Aluminum Extrusion load bars

About to get my Alu Cab canopy picked up in a few days, I see they have their own load bars for the canopy but only 1 slot - Data Sheet:
https://acmedia.s3.amazonaws.com/wp-content/uploads/2019/03/07085152/LB-1450.pdf
Pretty much a 25/80 mm extrusion from 6063-T6 alloy

Any insight on being able to use commonly sold aluminum extrusions?
I found this 25/75 mm extrusion made of 6005A alloy
https://8020.net/25-2576.html

It has 3 slots vs 1, and Wikipedia says both alloys have a tensile strength of 190kpa


Some more nerd stats
https://www.makeitfrom.com/compare/6005A-AlSiMgA-3.3210-Aluminum/6063-T6-Aluminum
https://www.linkedin.com/pulse/6063-vs-6005-which-one-right-pittman-kung/

I just need to read how to convert this stuff to how much kg/lbs I can put on each alloy type
Most of the other properties are nearly identical, other difference is their shape, the Alu Cab ones are more squared off

 

I typically put my design info into this calculator.

https://8020.net/deflection-calculator

 

Thanks, I've seen that part of the site when I was looking at their extrusions

Just little confused if my setup would be 2 fixed ends or 2 supported ends - I'm thinking they are fixed? Not even sure what supported end would look like

300lb on a single load bar is 4mm deflection, doesn't seem bad, I'd obviously use at least 2 for a tent and 2 people, maybe 3

Edit - a 4 ft load bar looks like it only gets 2mm deflection evenly spread out - I'd have 6 inches overhang just to mount extra stuff if a tent was up (lights, awening, water tank etc)

 

You are correct it would be 2 fixed ends. The difference between fixed and supported is that you can imagine fixed as the end most surface will never move at all (like when it is bolted to another supporting member.

Supported you can imagine putting your beam on 2 roller stands, as it deflects downwards it will draw the material towards the center.

I hope this is clear enough and helpful.

 

Oh whoops, I just realized what your picture is saying. That is a situation where it is a supported beam and I would set the beam length as the distance between the supports.

I was orgionally thinking of this like a prinsu roofrack where the ends are bolted into the end

 

Unless it's bolted in a few places that offers resistance to bending, I'd consider it a supported end and not fixed.

That calculator is oversimplifying it, there are multiple end configurations, including pinned, which would be closer to a single bolt axis at the end.