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  #1  
Old February 11th, 2013, 22:16
dfarmxj dfarmxj is offline
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plating rear of frame vs. rear bumper

Would building a bumper that slides into the frame rails as far as it will fit strengthen the rear structure enough to negate the need to plate back there?

I am looking at plating at the moment, but I want bumpers as well, and it seems that a piece of rec tube inside of the frame will be much stronger than welding a piece of ⅛" steel to one side of the frame. I know doing both bumper and the plating will be stronger than one alone, but I'm trying to watch how much weight gets added to the vehicle.

I think I am going to get the hd offroad stiffeners, but I was a little disappointed that the rears don't cover the bottom of the rails. Maybe fabbing some for the rears from ⅛"3"3" angle won't be too difficult. What have you guys done to strengthen the back end on your vehicles?
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  #2  
Old February 12th, 2013, 09:42
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NCCherokee NCCherokee is offline
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plating rear of frame vs. rear bumper

I currently have a bumper with tube in the rails. I plan on the plating the rails, but did the bumper first becuse I needed secure recovery mounts and I had some cracks at the stock bumper points.
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Old February 12th, 2013, 12:58
G2WANIT G2WANIT is offline
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Re: plating rear of frame vs. rear bumper

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Originally Posted by NCCherokee View Post
... did the bumper first becuse I needed secure recovery mounts ...
I believe this is why most people do the slide in bumper mounts...

Now, I'm no engineer, but I don't see them strengthening the frame unless you drill holes in the uni-body and weld them in... I plan on plating the outside and underside of the rear frame with 10ga plate. I have seen people use angle back there, seems to work well also.
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Old February 12th, 2013, 13:04
foxwar71 foxwar71 is offline
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Re: plating rear of frame vs. rear bumper

When I first built my rear bumper with 2x4 mounts, it definitely stiffened up the back of the jeep alot more then before. I had less issues with the hatch opening and closing, even when flexing. Now the rear rails are plated on the sides and bottom and nothing moves around. Dont worry about the extra weight, I think all the 1/8 I used to plate from the leaf hangers back only weighed like 15lbs.
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  #5  
Old February 12th, 2013, 13:29
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NCCherokee NCCherokee is offline
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plating rear of frame vs. rear bumper

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Originally Posted by G2WANIT View Post
I believe this is why most people do the slide in bumper mounts...

Now, I'm no engineer, but I don't see them strengthening the frame unless you drill holes in the uni-body and weld them in... I plan on plating the outside and underside of the rear frame with 10ga plate. I have seen people use angle back there, seems to work well also.
Agreed. I'm considering drilling holes and burning them in. My bumper bots to the slide in brackets, so I can still take the bumper off if I need too.

Also, agreed with foxwar. Weight shouldn't be much of an issue. And I pretty much copied his rear bumper mounts. Check out his thread
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  #6  
Old February 12th, 2013, 21:29
dfarmxj dfarmxj is offline
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Re: plating rear of frame vs. rear bumper

Sorry I didn't specify about the bumper, I meant fitting the bumper in the frame as far as it will go and bolting it into the factory hitch mounting and probably a couple of extra bolts on the sides and bottom on the front end of the tubes that go into the frame.
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Old February 13th, 2013, 05:26
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NCCherokee NCCherokee is offline
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plating rear of frame vs. rear bumper

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Originally Posted by dfarmxj View Post
Sorry I didn't specify about the bumper, I meant fitting the bumper in the frame as far as it will go and bolting it into the factory hitch mounting and probably a couple of extra bolts on the sides and bottom on the front end of the tubes that go into the frame.
We are talking about that as well. Look at foxwar's thread, he did exactly that. I did as well. My frame inserts bolt in place using the 8 factory bumper mount bolts, then an additional 4 on each rail for the hitch mount points. I have a rigidco rear, so it also bolts using two more in the center, and two more under each tail light for the cut rear quarter protection. It also uses the hitch points, so the rail is basically sandwiched by the bumper mounts.









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  #8  
Old February 13th, 2013, 06:17
G2WANIT G2WANIT is offline
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Re: plating rear of frame vs. rear bumper

Don't take this the wrong way, I like what you have done there, and I've done something similar, but I don't think it adds much to strengthen the frame. What that does is give you one helluva strong bumper mount and recovery points - which is obviously a great thing to have!

If I'm not mistaken, all the bolts are in the bottom of the frame, with the exception of the eight at the bumper mount. I think if you had some bolts running through the sides of the frame, perhaps all the way through with crush sleeves, then it would strengthen the frame more. (Or cut holes in the bottom and sides of the frame and weld the frame to the tube.) As it is, the square tube inside will allow the frame to twist and flex around it - just not along the bottom plate. I believe that is why people suggest you plug weld stiffeners along with stitch welding the outsides.
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Old February 13th, 2013, 06:40
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plating rear of frame vs. rear bumper

Quote:
Originally Posted by G2WANIT View Post
Don't take this the wrong way, I like what you have done there, and I've done something similar, but I don't think it adds much to strengthen the frame. What that does is give you one helluva strong bumper mount and recovery points - which is obviously a great thing to have!

If I'm not mistaken, all the bolts are in the bottom of the frame, with the exception of the eight at the bumper mount. I think if you had some bolts running through the sides of the frame, perhaps all the way through with crush sleeves, then it would strengthen the frame more. (Or cut holes in the bottom and sides of the frame and weld the frame to the tube.) As it is, the square tube inside will allow the frame to twist and flex around it - just not along the bottom plate. I believe that is why people suggest you plug weld stiffeners along with stitch welding the outsides.
Agree completely, which is why I said I plan to plug weld it before I plate it. This is step one. OP asked which to do first. I would do this first (I did) and then plate. Little harder to weld it after you plate it.
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  #10  
Old February 13th, 2013, 06:56
G2WANIT G2WANIT is offline
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Re: plating rear of frame vs. rear bumper

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Originally Posted by NCCherokee View Post
Agree completely, which is why I said I plan to plug weld it before I plate it. This is step one. OP asked which to do first. I would do this first (I did) and then plate. Little harder to weld it after you plate it.
HAHA, totally missed that you originally said that!

I know you were being facetious but man, EVERYTHING is harder after you plate! I had to drill all those holes through my TNT stiffeners to mount their skidplate and I wanted to blow my brains out - not to mention all the hole saws I went through
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Old February 13th, 2013, 13:22
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NCCherokee NCCherokee is offline
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plating rear of frame vs. rear bumper

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Originally Posted by G2WANIT View Post
HAHA, totally missed that you originally said that!

I know you were being facetious but man, EVERYTHING is harder after you plate! I had to drill all those holes through my TNT stiffeners to mount their skidplate and I wanted to blow my brains out - not to mention all the hole saws I went through
Yeah, I have TNT stiffeners, only ones on the market when I got them. Had to drill all the plug holes. Wanted to kill myself. Also had to drill through for the RK 3 link crush sleeves. The front may be a pain with the track bar bracket. I'll probably cut them short and weld them to the bumper mounts up front..
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Old February 13th, 2013, 13:56
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TRCM TRCM is offline
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Re: plating rear of frame vs. rear bumper

Ok, kinda related....why is the drivers side insert tube always cut out so much ?

Is it for the gas filler neck or something ?
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  #13  
Old February 13th, 2013, 14:02
G2WANIT G2WANIT is offline
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Re: plating rear of frame vs. rear bumper

That is exactly what it is for. I've seen where people who have already plated the rear frame will cut it shorter, I wanted to get to that bolt hole farther up the frame so I had to cut the tube down. If you've raised your tank, then not a problem, you just have to cut/pound out the tunnel for the gas filler line.
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  #14  
Old February 13th, 2013, 15:27
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SteveMongr SteveMongr is offline
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Re: plating rear of frame vs. rear bumper

Add a gas skid
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