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Post by 8 inches longer, again on Nov 25, 2012 17:09:05 GMT -4
Scott, those are TJ 44's...not for JK. G2 doesn't have a bolt in JK 44.
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The Garagemahal
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Post by The Garagemahal on Nov 26, 2012 9:12:30 GMT -4
Ah crap !! Thought I read JK and Tj axle assemblies
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baddog
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Post by baddog on Dec 4, 2012 13:46:01 GMT -4
So being the geek that I am, I ran some strength checks on the D44 housing The basic process is this: 1) measure up the basic geomtery (dimensions & thicknesses) 2) create a simplified loading diagram 3) estimate what load would need to be applied to a stock axle to cause it to yield (permanent bend) 4) compare internal sleeves to ProRock44 (PR44) 5) look for a cheap/easy way to get the same strength. Loading diagram: There are a few things that jumped right out: A) It takes a static load of about 4000lbs on each wheel to bend a stock axle (D30/D44). NB: The GVW of a pimped out JK is around 5500lbs. B) Axles almost always fail at or near the pumpkin, usually on the longer passenger side. This is due to the discontinuity caused by the increase in diameter when the axle tubes socket into the pumkin. C) Weld-in sleeves vs pounding one in makes no difference if it can transfer bending moment to the pumpkin. Neither one can unless it is welded at the pumpkin end. D) Stock axle deflects about 0.5" at the mid point at its elastic limit so axle shaft clearance is an issue. E) 1/4" sleeve in a stock axle is about 80% as strong as a PR44 IF it is welded at the pumpkin. F) 1/4" sleeve stuffed in a stock axle is about 50% as strong as one welded at the pumpkin due to the absence of any moment transfer to the pumpkin. G) A 1/4" sleeve stuffed in a stock axle makes no appreciable difference on the drivers side tube as the local deflections are too small to load the sleeve. H) Adding a 3/8" thick x 1.5" wide doubler on the outside of the tube, top & bttm is twice as strong as stock and stronger than a PR44. I'm thinking that C-gussets, Lower Control Arm skids & the doubler plates would make a stock D44 pretty darn tough. Certainly enough for anything I am going to see.
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Post by 53m38 on Dec 4, 2012 20:11:34 GMT -4
What do you mean by doubler?
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baddog
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Post by baddog on Dec 4, 2012 20:55:19 GMT -4
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Post by 53m38 on Dec 4, 2012 23:16:34 GMT -4
Is the doubler square tubing?
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dan
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Post by dan on Dec 5, 2012 6:23:02 GMT -4
looks like a piece of round tube cliced open, and welded around the tube? thus "doubling" the wall thickness, and making it much stronger due to the welds along the length of the tube, rather than just one end or the other?
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baddog
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Post by baddog on Dec 5, 2012 7:00:05 GMT -4
exactly ... its just an extra thickness of material.
the big differences between an external doubler and a sleeve are: - doubler is more effective (further from centre of tube) - doubler is just where its needed (top & bttm of tube) - doubler is 100% effective as it is welded all around - doubler does not reduce internal clearances
Unfortunately, the doubler can't be the full length of the tube without cutting off brackets.
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Post by SocialWheeler on Dec 8, 2012 1:00:32 GMT -4
So when people build axles from the tubes out why do they not all put in full length doublers and weld the brackets to that?
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justajeep
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Post by justajeep on Dec 8, 2012 8:45:19 GMT -4
All the axles I've built have been Dana 44's and they had 2.75 OD tube with a 3/8" wall. I can't get 2.75 x 3/8 without special ordering it, so I use 3" x 1/2" and turn down the ends. It's plenty strong enough.
The gussets on the knuckles is a good idea, but other than that I really don't see the need for anything else, unless you plan on jumping it it a lot. I don't know of any of us that run hard rock trails that have ever bent an axle, even Dana 30's.
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Creepy
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Post by Creepy on Dec 8, 2012 8:53:11 GMT -4
Sorta agreed, but consider JK D30's are a few inches wider, and the JK's are heavier. Not a straight comparision. And he's comparing to other options, rather than a stock axle. it seems the 'clam-shell' satisfies his design parameters better than the other options, even if it is a bit overkill.
I wouldn't worry too much about the brackets having to come off, if you were going that far anyway, you might as well beef the tracbar and LCA mounts at the same time.
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Post by 53m38 on Dec 8, 2012 11:18:35 GMT -4
Plus, isn't the wall thickness thinner on the JK axles then previous?
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baddog
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Post by baddog on Mar 10, 2013 9:28:14 GMT -4
Well the axle situation is problematic.
- OEM Dana 44 front is on back-order until forever.
- Rubicon front end from a wrecker is harder to get than an honest politician
I'm trying to work up something with Andre at APJ ... stand-by.
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baddog
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Post by baddog on Mar 10, 2013 9:43:25 GMT -4
Now that I'm back home, I have been puttering away. ;D Back on page 12 of this never-ending saga, I thought I could graft the OEM flares back onto the Poison Spyder flares to help with the on-road spray control a bit. The main goal was to come up with a strong attachment that I could put on / take off very quickly. After much experimenting, here's what I settled on: Two aluminum supports clamped onto the fender braces: Using seriously thick nut plates: The assembly looks like this: The OEM flare is narrowed up a bit to match the Poison Spyder outside line (sort-of): Aluminum angles connect the OEM flare to the supports: A tricky bit was making the clip fro the front edge: All done it looks like this: Gotta figure out the fronts now ....
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Post by 8 inches longer, again on Mar 12, 2013 23:19:03 GMT -4
Neat idea John, seems to work well. Is this something you had been planning all along or did you get hassled by the fuzz on tire coverage?
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