I made the simplist slider two years ago. It is rather portable and has more than one use as i built it from a banana tube, pvc and some straps and ratchets. i drilled elongated holes for the straps to go through the sides of the pvc and tightened around belly of tube. I also used cinder blocks to weigh one end of the pipes down into the water and i used an anchor for the front too.
the last pic is a nice 2-3inch gouge in my awsome no name brand garage sale purchased board. i got it from the crash pic just before it. when i hit the holow ends of the pvc it made a nice bone cracking noise. it was like 6inches from hitting my foot. My dad freaked. i told him we'd put more weight on the up ramp so it wouldn't bob out of the water
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