3½ Quarterpipe:
Materials:
Skating Surface
(2 sheets of each) - 1rst layer 3/8 inch plyboard (just get low quality
sheathing) 2nd layer exterior grade 1/4 inch plyboard or 1/4 masonite (masonite
sux here oin the east coast)
Transition Sides(1 sheet) -5/8 inch plyboard (low quality works)
Deck (1 sheet) - 1/2 inch plyboard (exterior grade)
2 x 4's - 50
alot of screws
1. Figure how much transition curve you want (in feet &
inches) and how much vert, if any.
2. Tie one end of the string around the push-pin and stick
it in the sheet as shown.
3. Holding the string taught, measure out exactly the
amount of transition (see step one) and mark this on the
string with an ink pen.
4. Tie the drafting compass to the other end of the string
and tighten it so the slipknot is right on top of the mark
you made.
5. Holding the string taut, swing the compass from the
sheet's edge in a quarter-circle, marking the template
with the chalk. You may need to move the contraption
around to get the desired curve and best use of space!
6. Place sheet on sawhorses and cut out templates
carefully.
NEW ADDITION ON DECREASING TRANSITIONS:
7. If you want to make a ramp with a decreasing
transition, you need to modify the above steps and instead
of using a push-pin, use a round object that is 6 inches
to 3 feet in diameter, such as a paint can or a round
garbage can. Attach the string to the round object and
somehow secure it to the wood in place of the push-pin in
step 2. As the string winds around the round object, it
will get shorter and your transition will become tighter.
This is called a decreasing radius transition and it is
very cool when making launch ramps and quarter pipes.
Experiment and eyeball in a cool tranny.
Now use these pictures as guidleines for the reast of the ramp:
