I cannot take credit for the overall design. I did fill the base with Sand on mine and epoxied the openings so it stays in. I also left the uprights detachable for storange. It is extremely stable.
If you are doing this for a Mountain Bike or anything with wider tires, cut (3) 2 1/2) connectors and use them in the middle sections. This will give you a wider tire opening. I am making one of these for my Mountain bike. If space is a concern, you can shorten the 7" Outriggers if you are using sand. The sand makes it very stable. I would guess I could have made them 4" and it would still be stable.
When gluing, you do not need to use PVC Prep. You are not holding water pressure in these, just use the glue. A hammer comes in real handy seating the PVC. The hardest part is making sure everything is aligned. Get sloppy with the glue, it gives you more working time.
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