Anyway, I have built and tested a set that cost only $50 , and all of the parts came from Lowes, and harbor freight tool store.
List:
10ft of 1" emt conduit
10ft of 1 1/4 pvc
10ft of 1" pvc drain pipe (the really thin stuff)
4 1 1/4" pvc caps
2 5/16" eyebolts
1 1/4" hole saw
2ft of 4x4" lumber
2ft of 2x6 lumber
at harbor freight I got the 13" heavy duty tires on sale for $11 each, PN# 37767
(Beer consumption not included in $60 estimate)
start by knocking the bearings out of the wheels and make the bushings for them out of the thin 1" pipe.
the thin pipe rides perfectly on the conduit tubing, but its a tad loose in the wheel, so shore it up with a few wraps of electrical tape.
then (for the p16), cut the tubing 94" long and drill a 5/16 hole through an inch from both ends, these are for the eyebolts.
cut two 8" sections of the 4x4 and 2x6, and screw them together in an "L" like in the picture
holesaw both L pieces all the way through so they fit on the tubing.
Now it all goes together in this order: 1 1/2" long pvc, L cradle block 4 1/2" pvc, wheel, center pvc (64" or so), wheel, 4 1/2 pvc, cradle block, 1 1/2" pvc. You have to holesaw the pvc caps and use them on both sides of the wheel so they have something to butt up against. The eye bolts hold it all together.
cover the wood with a scrap of carpet or rubber, and add a couple of ropes.
I also put a squirt of expanding foam in the pipe ends to help it float.
And thats it, your craptrax are ready to go.
I have no idea how they will work on sand (never seen the stuff) , but on midwestern beaches, aka rocks and dirt they work great. Soft sand would probably need balloonier tires. (is that a word?)
the axle doesnt flex very much under my p16, but heavier boats would need a better axle.
Ill bet you could even add a tee in the center section for a handle, Craptrax deluxe!
Also I added an awesome sticker to my boat to scare new crew while i was at it!
