Another Rear Bumper Fab Thread

[mason10198]

Got the main step plate in! Unfortunately had to cut it as two halves because my CNC isn't big enough to cut the whole thing. Put 2 massive gussets under each "half" (post a pic of those later). Should be getting more done this weekend... It almost looks like a bumper now!

[bartonmd]

Looks like a good start!

Mike

[mason10198]

Decisions on hinge design... This is what I have to work with: https://goo.gl/cfDf9p
I had originally planned on cutting off the bottom "tab" of the bracket and welding it into the bumper where it is sitting here-

realbracket

-and then drilling a hole in the bumper (what i'm calling the "step plate") for the hinge bolt to go through where the bottom tab of the bracket would have been, and then welding the nut inside the bumper, on the underside of the step plate.
On paper, that would look like this from the top-

idea1sketch

-and when chucked into the Fusion model, looks like this-

idea1model

BUT with a little more thinking, I think it might be better to essentially forget that bracket, and just fully incorporate one into the bumper itself. Which would be almost exactly the same as what I just showed above, except 'pushed' towards the passenger side, into the 'box' that the step plate wall and passenger wing come together to make. Which, on paper, looks like this-

idea2sketch

-and wait, what do you know... I'm so ignorant i didn't realize thats exactly what Mike did right here, just with heims instead of a bought hinge-

mikeissmarterthanme

SO, when I modify that idea a little bit to work with my big phat hinge instead of heim links, I get this-

betteridea

-which I think will be a way better option both functionally and aesthetically.

[HARDTRAILZ]

I searched a good while on the rear bumper and gave Mike a ton of ideas. I really liked the heim for adjustability if needed at all and it did prove to work well.

I need to get the swings back on my truck, but been wanting to redo the jerry can mount side with a platform that could hold either a couple jerry cans of a cooler or similar. Something a bit more useful since I really dont need to haul fuel around constantly

[mason10198]

I wanna go the RotoPax route as far as fuel storage. Everyone knows it's dumb expensive, but it is super convenient to be able to switch sizes and have water cans/dry storage that work with the mounts.

[mason10198]

After a little more work in Fusion:
GIFs are so much fun...

[Trail X]

Looks good, just don't forget to draw in your welds. I think you're going to run into your welds on full open. It'd make sense to also have some space between the between the arm and the step plate. Normally you want it to at least ride on a washer or two so you're not scraping your arm across the step plate.

[mason10198]

Yes, I still have to raise everything up a fraction or two to get it to fit, I just hadn't done that in the model yet. Working on that part and the radius today hopefully

[mason10198]

Mostly finished with the hinge side. Nasty welds until the gap fill on the sides of the radius. Underside hasn't been welded yet either, gotta go refill my bottles. Those random looking plates on the bottom of the mounting arms are just spacers to help line up the 90 degree on the angle fit up in the rounded corners of the frame rail, so didnt spend much time measuring or cutting those. Just kinda threw them in there and welded them on.

[ETB1]

Looks good, can’t wait to see it finished. I have to cut mine out piece by piece and weld together, only have a plasma cutter, grinder and a welder lol

[Trail X]

Good looking welds!

[mason10198]

Update time! Phew, it's been a short while. Lets see...
I've build most of the arm, tire mount, and passenger side of the main bumper. I added some more structure to the hinge side to minimize deflection when in the open position. I took a plasma cutter to an old front hub assembly for use as a tire mounting plate, which was full of grease and probably gave me cancer. After plasma, I ground the backside of it down relatively flat and welded it to a *45 on the end of some 2x2 to form the stick out angle. I had a piece of scrap laying on the ground from a hole saw that just so happened to fit perfectly in the center of the hub, so I used it to fill in the CV shaft hole and seal it all off. Did some more measuring and chopping until I came up with a good mounting stand and welded it to the arm. There is plenty of room for the back glass to open with the arm closed (new 35" tire shown), probably enough room for a 37".

Sidenote as I sit here looking at my welds... I am by no means a welder. My dad taught, er... told, me how to half-moon a puddle with a 110V/90A FCAW when I was 13, and I've been self/youtube taught ever since. I built my front MDB kit winch bumper with the same 90A machine. I just recently upgraded to a nicer 240V/220A multiprocess machine, this bumper being the first project I've used it on. With that said, I've been MIG'in this thing together with little to no clue what I'm doing. Sometimes I lay down pretty beads, sometimes I try to wipe it off because I'm so convinced it came out of the backside of a bird with the flu. Just throwing that in there for anyone looking through the pics trying to contain their laughter

Geez, can we get back on track now???

I had planned on using the Rotopax system for fuel/water storage since it's fairly modular and robust. I have since decided against Rotopax for a few reasons. Everything about them is stupid expensive for what they can hold. A plastic 2gal Rotopax can costs just as much as a brand name steel 5.3gal NATO Wavian jerrycan. The best I could do with Rotopax is (2x) side-by-side stacks of (2x) 2gal cans totaling my aux fuel storage at 8gal, and that would cost an upwards of $500+. I can easily use (2x) 5.3gal NATO cans totaling almost 11gal.

BUT I have to either find some type of NATO mounting bracket online that I can use, or make my own. I'd really love to put one of THESE on each side of the tire mount "pillar" like this...

...but I'm not sure. Please let me know if anyone has suggestions for this.

Onto the pictures. Uploading here sucks, but uploading to a third party risks broken pics when someone comes to look at this thread later on. So if you're reading this in 2019 or later, you're welcome for the next few hours I'll spend attaching these one by one...

[ETB1]

Looks good brother. I personally like the jerry can idea. That is why i chose to do the dual swing arms. Jerry cans are cheaper and in my opinion will last longer. Though i may be partial being from military background and all.

[Trail X]

My jerry can holder seems to work pretty well. Granted, my old holder bracket rusted out (the one pictured here), but the single ratchet strap concept works really well. Just needs some oiling from time to time.

[mason10198]

I made a quick sheet metal copy of these mounts in Fusion, should be pretty easy to bam these out of some... lets say 14 gauge... on the plasma and bend them up. A couple of small hinges and padlockable draw latches from McMaster will cover hardware. Then I'm thinking I'll put some adhesive neoprene foam in there to keep it from rattling. Eh?

[mason10198]

These will fit back behind the tire perfectly!

bumper.gif (3.9 MiB) Viewed 28368 times

[Trail X]

Those look good too! I like the little gifs Mason. Pretty sweet!

I always try to keep the cap accessable, because I use a siphon. Much easier to siphon from where its mounted than to pick one of those things and try to pour them in your tank.

Also, the gas cans are rather thin. They hold up for a while, but I'd recommend putting some rubber or something under them. Mine finally rusted through (I think where the mounting screws were rubbing) on the bottom and started leaking gas.

[mason10198]

I always try to keep the cap accessible, because I use a siphon. Much easier to siphon from where its mounted than to pick one of those things and try to pour them in your tank.

I thought about the cap being accessible as well, but as easy as it will be to just pop the latch and get the 'strap' out of the way, it wasn't worth designing around that idea. I did go ahead and move the crosspiece back towards the handles, where it can help hold the can down better. I'm not sure why 4x4innovations has that piece there, I assume just to help keep the lid from opening on its own?

Also, the gas cans are rather thin. They hold up for a while, but I'd recommend putting some rubber or something under them. Mine finally rusted through (I think where the mounting screws were rubbing) on the bottom and started leaking gas.

Yeah, good idea. I'm going to get some of this rubber sheet and put it in between the can and the holder in a few places like under the crosspiece and on the bottom. Also just to help with rattling.

I ordered some cute little weatherproof Master locks for the draw latches to keep the bad guys at bay too.

[mason10198]

Dropped it off at the powdercoat shop today. Didn't end up making the fuel can mounts, I will make a bolt on version of those later. Right now I just want to get this thing coated and on the truck.

[Flyingfischer5]

Nice, Can't wait to see it.