make a Prius rear sleeping bed platform for two, step-by-step walk thru

Enclosed is a step-by-step walk thru to build a 6 foot 4 inch flat cargo area that would facilitate a 2 person sleep area. The rear cargo area (behind the drivers seat) has a length of about 5 foot 3 inches. The desire would be to extend this length by a foot or so to allow 2x standard backpacking mats side-by-side to accommodate a flat sleep area within the Prius. The goal of the build includes:
1. Design and fabrication of a sturdy, stable platform.
2. Can be build with common materials and tools.
3. The platforms can be stowed (when not in use) within the under-floor hatch, out of sight.
4. Can be set-up without too much hassle or time.
5. As a secondary consideration, is adoptable for the 2010 Toyota RAV4 (V6) also. The RAV4 has about the same cargo area of the Prius.

The annotation describing each figure will occur at the bottom of the picture.

View of prius cargo area with back seat folded down


5 foot 2 inch (flat distance) distance from rear of cargo to folded back seat rest


1 foot 5 inch excess distance for platform. Just need to consider design options that meet the criteria listed above.


Camping mat at 6 foot long 20 inches wide


another compact inflatable backpacking mat


20 inches wide with added pillow sleeve. add clothing between mat and sleeve to make a pillow


mat in cargo area of prius


overhang needing support, about 1 foot

support platform .5 inch laminate oak from Home depot


Mark a 22 inch x 15 inch section


quick fit, will need to mount here


.125 inch thick by 2 inch wide Aluminum strap, from Home Depot


Mark for trim 4 inch length's 3x total parts


Cut with band saw, fine tooth blade



round sharp corners

deburr parts

use this tool to determine mounting fastener grip length


fasteners from Home Depot


diameter of threaded shank at .1845


Drill slightly larger than fastener shank at .186 inch


set-up for drilling holes


drill holes, 2x holes per part, .5 inch from edge of platform


using flush manufactured head fasteners, need countersink in straps


use this piloted countersink tool bit, 100 degree


machined straps completed


close-up of fastener installed


deburr drill exit side


mount straps on platform


quick fit check in prius, A-ok.....


add a 4 inch angle to the middle strap, the extended flange will fit between the rear seatback and the head rest, stabilizing the fore-aft movement of the platform


drill


mount like this

Now for the front platform attachment, I'll use the passenger headrest as the attach point

strap kit items


100% nylon thread, 3/4 inch buckles and 3/4 inch nylon straps


stitch the part like this, one hard attached female buckle, one threaded female buckle, one adjustable male buckle.


melt the ends of the strap with a soldering iron


like this gives the polished look


hand sew the end of the female buckle to the nylon strap


finished product, repeat 3x more times total


length ~9 inches


strap slots in the platform to thread in the 3/4 nylon strap, use router bit from dremal tool


hard attach the nylon strap at ~18 inches, add male adjustable buckle


finished product, now for mounting


1. Remove the rear shoulder restraints, it's ok they re-attach easy, shift fwd seats all the way fwd and backrest fwd.


2. fold rear seats down


3. Attach the headrest buckles


4. mount the platforms, attach the headrest buckles, adjust front strap length till level


rear view


about 6ft 4 inches of total usable length


add floor and/or rear cargo mats over the joint as an option


backpacking mats inlayed


View from front seat


view from outside


with cargo cover, for some privacy


gap between mat top and cargo cover


inside view


RAV4 rear with seats down


5 ft 4 inches from rear to top of folded rear backrest


platform installed, no modifications to platform by the way, just so happens to fit


view of the angle added to stabilize the fore-aft movement, same as prius


both platforms installed


rear view


mats in RAV4


front side view of mats on platform


view from passenger seat


platform ready to go under cargo storage area of RAV4


fits well in RAV4, no issues


Prius storage, no issues

My intent is to keep one platform in the Prius and one in the RAV4 for emergency usage and transfer one to the other car for a long distance road trip.

 

That would work for a planned trip. The platform in the thread is now in the cargo under stowage floor. It can be used in a pinch when needed. I also keep the mat and sleeping bag. You never know......