what do you all think

 

I think you need to beef up the hinge area.

 

how so

 

Well, from what I can see in the pics, it appears that you have a small platform that is holding the hinge in place. I don't know what the bottom of the hinge itself is attached to (the side of the bumper?), but that small platform will have a tremendous amount of twist on it from the weight of the tire, and the carrier itself. If you look at some of the other tire carriers around, they have the top of the hinge mount and the bottom of the hinge mount braced. What I'm saying is that you need to "over-build" what you are working on to ensure that it will not fail. When I designed my rear tire carrier, I made sure that the mounting point of the hinge was welded at the top and bottom of the mounting section.

This is just my opinion, not facts or anything set it stone.

 

the platform is 1/4" welded to the bumper, and the hinge is a 1" grade 8 bolt welded to the under side of the platform. it's plenty burly

 

I know stevo is not trying to sound like a smartass. He actually is right. If you check out other people who have built tire carriers, they stress the importance of making the hinges very very strong. I think bamachem has a thread on how he built a tire carrier. Nonetheless, great work!

Off topic: where in MD are you located?

 

i know he's not being a smartass, i looked into buying a spindle from 4x4 labs, but i couldn't shell out $120 for it. i figured if those are stout enough, then a bolt with a sheer point of 15,000 pounds would be. i've already stood on it and it holds me. a top hinge is not possible on the trucks or i would have done that.

 

looks good i really like it! Soon here we are gonna be building a custom rear bumper for my runner and this is a realy cool add-on we can do to it. Cant wait to see the final product.

 

okay....

well, good luck. I suggest welding an eyelet to the tire carrier, as well as one to the bumper and secureing the tire carrier to the bumper with some strong steel cable. This will help you aviod a lawsuit in the event that the tire carrier breaks off on the highway, preventing it from injuring or even killing someone else.

 

what kind of eyelet are you talking about, and how do you figure it's gonna break off, if it will support me(170 lbs) it will support one 60 lb tire and wheel.

in your infinite wisdom where would it break?

 

frederick MD

 

well the tire is going to see a lot more force than you just standing on it. No need to get defensive, they are just trying to help you out.

Do it your way, and if/when it fails, you will know what to fix. Did you also fab up your rear bumper?

 

http://www.sonoransteel.com/rearbumper.html
Read down to steves update near the bottom.
you need to make the hinge double shear at minimum. lost of peolpe have had the hinge snap off inc one on the highway.

 

what do you mean by double sheer?

that sucks though, mine sits on the platforms so there isn't any weight on the hinge unless it's out.

 

where it is capured by both bottom and top, with a tab or something. where it slides between 2 mounting points.
an example of double shear: (it is a shock, i know but thats the general idea)

 

i'm not gonna post up and say indirectly that somthing someone just put several hours of work into is 100% guaranteed to fail, it's rude. i don't see how a 1" grade 8 bolt is just gonna break with very little weight applied to it, in regards to its sheer weight. i don't doubt that over time the bolt will wear, and become weak. but the way i built this, it will be easy to just replace it before anything happens.

or i could be completely wrong.

i don't see how a 65lb tire and wheel and maybe a 5gal gas can applies more force than me swinging on it. but if i'm missing something about this i'd like to know.

the way i see it, the 4x4 labs HD spindle will hold 7500lbs, the 1" grade 8 bolt will hold more, the platform- i tested it with the hi-lift. so i just don't get where my tire carrier is so weak or sucks so bad, it's disappointing really, i thought i did a semi good job.

 

oh, i did that.

 

you need (must) devise a better retainer for when it's closed. that pin simply is not safe. you should probably have a cam-locking latch like what is used on 99% of all commercially-built rear bumpers that have tire carriers. they're not cheap. mine was about $70 for a 2000# stainless version from mcmaster-carr, but it's worth it.

also, i personally don't think that the bolt will break, but it could eventually tear that little 1/4" thick ledge from the face of the bumper.

however, the weakest link are the two 3/4" pipes that you expect to hold a 65# tire.

the problem with using small stuff is that it ever-so-slightly bends and returns (vibrates) during every day driving. this bending eventually weakens the metal (fatigue) and it will give out.

 

The problem with you design is NOT the static loading (weight of the tire and carrier on the Grade 8 bolt) it is the dynamic loading (weight of the tire and carrier bouncing up and down at multiple times the static loading in all different directions) that will bust your pin. FWIW, I do have the experience and education to evaluate it as such as I work professionally as a fabrication engineer...and I have never stayed at a Holiday Inn Express.

If you don't want folks to offer constructive criticism in the future, you might think about not posting your efforts on the internet, as your exact words to begin the thread were

"what do you all think"?

so folks have told you honestly and tactfully it seems. I do not see anyone saying it "sucks" or your efforts were in vain, just in need of some supplemental improvements.

I'd beef up/brace the hinge, latch and the tire mounts for sure. There are a lot more loadings other that just dead weight that you must compensate for with bracing and such. You do NOT want that tire carrier or parts thereof frolicking down the highway towards other vehicles.

Good luck.

 

I 2nd and 3rd and 4th this..................