Beginning the rear bumper build; may need some help... (1 Viewer)

[FullyLitLED]

So I bought a bumper from Mike at Bumpitoffroad.com! However, rather than ordering the swingouts from him, I will be fabbing my swingouts from scratch. I posted this in the 100 series section but there isn't much DIY in that forum in terms of building bumpers or anything else for that matter haha

Plans include removable bike carrier integrated into the tire carrier and the other swingout will be a ladder of some sort or some kind of utility to carry a gas container. I drew up a rough sketch of what I want, I was lazy to draw the actual bumper shell so I used a fellow mudder's pic(Brock) and cropped out the top. The picture is not to scale obviously but it gives me a rough idea of the layout.

Since I will be adding an excessive amount of weight, I will be going with comp4x4's heavy duty spindle, rated at 1800 lbs(compared to the standard 1250 lb rating). As for the latches and other locking components will be rated at more than 3000lbs so that the bumper will be overbuilt

I am not sure what to do about the second swingout yet but for the first swingout, I decided on a tire carrier with a basket on top of it. Adjustable to the offsets of wheels and width of tires of course.

I am aware that a lot of the "members" or sqare tubing that I installed will end up being zero force members but they have a function since they will aid me in keeping the tire carrier ridgid when I am putting it together or adding excessive strength. Also, in order to minimize the buckling, I decided to weld in 3/8" triangle braces at corners where it is critical to brace the carrier. I want the top basket to have mesh and a locking lid so I can leave the lid open and out a small cooler there or my recovery gear.

Derlin landing pads will be installed at the point where the carriers will lock closed in order to minimize vibration which will cause undue stress to the swing arms.

Here is the rough sketch(front view)..drawing it in CAD soon as I get time. Bumper is arriving tomorrow and spindles will arrive friday so its time to get to work!
Any comments or concerns to help improve the design will help! Thanks in advance guys!

 

[ardentyota]

I would suggest making the basket removable. That's a lot of weight and if you're not using it all the time, why carry it?

The short arm could be built for a Jerry can and Hi-lift. Might even be able to put a cooler basket on top.

Examples

 

[Slowerthanu]

IMHO, after building quite a few tire carriers, you are overbuilding that.

I am not sure what you intend to carry in the basket, but you are adding a considerable amount of weight in structure alone.

I agree with making the basket removable. I would also consider building it on the other swing out and having steps integrated into it for accessing the roof, kill two birds with one stone and move the weight to the passenger side for balance. It also would allow you to mount the basket lower, keeping the COG down and making it more accessible

What wall thickness and tubing size will you run?

On my FJ40, I used 2x2 .188 wall to mount my 37 on a single swingout, screw down latch and cutting board material to rest on.

My FJ62 uses 2x3 .120 on a dual swingout. I rest it on cutting board material and use De-Staco clamps. The clamps I used are too small (700 pounds) and I plan to upgrade them. I have not fully finished this setup yet though as I am waiting on a 1 inch die for my bender.

 

[MANUCHAO]

This is what I did with my 4+ rear bumper... I modded the swing outs and can be used differently depending on the type of trip..

Here is the thread if you want to see how I have changed it during the last few years....

Im thinking of adapting a bike carrier to the pass swing out but still havent come up with anything yet...

https://forum.ih8mud.com/60-series-wagons/384009-i-mod-my-rear-bumper-tad-bit.html

 

[FullyLitLED]

Good points by both of you! The basket is for recovery straps and d-shackles and other hi lift components. I wanted to have them up and out of the way. I was going to put it on the ladder that I have planned and have them so that I can swing them out of the way so accessing the ladder will be easy.

As far as the swingarm I will be going with 2"x3" square tubing. For the ladder and sub frame of the tire carrier, will using 2"x2" be viable and save a lot of weight? Or should the whole thing just be 2"x3"? I plan on using square tubing for the ladder as well because I am scared of working on the round tubing right now!

 

[FullyLitLED]

Ordered these up, should get interesting next week as I cut some metal up...any ladder building tips would be appreciated...

Tire Carrier Hinge Kit - Heavy Duty - 1-3/4" Mega Spindle



I see that 4x4 labs has a two piece outer frame assembly, is there a reason for that?

 

[FullyLitLED]

bumper got expensive because I bought a sawzall, impact wrench, drill and grinder...

anyways, I have a bit of a dilemma, the spindles that I bought are 2-3/8" in diameter, but the holes that came with the bumper are already cut out at 1-7/8", what can I use to enlarge the hole to 2-3/8"? I can't use the hole saw because there will be no place for a pilot hole

edit: had an idea

can I cut a piece of thick wood, fasten it to the metal somehow(with the proper hole size cut out in the wood) then use that as a template for the new larger hole? Theoretically sounds good but I am not 100% sure, it may be bad!


good securing method for when the carriers are closed
http://www.expeditionportal.com/for...r-hinge-idea-help?highlight=rear+tire+carrier

 

[spressomon]

Plasma cutter.

 

[FullyLitLED]

Plasma cutter.

I do not have one of those, but will ask around

 

[chill will]

Go to Home Depot or any hardware store and ask for a step bit. It's a drill bit in the shape of a cone that progressively bores the hole until you get to your specific diameter.

 

[chill will]

Oh yeah it's much cheaper than a plasma cutter looking at under $20.00

 

[handcannon]

bumper got expensive because I bought a sawzall, impact wrench, drill and grinder...

anyways, I have a bit of a dilemma, the spindles that I bought are 2-3/8" in diameter, but the holes that came with the bumper are already cut out at 1-7/8", what can I use to enlarge the hole to 2-3/8"? I can't use the hole saw because there will be no place for a pilot hole

edit: had an idea

can I cut a piece of thick wood, fasten it to the metal somehow(with the proper hole size cut out in the wood) then use that as a template for the new larger hole? Theoretically sounds good but I am not 100% sure, it may be bad!


good securing method for when the carriers are closed
Spare tire carrier hinge idea/help

Yes--The block will work. I've done that numerous times when needing to enlarge holes in cabinets and entertainment centers during modifications. The thickness needed will be just 1/4 to 1/2 inch.

Don

 

[ardentyota]

Go to Home Depot or any hardware store and ask for a step bit. It's a drill bit in the shape of a cone that progressively bores the hole until you get to your specific diameter.

I've never seen a step bit in 2 3/8" diameter.

 

[MANUCHAO]

X2..on the step bit.
Did not know they make them that big..
Plasma cutter.. Easy peasy

 

[chill will]

Yup my bad largest they come is 1 3/8

 

[spressomon]

Leo...another way to enlarge the hole is to use a die grinder (air or electric)...they're certainly less expensive than plasma cutters!

 

[davegonz]

Ordered these up, should get interesting next week as I cut some metal up...any ladder building tips would be appreciated...

Tire Carrier Hinge Kit - Heavy Duty - 1-3/4" Mega Spindle



I see that 4x4 labs has a two piece outer frame assembly, is there a reason for that?

Did you end up buying that spindle you mentioned earlier in the thread? Looking at the link, it looks like it comes with a sleeve that you weld on unlike other designs that make you weld the spindle onto the bumper. I think you can skip the sleeve and just weld the spindle to the bumper. That might make it easier with your hole problem.

 

[bhmmapping]

tack weld a piece of scrap metal across the bottom of the hole to give you something to pilot the hole saw.

 

[FullyLitLED]

Did you end up buying that spindle you mentioned earlier in the thread? Looking at the link, it looks like it comes with a sleeve that you weld on unlike other designs that make you weld the spindle onto the bumper. I think you can skip the sleeve and just weld the spindle to the bumper. That might make it easier with your hole problem.

Dave, I did get that spindle and sleeve was included, I was going to add the sleeve in order to minimize the chances of snapping the spindle in half, since welding the spindle sometimes has harsh effects on spindle strength

tack weld a piece of scrap metal across the bottom of the hole to give you something to pilot the hole saw.

Good suggestion, if my way fails I will try this method!

 

[FullyLitLED]

How are my welds? Sleeve welded to bumper, spindle tacked onto the sleeve