# Which is better for structural support PVC pipe or plywood?

#### AamsterC2

So the support structure is the "T" in your sketch? And the load is the brown hanging part?
That is correct or that's how I thought it should be made. Do you have an idea for a better way to do it?

#### berkeman

Mentor
That is correct or that's how I thought it should be made. Do you have an idea for a better way to do it?
Triangles are usually better than "T"s. What kind of bracing can you add at the right angle joins? Evem better.can you design it as a triangle support or a rectangular support?

#### AamsterC2

You mean something like this?

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#### AamsterC2

Oh wait OK let me totally rephrase this. Under a bending stress which can sustain more stress an equilateral triangle, a square, or a circle assuming the height of the triangle, side length of the square and the diameter of the circle are all the same value. I think this is what I should have been asking from the beginning

#### berkeman

Mentor
Oh wait OK let me totally rephrase this. Under a bending stress which can sustain more stress an equilateral triangle, a square, or a circle assuming the height of the triangle, side length of the square and the diameter of the circle are all the same value. I think this is what I should have been asking from the beginning
Bending which way? Can you upload a 3-D perspective drawing of what you are wanting to do?

#### AamsterC2

Just a weight placed right in the middle like if there's a tube, a box beam and a hollow triangular structure each a meter long with the same wall thickness, held at either end and each with a force pressing down on the center. Which could withstand the most force?

Edit: And so sorry, I can't upload a 3D image

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#### Nidum

Gold Member
Best support for that kind of structure is a pair of shaped plywood cuttings with spacers between .

Shaped how?

#### AamsterC2

oh so an anvil shape but would it hold out with 3m on either side and all the weight?

#### Nidum

Gold Member
I see that you have added some new dimensional information to one of your posts since I first read it .

To have cantilevered platforms as long as 3 metres on a narrow central support pillar is not a realistic proposition .

Possibilities :

Use three or more support pillars with metal bracing at intermediate and end locations .

Use multiple trestle leg supports under the whole lengths of the platforms - probably much easier for you anyway .

#### AamsterC2

Ok hmm I suppose I could try making support for the ends that could be placed after the wings

#### Nidum

Gold Member
Can you fix the construction to a wall ?

#### AamsterC2

No, I was planning on it to be mobile

#### the professor

KISS IS THE EQUATION- you can build a bow -archery type- out of pvc -good luck with plywood.

#### Dr.D

What I'm making is a long wing like structure for display, it will be about 10ft (3m) long and I'd like it to last a long time.
I'd be very reluctant to build anything from PVC if I wanted it to last a long time. PVC is a plastic type material and deforms plastically with the passage of time. Plywood has some of the same problems, but to a much lesser degree in most situations.

"Which is better for structural support PVC pipe or plywood?"

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