Thanks! That's why I made the video. Lots of folks show what they made, not a lot of why they did what they did. I ended up making a second "heavy" set. I ripped the corners off of 4x4's to make octagon posts. I left them the full 8', tied the top with rope and just let them twist and bind. I used 3 sections of 1 3/4 conduit for the cross pipe. We use it to hang double. You can see it in my Cut Bank video, we hauled it all the way to Glacier. Unfortunately I lost the footage making it so I wasn't able to make a video. Maybe someday the cloud will give it back to me or I'll find it.

I would be confident with 300 lbs. I've had maybe 250 in mine without any issues. I'm not sure the gauge of the conduit but it's 1/8 or 3/16 thick. I chose it because it was common (easy repair or modification) it came pre-threaded (I wanted it to be in two pieces). The force on the pipe is mainly compression which should have strength far beyond a load for this purpose. I'd worry about the tripods failing before the pipe.