center of the the column (with some cool geometry tricks) I was able to use a router with a circle guide to cut the seat deck.

If you do not know the diameter of a circle and only have acces to part of the column, you can figure out the diameter with three points of the column.
Take a look at the picture to see the detail. but basicly you will connect one point to another with a straight line, find the center of said line and lay a square on the line with the longer edge going 90 degrees to the line at the center. Then scribe that line. Do the same to the other connecting line and where they meet is the center of the column. You now know the diameter, based on the radius.

Step 5: Cut the Back Panels

The design calls for square steel tubing mounted to the wall in various angles and lengths. I just followed the blueprint for this and using a track saw cut each of the 18 panels. All of the panels are made with 3/4" MDF.

Step 6: Get Sample Approval for the Client

The client loved the sample so the rest of the seat decks and back panels were sent to the upholsterer.

Now I move on to a different project while I wait.

Step 7: Installation Day - Seat Boxes

Took a couple days to install these. I began by bringing the boxes and placing them where they belong. Studs were marked on the wall, and a chalk line was snapped level with the top of the seat boxes. The boxes were then shimmed, leveled and screwed to the wall and each other.

The floor was terribly wavy. So I had gaps everywhere, I used scraps screwed and glued to the inside of the seat boxes to give full support before removing the shims. You can see them in the pictures. They're basically hidden legs.

Step 8: Installation Day - Back Panels and Square Tubing

The back panels are just glued to the wall with construction adhesive, the steel tubing is attached with anchors.

Basically start at one end and work your way to the other. Not much more to say here so lots of pics.

Step 9: Installation Day - Seat Decks, Toe Kick and Touch-up

Each seat deck got a block screwed to the underside to stop it from sliding around. The block size matched the oppening on the seat frames. Then the seat decks were payed in place and then I sat down very hard on it to lock it in place.
All that's left is the toe kick after the seat decks are in place.
The toe kick is simply scribed to match the floor waviness. This is done by placing strips of 1/4" black MDF against the seat boxes and then using a scrap block with a pencil layed on top then slide the pencil block across the floor transferring the floor waviness to the toe kick. Then remove the toe kick and cut along the line, then re-attach the strips.