Part 4! Now that everything is hooked up, time to (finally) start building the tank enclosure from scratch with a sheet of 14 gauge steel and way too many man hours.
I am pretty stoked about this project. I have never done a significantly large sheetmetal project. I got some tools on long term borrow from a friend that I am excited to use: Finger brake, Hole saws, and Dimple Dies. I plan to use all of them on this project.
Here is a quick note on electric sheetmetal shears. There are primarily only two different types. One is for thinner gauge and is more of a nibbler, the other design is set up more like a shear and can handle heavier gauge.
There many different brands of these and they all appear to be exactly the same. So just find the one with the best price and warranty and go with it.
Here is the thinner nibbler type model that can handle up to 18 gauge steel (in sheetmetal the higher the number the thinner it is)
Here is the heavier duty version similar to what I bought and it is straight up awesome. It can cut up to 14 gauge with ease.
What is a finger brake? It is a metal bending device that has removable ‘fingers’ that allow you to make multiple intersecting bends in a single piece of sheetmetal.
Finger brakes don’t let you do everything though. I did notice while doing this project that there were a couple of bends toward opposite directions I wanted to do but couldn’t because the work-piece just can’t be inserted in the brake that way. Make sure you plan in advance, sometimes you have to modify your design to accommodate for your tool’s capabilities.
In the below pic you can see I was able to do bends in multiple different directions but that is only because my flange was ~1.5″ and it fit inside of a little cutout in the hinge (you can see the gap on the far left side). There were some situations where I just couldn’t do it though.
TIP: LABEL YOUR PIECES! It is really easy to get screwed up on which piece is what and where it goes. Save yourself some frustration and label well.
In case you didn’t know about it, there is an AWESOME tool called a RivetNut or Nutsert tool. Basically it is a pop rivet gun for sheetmetal but the rivets it puts in are threaded so you can fasten sheetmetal together with bolts.
For each nutsert size there is a specific hole size and thickness tolerance. Be sure to read the specs before you start drilling holes.
Building the lid
The sides weren’t too bad, they had 2-3 bends each with the front side having 4 bends. The top however almost broke my brain. Each side had to fit around three roll cage tubes and had 3 bends. I had to go old school on it and start with some cardboard. Oh, and as a bonus the roll cage tubes were pretty close to symmetrical but not close enough to just flip the template over, so I had to make a template for each side.
TIP: TAKE A LOT OF NOTES on your template. It is really easy to forget what was a cut vs a bend and which way you were going to bend it. The X’s are a great way to mark your scraps so you know what is what once they are cut apart.
Next step is to bend up the sides! Using this sheetmetal bender was a lot of fun. I will have to come up with some more ‘things’ to build with it here soon.
Again, make sure you plan your bends in advance! This doesn’t have to be super official. My process was to stand in front of the bender and ‘bend’ the sheetmetal in my head to see if it would work and in what order I should do the bends in. Thoughts like “If I bend this side first then I won’t be able to fit the piece back in the bender to bend this other side, so I should bend the other side first”.
Let me pause here to state the fact that there are obviously large gaps between the tubes and my sheetmetal enclosure. I had to have them in order to physically maneuver the sheetmetal into place. I went through a bunch of iterations trying to figure out how to do it in the fewest pieces possible and the best I could come up with was 3 main pieces. My current plan (though I am not there yet) is to build some filler plates that bolt on around the edges and cover those gaps.
I didn’t take very good pics of it but in the pic above you can see where I used 1/2″ thick adhesive weatherstrip from Home Depot to fill the gap between the box and the floor. I had to double/triple it up in some spots where the floor dipped. It isn’t perfect, but the box plenty stout and sealed up around the bottom. I might figure out a way to improve it in the future but it is good enough for now.
I was able to relocate almost everything that I previously had in a storage tote in the back around this new enclosure (you can see the socket set to the left, and I stuffed some other tow straps and such behind the rear seat).
That should make it so I can reserve the tray space for a cooler and misc stuff when we are wheeling… or groceries… maybe some stuff from the mall? 😛
Honestly, I am a little burnt out with this fuel tank/storage project. It was satisfying to build, but was also a lot more work than I had anticipated. Now that it is functional I am likely just going to drive it for a while and try to make it to an offroading event here soon.
Next steps are to build my filler plates and put some dimple die holes around the top edge for strength and to give me a place to strap stuff. I will probably wait until the weather gets nice before I try to paint it.
Hope you learned something. Now YOU, go to your shop and work on something!!