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Very simple tire rack holder? With drawing.

  1. Jun 23, 2010 #1
    I found this forum by accident and am learning stuff i never thought i wanted to know. Im getting ready to build a spare tire holder for my off road landcruiser.

    The metal will be 2" square tubing. The weight it will be holding is a 100 pound rim and tire...

    Here is a rough picture. Any recommendations on how thick the metal should be? The hitch i believe is a class 2.

    Very rough pic. Now, im going to be doing hard 4 wheeling with this setup. So i need to make sure its not going to sheer off. Any tips on metal thickness??
     

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  2. jcsd
  3. Jun 23, 2010 #2
    31 views, no response. Am i missing info for you guys to give an educated guess on what i should use???? Thanks for taking your time.
     
  4. Jun 24, 2010 #3

    Ranger Mike

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    i do not like a cantilever design with zero lateral supports. too long an arm susseptible to vibration and stress but if you are going to use this design use a minimum of .125" wall thickness steel tubing.i would go thicker if you can afford it..add gussets to the 90 degree angle to reinforce. do not rely on bolts..weld it and gusset..the wheel mount plate should be at least 1/4 steel, 3/8 is better , use three wheel lugs to spread the load..
     
  5. Jun 24, 2010 #4
    Like Mike said, there's a lot of vibration fatigue that could eventually crack the aluminum, or more likely cause the bolt holes to start looking like ovals, then it cracks. I'd recommend bolting, with Loc Tite, a gusset or two to brace the angle if Mike agrees. I'd use 7-8 inches on a side. Now your weak point might be the pinned hole where it inserts into the hitch.

    And, by the way, that trailer hitch hole isn't a perfect square it has a radius at the corners. You will have to knock-down the edges of anything you insert, giving you thin spots.
     
    Last edited: Jun 24, 2010
  6. Jun 24, 2010 #5
    Ok, here is a new design i will try.... Hows this look. I will use 3/16 metal tubing. Its only 20 bucks more.. the design is under the picture... let me know.

    Ok looking at the back of the bumper you have these 4 holes. Those 4holes is where you can bolt and aftermarket hitch to it.. I will make a tab that comes off the arm that i can bolt into the bumper while in transit... Then when i need to lower the back, just unbolt and pull the in and it will lay down to open the back... Here is a picture of the back bumper bolt holes. This is what i will bolt the tire holder to.
    attachment.php?attachmentid=429489&stc=1&d=1277090183.jpg
     

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  7. Jun 24, 2010 #6

    Ranger Mike

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    excellent..i like the gusset to the tire/wheel mount plate..grade 8 bolts are ok..no need for grade 10 bolts..save some $$
    the sumbch should last ferever!!

    good job!
     
  8. Jun 24, 2010 #7
    Mike, im going to have the pivot at where it bolts to the bumper. Any recommendations how to make a pivot to where it would lay down flat??? Im stumped there..
     
  9. Jun 24, 2010 #8

    Ranger Mike

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    you want to be able to quickly remove a pin and have the spare tire rack fold down so you may easily load something into the rear storage area..right?
    instead of the bottom gusset ( hitch lateral bar to vertical post) drill a 1/2 inch ( or larger) hole through the post and use this as the pivot. ( may require notching the vertical post. next we need to replace the bumper bolts with studs. I would use wing nuts to secure the vertical post. finally i would drill a small hole through this stud and use a hitch pin ( looks like a big hair pin) to keep the wing nit from coming loose...
     
  10. Jun 24, 2010 #9
    Ok, added a few more modifications...

    What should i make the pivot out of??? I added something for the tire to lay back on. Here ya go.
     

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  11. Jun 24, 2010 #10

    Ranger Mike

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    the side straps should be at least 1/4 inch thick mild steel. the weak point will be 1/2 inch pivot bolt but will take years to wear out...in this case size does matter so over build it and it will last..when you are building this..tack weld the pieces and test fit everything..
    make sure everything clears.. once a final design is completed then you weld the assembly
     
  12. Jun 24, 2010 #11
    Side straps= the tabs that the bolts on the bumper go through? What grade should the 1/2 pivot bolt be?

    So that appears like it will work pretty good then???
     
  13. Jun 24, 2010 #12

    Ranger Mike

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    yes side straps are what the pivot bolt goes thru..grade 8 is good enough..i would try this design
     
  14. Jun 24, 2010 #13
    Ok, final drawing.... Look good?

    The pivot plate obv. mounts on the pivot arm... missing anything.?
     

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  15. Jun 25, 2010 #14

    Ranger Mike

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    add top and bottom and side gussets to plate number 6
     
  16. Jun 25, 2010 #15
    Mike. After going over the design. It dawned on me, the whole reason im moving the spare tire from under the truck is clearance. Well now i will have a hitch that hangs out about 8-10 inches or so.. I will be blasting that thing every time i go over some decent size rocks with it hanging out.. SOOO, im going to try two more designs to run by you that will leave that area free and move the tire carrier up...

    Here is my first one. Drawing the second one now.
    So, i will have grade 10 bolts holding it in, 1/4 plate mounting to bumper. The carrier needs to fold down... Any ideas on how to do that??? I will put the second one up in a few mins.
     

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  17. Jun 25, 2010 #16
    Ok, here is the second one.. I like this one. The spindle is a big beefy trailer spindle. 2k or 4k pounds. That goes through the bumper which has a plate under it. Then that can just pull out of the way.. When its resting it will be a tight fit and i will have it on a solid rubber bushing with a latch to hold it in place and a pin also...

    Thoughts??
     

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  18. Jun 25, 2010 #17

    Ranger Mike

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    now that is one class act.....smokey yunick would be proud!!!
     
  19. Jun 25, 2010 #18
    LOL, i dont know what that means. ahaha Is that good? Bad?? Talk to me Mike. ahaha.
     
  20. Jun 25, 2010 #19
    Ok, i looked up Smokey and he seems to be a pretty cool dude. So would you change anything on the final pivot? Any ideas.
     
  21. Jun 26, 2010 #20

    Ranger Mike

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    no ..your design looks solid and i think you got a winner!!
    let us know how it turns out!
    rm
     
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