I found this somewhere else on ns so i figured it'd be of use here.
RAMP:
6' tall
8' long ramp
Detachable ramp
Snow holders
MATERIALS:
11 - 8' studs (2x4's)
1 - 4'x8' piece of 1/2" thick plywood (whatever you want for quality, weather treated is better but more expensive)
1 - 1Lb. box of 2.5" screws
5 - 2' peices of small scrap wood about 1" thick
INTRUCTIONS:
1. Cut 4'x8' plywood in half the long way so you have 2 2'x8' pieces.
Cut one of those pieces at 2' long so you have a 2'x2' piece. The rest
of the plywood is scrap.
2. Lay 3 8' studs on the ground and screw the 8' long piece of plywood on top. This will be the ramp.
3. Cut 4 of the remaining 8' studs at 6' long. Make good cuts because
you need both ends of these studs. Keep the 2' pieces for later.
4. Cut 1 of the remaining 8' studs into 4 1' 3/4 long pieces.
5. Use 2 of the 2' studs and 2 of the 1' 3/4 studs to make a box. It
should be 2' square if you did it right, the same size as your piece of
plywood.
6. Screw the 2'x2' piece of plywood on top of this box. This is the top platform.
7. Use the remaining 2 2' studs and the remaining 2 1' 3/4 studs to
make another box, the exact same size as the first. This is the bottom
of your tower.
8. Screw the 4 6' studs upright into the inside corners of the bottom
box. make sure you use enough screws to make it solid. I used 3 on each
leg.
9. Put the top box on top of the legs and screw it on the inside of the corners. Again, make it solid so it holds up.
10. Cut the last 2 8' studs to make diagonals for the tower. This is
very important. This is what will make your tower solid and sturdy. If
you buy an extra stud you can make 3 diagonals for even more sturdiness.
11. Get someone to help you hold the ramp up to the tower. Make one end
of the ramp go right benieth were the top box overhangs. (see pictures)
Screw a 2' 1/2 stud on the legs right benieth the ramp so the ramp is
held up by the stud. (look at pictures for better visualization)
12. Make some sort of mark on the supports of the ramp so you can make
a 90 degree cut that attaches onto the stud you just screwed onto the
legs of the tower. (again, see pictures)
13. After you make the 90 degree cuts, your basically done. The rest is
just touch up stuff and making the whole thing more solid. Add those 2'
scrap pieces along the top of the ramp. Cut some pieces that fit
between the long studs on the ramp to close up the bottom end. then
just customize the rest to how you like it.
POSSIBLE ADDITIONS:
Ladder
Stairs
Walls around tower for smoke shack/porta-pottie
Rubber on top box for grip
Paint graphics/sticker it to hell
Speakers and stereo for tunezzzzzzzz!