I've made these mountainboard-trucks quite a while a go but didn't document the process, however I think that, being quite strait forward in construction, you'll be able to figure out how to make them yourself at looking at the pictures.
What you'll need is:
- a length of steel U- profile, at least 2x40 cm. I used some galvanized stuff left over from installing a new heating system. It is quite thick, about 1,5 mm so a bit heavy but easier to weld and strong. To make it lighter I drilled holes in them.
- a lenght of 22 mm steel tube for the axles. I used 4 pieces of about 25 cm.
- 4x m10 bolts,locking nuts and 8x washers, to fasten the wheels. I've welded the bolts in the tube- ends.
- 2x m8 bolts, washers and locking nuts. These are used for the pivot axle.
- 4x big wheels with bushings . As you can see I've used very broad wheels for use on the beach, meant for use on a wheelbarrow. however these aren't the best, because they have roller bearings instead of ball-bearings but they where cheap and I've planned to replace the bearings.
- some steel-plate and/or construction 90 deg. angle brackets. I've used these to make the angled risers under the trucks,the pivot points and the foot-hooks on the board. I've a big box lying around left over from a home-improvement project some years a go. These are quite handy and strong but easy to work with and, since I've a lot of them, I use them often in my projects.
- Two bicycle saddles (yes, that's right, bicycle saddles!). These are important, I used the springs of them for levelling the trucks after steering, thus creating some sort of bushings.
- a handful of different size fastening bolts and nuts for putting together the springs, pivot-system, risers and board and trucks.
- A welder. I have a cheap arc-welder, just fine for this kind of stuff (so that's the reason I also enter the metal contest, who knows...). And however I'm not a good welder, I can stick metal parts together just fine...and ugly, but that is where the next tool comes in handy..
- An angle-grinder. for cutting the metal,that is with a cutting disk off-course and to clean up messy welds with sanding disks.
- A braking bench . Can be handy but if you are strong enough you can just stick with a workbench bank-vice to bent the brackets
- just some standard tools: Hammer to make things fit off course. The right wrenches for nuts and bolts that does fit together. Pliers for holding things that won't fit so you end up with still usable fingers for using the wrench. so you can try fastening things that did fit before you accidentally made them unfit by hitting them with the hammer. Screwdrivers for all the other things.
Of course you could also use them on a skateboard when you screw them under the kick-nose and tail.
I also have build a mountain-board but this needs some more reinforcement with fibreglass, so maybe I'll show that later.
Finally I use a skatewing that I bought lately very cheap and I'm still busy with a 6 m2 kitewing made of an old tent, but that's also an instructable to come (pffff, anyone knows where I can buy some more time? Would be a nice price for the next contest, winning project time!).
Off course you could use a kite or just gravity for a motor.
Any questions? I'll try to answer them...if I got some time left ;-)
I really would like to show you how I do extreme things with this rig but that off-course would be best with a video made with a Go-Pro Hero, which I don't own..