I would like to share the stand I built this past weekend, my constraints for this project were:
- Portable Poles - Shorter the better
- Strength - Needs to support 300+ lbs
- Material - Needs to come from local hardware store
- Cost - Keep it under $100
I decided on the Tensahedron design because they look super cool and because I think the feet won't sink as much into soft soil compared to the tripod stand. The issue is how to reduce the length of the 4 legs and how to connect them. What I decided to do was split a pieces of 12" long 3/4 EMT along the seam and expand/open enough to accept the 3/4 EMT leg sections. This required purchasing an addition 10' 3/4" EMT and 10' 1" PVC Conduit.
Here are the 12" sections of 3/4 EMT:
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The EMT has a seam where the tubing is welded at the factory, I figured this would be as good of any place to split. Looking in the EMT the seam is the dark line that runs the length of the segment:
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Marked the outside of the EMT:
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Cut along line with Angle Grinder:
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This is the part that took the longest to figure out how to proceed. My first try I used a crowbar to work along the opening but if I pried too hard it would deform the cut edge of the EMT and it made the conduit more elliptical than circular in cross section. Next I thought about reversing course and sqeezing the split tube back togther and making an internal connector however my attempts didn't get me a round result. My solution involved a hammer and some sockets. Starting with as with a 1/2" drive 14mm socket, 4" extension, 12" extension, impact drive extension. I started with the narrow part of the socket in the conduit and using a 12" and 4" socket extension and a hammer, pounded the socket down the length of the split conduit (I used the 4" extension to hammer against which isn't shown in the picture):
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The 14mm socket wasn't wide enough but a 1/2" drive impact socket extension was the perfect diameter. It took about 5 minutes for each sleeve to drive the various sockets through. Making slow progress:
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Here is the final result, you can see some crowbar deformation on the left of the tube. I slide the socket extension into the split tube to use as a base to hammer against to straighten the waves as much as possible.
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These pieces would structurally work as is however I was concerned about pinching fingers or cutting myself on the exposed split tube. I was also concerned that with time the split tube could either open or get banged up and not allow the pole section to slide together. The inner diameter of 1" conduit was a little too small, it would fit over the split tube but compressed it too much for the pole section to slide in. While I can not drill metal conduit, PVC is easy to do. The purpose to of the PVC is only to protect the split tube sleeve, I am not relying on it for structural support. I used a 1-1/16"/27mm hole saw to bore out the inside of 1" PVC conduit. I could only get the hole saw about 4" into the conduit so I had to make the PVC sleeves in 2 pieces, an 8" and 4" piece that I glued once installed on the sleeve. I attached the connection sleeve to the lower piece of pole segment by sliding the sleeve down 6" and drilling for an 8-32 screw. The screw is only to hold the sleeve in place. Once assembled there is little to no play in the joint.
I cut 12 pieces of 36" long conduit and finished the stand just like the other stands on the forum.
All together (temporarily as I am still trying to figure out how to hang everything):
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I was very impressed with the stand, it was rock solid. I tested it with me + 30 lbs weight and it worked great! This was not however the easiest build, expanding the sleeves took alot of hammering and did destroy the 4" socket extension I was using to drive the expanders throught the tubing. I only had a regular hammer, a small sledge would have made life easier. There are probably better was to accomplish this part, some kind of threaded rod and a screw attachment would be ideal. The second hardest part was cutting the EMT, I used a tubing cutter to do this part mainly because the tubing cutter curls the outer edge of the conduit while cutting which I think helps the pole segments slide into the connector more easily. The cutter I had was small, a larger one would have been better. I already had all of the tools and here is what I used:
- Drill Press
- 4-1/2" Angle Grider - Dremel would also work but would take alot of time
- 3/8" Drill
- Tubing Cutter
- Hammer - Bigger the better
- Sockets and Extensions
- Files - Flat and Round
- Glove - A must while handling the cut EMT
- Workshop Safety Equip.
Now I need to hit up the Goodwill to re purpose a carrying bag. A big thanks to everyone on this forum, looking back the hardest part was actually starting the project, the rest was easy compared to that.
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Originally Posted by Johnson
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