Bed Cage Design - Part 1 Goals
To briefly recap, I had decided that I wanted to carry two 37” spares and wanted to figure out a way to do so while keeping my F-1 BaK-Flip, Bac-Box (*contents) and Bedrug.
I wanted to be able to securely take with me the following items:
- 55 Cu Ft Nitrogen Tank, with Regulator and accessories
- Backpack ready to go with 2.5 liters of Water, First Aid, Compass, Light Sticks, Jackets (Fleece and Shell), Leatherman Multi-tool, Flashlight, Hat, emergency Blankets, misc survival goodies.
- Mexican Blanket, assort Towels, 2nd Windbreaker
- Fire Extinguisher
- Igloo Marine 48 Qt Cooler
- Pittsburgh 2 Ton Racing Jack
- Reliance 7 Gal Water Tank
- 5 Gal Gas Can
- Shovel
I also do not want anything permanently affecting the ability of the pickup bed to be used as a Pickup Bed.
Because the 36 Gal Gas Tank is located on the Left (Driver’s Side) of the truck, I placed the heavier items on the Right. The 37” BFG M/T KM-2 with Stock Wheel weighs about 103Lbs and the 7 Gal Water Jug is also very heavy.
Design
I originally considered building the structure out of aluminum Tubing and tried to draw it out, it just didn’t work real well, so I decided to make a model out of PVC. Well the amount of work to do that vs. building a stout version out of ABS was not that much more difficult, or so I thought at the time and I was curious if I could build it strong enough as a permanent solution.
After a couple hours designing in the bed of the truck with actual components I figured out that the cooler if properly supported could sit on top of the jack and just clear the (inside) top of the F-1. The Water Jug if placed between the F-1 Rails also just touched the top of the F-1. So I go to bed with this unfinished drawing continuing to process in my brain thru the sleepless night.
So many different ideas!
Spent 10 hours constructing the ABS frame the next day, required 2 trips to Home Depot for more parts.
Description, #, Unit, Ext.
coupling 2 0.74 1.48
Trap Adaptors 6 1.94 11.64
Sani-Tee 30 1.73 51.9
Test Tee 6 4.55 27.3
90 deg vent 14 1.39 19.46
ABS Cement 1 4.27 4.27
ss clamps 5 5 1.27 6.35
10' 1.5" ABS 6 5.59 33.54
Total 70 connectors and $155.94
They don’t make a 4 way connector so you have to get creative.
The Test Tee’s are a 3 way connector where the middle part has a screw in, instead of glued. This allows the Trap Adaptor to screw in. I used these on the sides to adjust left to right to compress the cage once it is installed.
I used a Cardboard template of the 37” tire since my spare is currently a 35”, this ended up being a mistake as my template somehow came out to large which required a reconfiguration. This easily added 2 hours of work and another trip to the store. I did end up strengthening the design at this point by adding more up and down connections.
I had planned all along to pull one of my 37” tires off to calculate height of the cage as I wanted the top of the cage to equal the height of the tire. Well that is when I discovered my error. The take-away here is to have all your items there in your bed when you do the design.
Lifting a 103 Tire is somewhat awkward, especially if you don’t want to wear road dirt. Dropping the tire in at an angle to use the least amount of bed space is not worth breaking the cage or your back. I want to be able to easily slide out the tire onto the tailgate, so I gave up some space on the right. So be it. By doing this it turns out I didn’t have room to mount the Nitrogen Tank on the left side of the Cooler/Jack set up, so be it, in the Bak-Box it stays.
I not only drew the design on paper, I used 2” Blue tape to mask it off in the bed. This made it easier as I built the design.
Construction:
The hard part about doing this out of ABS is that the Sani-Tee 3 Way connector is “Y” shaped where one side is longer than the other as it relates to the middle.
The tip is to always have the connector pointing in one way when going L to R and the same thing going Front to Back.
For some strange reason, I decided to construct the top section first. If I were to do this again I would start on the bottom. I also delayed too far into the project putting the actual tire where I wanted it. Had I done this earlier I could have pre-cut all the uprights that would make the upper section easier.
The entire middle section of the upright portion mirrors the bottom section. So when cutting a piece from the top cut a matching piece for the bottom. Same thing on cross pieces, make sure they are exactly the same size. I used my compound miter saw, but any chop saw will do. By matching these sizes exactly it will make for an easier glue up.
Completely assemble your creation and make sure you are satisfied before gluing. It is possible to make changes, but depending on where it can be problematic.
Gluing
ABS Cement dries in less than 10 seconds, and is permanent in about 30 Seconds. Have a rubber mallet near by in case you make a mistake.
I took out sections and glued on flat surface.
Don’t glue any of the uprights until the very end. The goal is to have a complete Top and a separate complete bottom section glued up individually, then dry fit it once more before gluing together. I did the final assembly upside down so that the glue would not run out of the fittings as I attached the uprights to the bottom section first.
Be strategic when deciding what pieces to glue together, look for the longer straight pieces and make sure all the connectors line up by eyeballing it after each connector. Then connect the longer straight sections together as complete units. Be careful to not invert the 3 ways. It gets confusing because you often are working upside down and inverted, so easy on the booze. If you make a mistake just salvage what you can and chuck the rest.
I was fortunate I only wasted 2 connectors and had estimated the number of long tubes the first time correctly.
Keep in mind getting the unit in and out. I did not glue in the back pieces so it can collapse some to get in past the side rails.
I was happy with the result, had my doubts if I was going to get it done before I lost daylight and energy to complete. I am challenge driven and this “Thing” was definitely challenging. It is super strong, and I can jump up and down on the core part, I would guess it could support over a 1000 pounds of evenly dispersed weight in the supported sections.
