Custom Bed Rack: Need Some Help With Sizing

I am beginning to mock up some plans for a custom bed rack to have fabbed up nearby and am looking around on multiple other forums as well as here to gain some knowledge. I like the design of the All-Pro pack rack and will be modelling mine somewhat similar to it. All pro says they use 1 3/4 DOM tubing with their rack, but what i dont know is what wall the tubing is. I was thinking about choosing 1-1/2 OD x .095 wall x 1.310 ID sized tubing for the build. What i do not know is that if this is overkill or not. For camping now i will have a roof basket on top of the rack and a RTT will be hopefully replacing the basket in the future. That is the best i can give for a weight guestimate here, basically whatever the RTT weighs and about 315 pound of people body weight.

I guess what i need to know here is could i get by with 1-1/2 OD x .095 wall x 1.310 ID? Or could i go even lighter and try for 1-1/2 OD x .083 wall x 1.334 ID? Going to the smaller wall pipe also cuts the price down! Just not really sure what im looking at here.

 

I'm by no means an expert in this area, but my gf and I built a bed rack for her truck with the structure being 1" x 1" square tube .080" wall.
It has done its job supporting the weight or her RTT and both of us in it.

(Inspired by Box Rocket's bed racks - https://www.tacomaworld.com/threads/box-rocket-fab-bed-racks.251952/ )

 

Oh damn, so then 0.85 wall round should do the job then? If it can support the RTT with a hi lift and shovel on it i will be satsified. Is square stronger then round? I read square is better if you are worried about the metal bending.

I found this design and kinda just fell in love sooo

 

I'm no expert, can't say if .085 round will be as strong or stronger than .080 square.

That one looks good! I dig it

 

Well your mentioning of square tubing has given me some ideas, it is also MUCH cheaper to buy square tubing. I am thinking i will now attempt this out of 1-3/4 x 1-3/4 x 14GA (0.83) square steel tubing. Thanks to your help with the info from your rack build as well as box rockets AND the crazy one from ttora I got a decent idea of what to do here now.

 

Measure three times, cut once haha. Sub'd for pics

Our end result: