Bending tube tech

[OverlandZJ]

I'm looking at trying my luck at some fab work, and have a design in mind for what i want to accomplish. However i dont have the skills, yet.

My question pertains to bending radius, how do i determine it so i can purchase the correct die? My local Steel supply facility cannot bend the material i plan to use... which is 3/4" square structural steel.

I found this manual bender in a search which lists a 3" radius.

http://www.irvansmith.com/scart/tubing-bender-manual-p-659.html

I'm trying to match this bend seen in the pic. I have all the dimensions but again how do i determine the radius?

 

[Desolation]

Looking straight down onto the tube you want to know the radius of the center-line.
You can eyeball this using a framing square.
Accuracy to under a half inch is really not required as dies (USA) are generally only available in 1" to 1/2" increments.
Finally the radius should be at least 2.5 to 3 times the size of the tube, thus 1" tube is a 3" min radius.
Hope this helps.

 

[UK4X4]

That looks like a wilderness rack

they use 3/4" too

scale of the dwg and make an estimate

 

[OverlandZJ]

Desolation, thanks and i think i follow. Taking a break from cutting the lawn, then i'll take out my framing square and a template i copied of that bend.

UK, thats not a Garvin product but the 3/4" material selection is to match my Wilderness rack. Your looking at a basket made by Cross Ent on my buds YJ.