![[Drawing: overhead diagram of ramp segments]](ramp-18a.gif)
![[Drawing: diagram of support positions]](ramp-18b.gif)
Ordering Materials
Example ramp:
Two level landings, each 58" x 98 1/2"; 29' of sloped surface required.
Use two 116" modules and two 58" modules to obtain the needed length
(other combinations are possible).
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Draw an overhead view of the ramp
and make several copies. On the first copy, determine the number
of landings and modules needed. Pages
22 through 26 describe the materials needed. Begin
a materials list, keep a separate page for each landing and module
ordered so that during construction pieces can be matched to their
intended purpose.
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| On the next copy of your overhead view, determine the number of support structure needed. Pages 27 and 28 describe the materials needed. You can estimate how long each 4x4 needs to be by adding 34" to the distance between the ramp surface and the ground for each post location. Remember that the legs of the support structures do not have to be equal in length. Also, if you are placing 4x4s in the ground for handrail support at the bottom of the ramp add at least 2' for each sunken 4x4. Determine the 2x6s needed for the cross supports for the landings and modules. Add this material to your list. |
Now determine if 2x4 diagonal
bracing is needed, keeping in mind that diagonal bracing is needed
when the top of the cross support is more than 21" off the
ground, and that diagonal bracing is needed on each side of the
4x4 support posts. Also determine the number of gussets you will
need and the number of 1'x 1' plywood pads needed for the base
of the support posts (thirty-two 1'- square pads can be made from
a 4x8 sheet of 3/4"-thick plywood).
Determine the number of 3/8"
carriage bolts needed to connect modules and landings together
(three per connection). To determine number of 1/2" carriage
bolts, remember 4x4's with diagonal bracing require 10" bolts,
4x4's with gussets require 8" bolts, and 4x4's bolted to
only one cross support require 6" bolts.
The next step is to determine the
dimensions for the guardrail/ handrail (see page 34). Decide
if you are going to use plowed 2x6 for the top handrail or if
you will have a 1 1/2"-round handrail.
On the overhead view of the ramp
determine the lengths needed for the guardrail. You should have
an equal number of 2x6s and 2x4s. Use the longest possible continuous
2x6 for your top railing. If you have a 15' long section of ramp,
order 16' long boards. (Maintain a 4"-spacing between the
spindles, ten 30"-long spindles per 59" run of ramp).
The last step is to determine lumber
for steps or boardwalks that might be needed. You are now ready
to combine all of the lumber needed onto to a materials order
form (page 20). Keep the individual component sheets to refer
to during construction. This will reduce the chance of using the
wrong lumber for a particular component.