Stiffen a pipe

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Stiffen a pipe

Author	Message
Massimiliano	M Massimiliano posted 3 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x oekmont - 2/19/2021 2:15:07 PM If you add plates to the marked plane on both sides of the structure, and bolt them every few inches the stiffness should improve quite much. if you only find shorter plates you might just cover the middle area around the thinnest section. Thank you!!!
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oekmont	oekmont posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	If you add plates to the marked plane on both sides of the structure, and bolt them every few inches the stiffness should improve quite much. if you only find shorter plates you might just cover the middle area around the thinnest section. Attachments 20210219_150803.jpg (74 views, 86.00 KB)
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Massimiliano	M Massimiliano posted 3 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Lester Populaire - 2/17/2021 8:18:49 AM the plates on the sides was exactly what i was referring to with the shear webs, which would be far superior to the proposed tube that is bolted on. Thank you, I can't imagine really what you mean. If you have any spare time, would you mind drawing on my picture your suggested idea?
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Hanaldo	Hanaldo posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh agree with Oekmont on all points. Hadnt really considered bolting anything - I am used to working with roll cages in race cars where bolt-in is far inferior to weld-in. It would be here too, but it wouldn't be so important. Properly designed plates (as Lester described) bolted on would work well.
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oekmont	oekmont posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	This extra beam is -like the structure itself- not made with mechanical expertise. There are several reasons why the beam will not change the stiffness as much as a similar amount of material used in a more ideal way.
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Lester Populaire	L Lester Populaire posted 3 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	the plates on the sides was exactly what i was referring to with the shear webs, which would be far superior to the proposed tube that is bolted on.
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Massimiliano	M Massimiliano posted 3 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	I contacted the guy who originally made it and he is suggesting this addition (highlighted in red) made out of ss and bolted to the existing structure. What do you think?
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Massimiliano	M Massimiliano posted 3 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x oekmont - 2/16/2021 4:18:40 PM If possible you might consider to add some plates to the sides, at least around the knot section in the middle. They would take the shear forces and would change the stiffness of the structure drastically. no need for welding, a few bolts would be enough. This could be doable too, thank you
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oekmont	oekmont posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	If possible you might consider to add some plates to the sides, at least around the knot section in the middle. They would take the shear forces and would change the stiffness of the structure drastically. no need for welding, a few bolts would be enough.
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Massimiliano	M Massimiliano posted 3 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 2/15/2021 11:32:47 PM Doesn't make a great deal of difference, the issue is still the geometry of the structure. It needs horizontal bracing or gussets. Really the big problem with it is the way they have placed bent tubes together, they're not using the tensile strength of the tubes very well. If that outer tube on the right had continued straight down rather than being bent back and joining to the middle tube at a horrendous angle, and then they had added a horizontal brace or gusset to connect them then they would be utilising the tensile strength of the tubes much better and it would have been far more rigid. As it is, the main tubes on the left are working in tension, and the other tubes are really doing more work in compression which is no good. The process for welding vs the process for structural bonding isn't hugely different, so I still feel like it would be close to the same amount of work for either method. If you can't disassemble the thing or remove the wiring, how are you going to prep it properly for adhesive? Much easier to prep a 50mm area on each tube for where the new tube will be welded on than to prep the entire tube in order to bond a new shell on. Totally agree on the bad design but unfortunately I bought it already made. The aluminum is powder coated, I read that mma bonds very well to powder coated so I thought to just do a proper cleaning. I will also analyze the points of welding, if no wiring could be affected by the heat that could be feasible. Thanks for everyone's usual kind advices!
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