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  #16  
Old January 10th, 2018, 21:02
trippled trippled is offline
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Re: Rear inner stiffeners

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It sets up a condition called "stress concentration," but, do as you please.
This. Sharp corners=stress risers. It's why you should round corners off of things like mounting plate.
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  #17  
Old January 11th, 2018, 06:28
burntkat burntkat is offline
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Re: Rear inner stiffeners

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It sets up a condition called "stress concentration," but, do as you please.
I seriously doubt that's a concern after you've melted the corners into puddles mingled with the base metal, and the welds are surrounded by large amounts of undisturbed steel
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-94 ZJ: Budget boost, 31s. The wife's DD.
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  #18  
Old January 11th, 2018, 14:18
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Re: Rear inner stiffeners

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Originally Posted by burntkat View Post
I seriously doubt that's a concern after you've melted the corners into puddles mingled with the base metal, and the welds are surrounded by large amounts of undisturbed steel
Your probably right. However, square holes in a rosette weld application is about as dumb as it gets. There's a reason why you don't see square windows on an airplane. Unfortunately it took many of them to fall to the ground for engineers to see the problem.
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  #19  
Old January 11th, 2018, 16:24
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Re: Rear inner stiffeners

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Originally Posted by Boostwerks.com View Post
Your probably right. However, square holes in a rosette weld application is about as dumb as it gets. There's a reason why you don't see square windows on an airplane. Unfortunately it took many of them to fall to the ground for engineers to see the problem.
or square doors/hatches on a ship (not talking about non-structural doors).........it's a lot easier for a crack to propagate from a corner than from a side....which is what a rounded off corner is
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  #20  
Old January 11th, 2018, 17:21
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Re: Rear inner stiffeners

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I seriously doubt that's a concern after you've melted the corners into puddles mingled with the base metal, and the welds are surrounded by large amounts of undisturbed steel
And I'll never see the cracks in the base metal, from my house.

Like I said, do as you please.
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  #21  
Old January 12th, 2018, 05:52
burntkat burntkat is offline
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Re: Rear inner stiffeners

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Your probably right. However, square holes in a rosette weld application is about as dumb as it gets. There's a reason why you don't see square windows on an airplane. Unfortunately it took many of them to fall to the ground for engineers to see the problem.
Definitely agree on those points! Although internal pressure isn't really the issue here.
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  #22  
Old January 12th, 2018, 07:39
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Re: Rear inner stiffeners

Haha. Interesting points. I was going with round holes because I figured it would be easier while making my little circle motions. Lol

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  #23  
Old January 12th, 2018, 09:24
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Re: Rear inner stiffeners

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Originally Posted by burntkat View Post
Definitely agree on those points! Although internal pressure isn't really the issue here.
Internal pressure wasn't the problem. An airplane (or any well engineered structure) is designed to twist and deform without concentrating stress into any one point. This is exactly how cracks form.

http://en.wikipedia.org/wiki/De_Havilland_Comet
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  #24  
Old January 16th, 2018, 23:18
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Re: Rear inner stiffeners

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Haha. Interesting points. I was going with round holes because I figured it would be easier while making my little circle motions. Lol

M
Hmm, we have ships and airplanes, why not trains??? I might have seen some cracks in some steel, a time or two...

I used to work in the rail industry, so, I tend to copy approved practice for railcar repair. Notice the call-outs for a radius on the transitions.

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  #25  
Old January 17th, 2018, 13:26
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Re: Rear inner stiffeners

Options
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  #26  
Old January 17th, 2018, 14:33
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Re: Rear inner stiffeners

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I would have grabbed a set if these for the outer side but already have some installed. They just don't wrap under.

I see people make them for the front now that wrap under. I need to do the front soon and have plates. Wonder if it's worth selling and getting some that wrap under in the first place.

I plan to and if it's a good fit and saves me time I would be all for it
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  #27  
Old January 17th, 2018, 14:35
burntkat burntkat is offline
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Re: Rear inner stiffeners

The bottom looks pretty straightforward, IIRC (I am not in the XJ today). I would think it would be easy to template it with cardboard, a hammer, and some snips. Trace it onto plate and weld it in.
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-89 S-10: SAS, D44s front/rear. 5.7L V8. 700R4 with 4L60E upgrades. Built in my driveway.
-90 XJ 4.0, AW4, 231J: Clayton's longarms, RE 5.5" coils, hybrid 6" leaf pack, 33/12.50/15" MTs, Rancho 99012s and 99624s, Tera HD SYE, custom sliders, BW flares. Rehabbing with D44s, RE spring packs, RE 4.5" coils, and ACOS.
-94 ZJ: Budget boost, 31s. The wife's DD.
-97 XJ: Son's DD. 4" lift, ACOS, 4" spring pack, Upcountry coils, 31s
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  #28  
Old January 17th, 2018, 18:58
Heavyopp Heavyopp is offline
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Re: Rear inner stiffeners

$54 shipping for the stiffeners in the second post to NJ

That's having them made in 3/16 plate

I don't know about the rest of you but adding 30% to the cost for shipping makes me want to fab them myself
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  #29  
Old January 17th, 2018, 19:34
trippled trippled is offline
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Re: Rear inner stiffeners

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$54 shipping for the stiffeners in the second post to NJ

That's having them made in 3/16 plate

I don't know about the rest of you but adding 30% to the cost for shipping makes me want to fab them myself
I built my mid and rears out of 3x3x3/16 angle iron. It's a time consuming job but it works well. They're a little short (don't go as close to the floor as I'd like) in rear section but oh well.
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  #30  
Old January 17th, 2018, 20:29
Heavyopp Heavyopp is offline
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Re: Rear inner stiffeners

I just had to drop my fuel tank today -- Fuel pump went ---- Saw that previous owner cut a 4" rectangular hole in the frame rail above the nutsert -- guess they had problems securing the trailer hitch

Anyway -- I will weld in a plate while the tank is out -- These inner stiffeners would be perfect but shipping costs are ridiculous -- I'd rather spend the money on a full sheet of 3/16 steel and make my own
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