Started this project this weekend. Phase I is complete, and I'm pretty happy with the results. This post is to give back to the community. I read a bunch of posts before I started on this to see how others had done it. Just adding my experience to the pool of knowledge.

Props to @Centerpunch --his thread for his project was my primary source: https://www.northamericanmotoring.co...partments.html

A rear seat was absolutely worthless to me. Only two humans live in my house, along with one 120# Malamute named Yogi. Yogi loves to ride, but needs a bigger platform.

After removing the seat and installing dynamat in the floor, I built my front platform using 1/2" OSB, a 2x4, and 30" piano hinge.

No videos, but the details:

2x4 is for front edge, cut to approximately 42". I test-fit so that I had about 1/2" to the trim panel on each side. I drilled 2 1.5" holes to allow the 2x4 to fit over the seat brackets along the front edge. When the board fit properly, I noticed that it "rockered" front to rear, and then discovered that there are 4 bolt ends that stick up on the leading edge (you see the location of two indicated in the photo below by the holes with the circle inscribed around them). I drilled the locations of the holes to allow the board to sit perfectly flat on the leading edge of the seat well. I also spent some time with my sander rounding all the corners and edges of the 2x4 so that I minimized the risk of splinters and sharp edges that might cut carpet later once I cover the platform).

2x4 for leading edge of seat delete panel

I cut the OSB 42" wide to begin with (sorry, but I don't remember the front-to-rear dimension, you'll want to tailor this to your install). I then tapered the sides to match the contour of the car side panels. This turned out to be pretty easy. From the front edge, I marked the width of the 2x4 that I had already prepared. The back edge needed to be 35" wide where it attaches to the "rail" in the floor, so I marked 3.5" in from each side on the back edge, and cut a line to the mark on the front edge. Hard to describe, but the resulting cut OSB board is 42" wide from the leading edge back 3.5" (width of 2x4), then tapers symmetrically from that point back to 35" wide on the rear edge. I did a little finish work with my sander to clearance all interior panels by 1/4-1/2" (to allow carpet to wrap board, and not put significant pressure on side panels). I also used the sander to work all edges and corners.

I chose piano hinge instead of door or gate hinges. Can't give you a compelling explanation for why I chose it, but I like the way it finished. I attached with small hex-head sheet metal screws to the top edge of the "rail" in the floor.

Close up of hinge install. Hinge design allows for hex head sheet metal screws, wood screws are countersunk.

Panel installed, in open position

Final install of panel


I don't think I'm going to install any type of latch to hold the front edge down. There is no slop or bounce. The floor carpet eliminates any vibration noise. I'm going to run for a week or so like this to make sure I don't want to adjust anything, then will cover with a pad and a good automotive carpet.

I am still contemplating how I will build the rear platform section. I had originally planned to hinge it, but don't like the way the interior panels limit the opening height/angle. Centerpunch's method appears to give plenty of clearance to get to the battery compartment, but I'm also considering making it free-standing. I need something stronger to support the rear edge than the hasps he used, because of the weight mine needs to carry. I'm considering installing feet on the bottom of the rear edge of the panel, if I decide to hinge it, and on all four corners if I make it free-standing (would need to use a bungee system to keep it in place if I make it free-standing).

Pretty happy with the progress so far. I'll update when I resolve the rear panel dilemma, and as I learn anything new.

 

Good job!

 

I'll be doing very much the same thing with Marine plywood, same hinge material (Stainless steel).

Mike

 

Just realized that I never updated this thread with the rear panel install!

To refresh-I need the panel to be able to handle a 120# dog riding on it, so the design needs to be sturdy.

After much contemplation, I wound up with a hinged back panel using another piano hinge on the body rib, and two legs in the back to support the rear edge. (I also forgot to take in-progress pictures).


Final install of the decking. I drove around like this for a few months to test before I installed the carpet. Many dog-laden miles, including one camping trip, and it has held up great!

Rear panel detail-piano hinge attached on body rib. Rear legs are from a Home Depot shelving unit. I installed threaded nut inserts into the decking, then used a large washer and long bolt to attach the feet. I set the spacing wide to minimize the intrusion in the cargo space. I have a small plastic toolbox that is the right height for the space that fits between the feet, providing additional support.

Finished install from rear. I decided against black carpet. It's hot, shows Malamute hair, and was kinda boring. I found some Hyper Blue Carpet! I'm planning to change out my dash panels eventually to match the body color Carpet is a continuous piece from front to rear, with a continuous piece of pad beneath it. It's glued down everywhere except about 1" directly above each hinge, allowing for flex when the panels are opened.

Finished install from the front.

 

Wonderful job on the rear seat delete, and the carpet color is perfect.

Please post a few photos of Yogi riding in the new space in your Mini !