Aluminum Gauges?

[carringb]

Albina Pipe in Tualatin does tube bending, including AL.

https://www.albinaco.com/bending-profiles/pipe-and-tube

As for sizing, it all depends on your loading, support system, grade AL, and welding skill. 1/8" 6061 is common, probably strong enough, but doesn't have much mass so it'll be hard to keep a puddle going without burning through. Might want to go up a bit just to make welding easier, since at 1" O.D. the weight difference is negligible. If you want large diameter tubing, then going thinner will net bigger weight saving.

[northleftcoast]

I’m out on the coast west of Portland and would be happy to help you bend up the hoops of a rack. Typically if you are bending an Alumimum rack similar to what you see large manufacturers producing, 1” schedule 40 6063 is your best bet. Bends easily and is strong. I like 1x1.5 6061 rectangular cross bars for stiffness. I also bend racks and raft frame hoops out of 1 1/4” schedule 40 6063. Wall thickness for both is about .133” ish.

1” pipe gets you about 1.3 ish OD
1.25 pipe goes over 1.5” OD.

You will double the cost of your materials and the weight of your rack if you start decking it with 3” bar slats or perf sheet.

Check the specs at Alaskan copper and brass for exact data.

If you can weld and cope you can build a rack for a small fraction of what the big box outfits charge.

PM me for details if you’d like to collaborate.

Sam

[pjtpj]

I've been through this exact process and here are my findings:

• You can use Finite Element Analysis (FEA) to accurately model the weight bearing capacity of your design. We use Fusion 360 and I believe free trials are available. There is a learning curve. As a side benefit, you will have a 3D CAD model to work from.
• Fabricators aren't excited about new AL tube bending projects. Usually, they bend steel, they don't really understand the math, and they may not have the necessary bending dies, so working with new materials and diameters is challenging. Eventually, I figured out the math and learned that I can get all the bend parameters I need from a single bend and even use the "test" piece in my project, so it isn't really that mysterious or expensive. The bender and die you need will cost about $2k - I have a 1" bender and die down here in Ventura if you want to use it!
• For a rack made of tubing and bar, you are going to want to use TIG welding. If you don't already know how, you are going to have to put in 100 or more hours of practice in to get good enough to weld something that will still require grinding and painting to look nice. With another 100 or so hours, you can "stack dimes" and get a weld that might not require grinding to look good.
• You can save a lot of money (50% or more) on the raw aluminum by buying in bulk through a distributor.

[northleftcoast]

Here are the specs from Alaskan Copper and Brass:

Pipe for outside rack hoop and any tube that needs to have a bent radius:

6063-T52 Schedule 40
1” pipe OD 1.315, Wall .133
1 1/4” pipe OD 1.660 Wall .140

Straight length pipe that should not be bent. Stiffer than 6063:

6061 - T6 Schedule 40
Specs same as 6063

Good cross bars for stiffness:

6061 - T6 rectangular tubing
1”x1.5” .125 wall

Typical slats for decking with 16” to 18” OC crossbars, spaced 1” to 3” depending on budget and aesthetic requirements:

6061 - T6 Rectangular Bar
3” x 3/16”

.125 3003 Perforated sheet can also be sourced for about the same cost as the slats.

[northleftcoast]

And Pipe Aligners.........


3/4” pipe just fits inside 1” pipe, so it is nice to use a short ~3” piece tucked inside any pipe butt joint. You can buy commercially made aligners that have knurling in the center which makes them work a little better than smooth pieces. If you have a lathe, Knurl a 1/2” circumference at the aligner’s midpoint. Otherwise, tack it to one side of the joint, fit the piece to length, clamp, and weld it up.