Banked
turns are relatively easy to build. (See Illustration #7A - 7B -
7C) Cut out a "horseshoe" shaped piece of thin cardboard
like the drawing to see how easily this is done.) It took Hasse, Ogilvie,
DaPron, the Tunkels (and former track builder Chris Dadds) a lot of
trial, error and experience in order to learn how to construct wide,
high-banked turns and get them ultra-smooth so cars don’t "launch" going
in or coming out of the turns. In the case of wide King layouts and
Hillclimbs (which have a high bank which can drop as much as three
feet from the top straightaway to the lower level where the drivers
stations are located) it is sometimes necessary to have three different
radii all in the same turn. Damon uses a router affixed to a pre-determined
radius point to cut the outside of all his turns and bank pieces.
This
gives an ultra-smooth outer-edge which he later uses as a "guide" for
his special router "plate" (See Illustration #8 & #9)
to cut the first (outside) slot. Once he’s cut the outside lane,
leaving a 6" to 7" gutter, the roller bearings are removed;
a special pin bar installed, and he uses the first routed lane as a
guide to rout the other seven. This method is called "elliptical
routing" - pioneered by Hasse Nilsson - and gives modern tracks
much smoother entrances and exits to the turns. Look at the difference
between old, sixties tracks and modern layouts and you can actually
see the difference. Old tracks started a turn at the very end of a
straightaway and the next straight started right at the end of the
turn. With elliptical routing, the turns start sooner and go further.
Elliptical routed turns are not 90 degrees to the slot like the old
layouts.
If
you’re not able to use Damon’s method of cutting the
outside radius of turns, you’ll still have to lay your turns
out and scribe a pencil line using a radius point far enough back to
get the amount of turn you wish. You can use a sabre saw to carefully
cut this radius, but should you use this edge as a guide for your router
you’ll need to use a belt sander and get the curve as round and
super-smooth as possible. If this not possible, attach the router to
your radius point and having someone hold the radius guide point while
you slowly and carefully rout the slot.
CAUTION:
When routing the slots, run the router in one direction only -
preferably forward. Never pull the router backwards. This can change
the radius point and cause the slot to become too wide. Always rout
the curves and high bank pieces while still flat. Also rout for your
braid recesses before you assemble the track sections and rout the
straights. NOTE: Routing braid recesses requires a special router bit
(See Illustration #10) which has a pin which rides down in the slot
and the slot is the guide for the router. If you have access to a local
machine shop they can make you one of these.
Modern
track braid and wire- available from several and is available in
wider
widths and varying thickness. Most track builders now use
nickel-plated copper braid which is 9/32" or ¼" wide
that has more strands and is smoother than 60’s variety. This
carries the current better and cuts down somewhat on wear and tear.
Braid recesses must be carefully routed so the braid will actually
rest .010" to .015" BELOW the racing surface. NEVER
have the braid flush with the top of the surface, especially in the
turns,
as tire wear or gears too close to the track, etc. (This is why you
should ALWAYS tech cars prior to BOTH practicing and racing!) Flush
braid tends to "peal" up the leading edge, causing constant
repair headaches. There is a braid available through a company in San
Antonio, Texas, called Magnatech, which is a combination copper-steel.
While a bit more difficult to install, and with a slightly higher price,
the advantages are numerous. With Magnatech braid you get five to seven
years of life and don’t have to replace the braid in the turns
nearly as often as you will with standard copper variety. Another advantage
to copper-steel braid is that you can use neodymium magnets - called "traction" magnets
- affixed to the bottom of cars. This virtually eliminates the need
for the application of traction substances (called "glue" by
its devotees) and does away with the mess associated with "glue." We’ll
discuss glue in a later chapter. If you want information on Magnatech
braid, contact former TOA Board Member Jim Honeycutt at (210) 308-6909
or 210-981-2419. Also, H.O. and 32nd scale cars already use magnetic
attraction. (See www.slotcars.net, www.scalextric-usa.com and www.wizzardho.com
for examples.)
Once
you’ve routed all your turns and bank pieces it’s
time to construct the straightway. To save time, add "guides" on
the work table to hold the 1" x 4" x 40" (or 41")
supports (See Illustration #11). Once in place, roll carpenter’s
glue across the top edge of these supports and carefully lay the pre-trimmed
40" or 41" wide straight section so the outer and inner edges
are even and flush with the edge of the surface. Using your lane guide,
(See Illustration #5) install staples with your pneumatic stapler,
putting at least one or possibly two between each mark you’ve
made for the lanes. If you don’t have access to a pneumatic stapler,
pre-drill and countersink holes in the same places you’ve marked.
Fasten the running surface to support brace pieces using 1" sheet
rock screws. You’ll also need to glue and sheet-rock screw the
2" x 4" end cap pieces where the sections are joined together
with the bolts.
On
the King track Damon built for me, he pre-trimmed both ends of the
MDF sheets
to give much straighter, smoother edges for the joints.
His straightaway sections were actually only 90" in length once
he trimmed 3" from each end. Once all the straight sections were
completed the track was assembled. The legs were temporarily installed
- then he installed the bottoms, one section at a time. As the bottom
was completed on each section, the adjustable legs were permanently
attached by gluing and screwing to the bottom piece. If you do not
wish to install a bottom to the track or your straight sections, go
ahead and glue and screw the adjustable legs at this time. Do not tighten
the adjustable leg bolts until you’re satisfied that the top
surface is where you want it and the surface is smooth and level. You’ll
tighten and add a sheet rock "locking" screw once you are
satisfied with the overall surface layout and do this just prior to
painting.
CAUTION:
Sheet rock screws have a razor-sharp point! Be careful or you’ll
get extremely nasty cuts should you rake an arm, hand or finger across
one! Any exposed sheet rock screw which extends down
below the surface and could cause harm later should be knocked off.
This is done easily by hitting sharply with one or two hammer blows
to bend it - then scrape it off or pry it loose with a screw driver
or the end of your claw hammer.
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