| Fabrication
Unless rails will sit on
flat surfaces, always wait to fabricate rails and other metal
obstacles until after the concrete has been placed and
finished. Whether you are doing it yourself or having the
rails custom made it is much easier to take the measurements
from the finished concrete and then fabricate the rail than to
try to form the concrete surface to fit a rail that has
already been built. Steel is the most common material used in
the fabrication of rails and similar objects. Steel can
easily be primed and painted to prevent rust without much
additional expense. Galvanizing the steel to prevent rust
essentially doubles the price of the material plus the
galvanized layer will eventually grind off. Although
beautiful and weather resistant the material for stainless
steel rails will cost about ten times the price of steel.
However, stainless steel might be considered for a few
carefully selected locations.
Rails should be fabricated from a minimum 1.90 outside
diameter (O.D.) Schedule 40 tubular steel pipe. For obstacles
made out of square stock or similar material the walls of the
material should be a minimum of ¼-inch thick. Make sure to
grind down all welding beads and remove burrs to make for the
smoothest grind and to protect skaters during falls. If the
rail is to be subjected to exceptionally heavy use consider
adding gussets to any support posts.
Attaching Rails
The easiest way to attach rails and other metal elements is to
drill holes in the finished concrete after it has cured.
Bring the fabricated rail or other element to the park and set
it in place. Get some help, as this will be easier with at
least two people. Next, you mark where the holes will be
drilled and then set the obstacle aside. Drill holes into the
concrete at the locations marked using a ¾-inch carbide drill
bit in a rotary hammer. Both of these items can be rented by
the day or week at an equipment rental store. In a pinch you
can use a masonry bit in a regular drill, but this will be
slow going. The bit will not drill through large aggregate
and will wear quickly.
After the holes have been drilled, blow any concrete residue
out of the holes with compressed air. Bolts can then be
securely anchored into the holes using one of several
anchoring compounds available at masonry supply stores. Ask
for a recommendation at the store if you do not have a
preference. These anchoring compounds are quite tenacious, in
many instances the concrete or the fastener will fail before
the compound. A minimum of a ½-inch bolt with the head
machined off (to fit into the ¾-inch hole) should be pushed
into each hole after it is filled with anchoring compound. If
possible, set the rail in place now and allow the anchoring
compound to cure as outlined in the instructions that come
with the product. After the anchoring compound has set, lock
washers and nuts can be placed on the bolts and tightened.
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