for your cantilever rack system

## Determine the number spacing of arms

The load must be supported by enough
arms to prevent load deflection.
Deflection may cause damage to the load
being stored as well as the arms (figure
A1 as shown below).

If deflection is not present it is
acceptable to use a two arm system as
long as this does not create an overload
condition. If the load shows deflection
use three blocks as shown in figure A3
or four blocks as in figure A4.

**IMPORTANT:** The load
should overhang the end arms by one-half
the distance from upright centerline to
upright centerline. Failure to observe
this measure may cause an overload
condition on the arms

## Determine the length of arms

The depth of the load should never
exceed the length of the arm. A 48″ wide
bundle of plywood requires a 48″ long
arm, bundles of steel 24″ wide require a
24″ arm and so on. Rated arm capacities
may be seriously diminished if proper
loading techniques are not observed.
Figures B1, B2 and B3 illustrate correct
and incorrect arm loading.

**NOTE:** All arm
capacities are based on an evenly
distributed load as in figures B4 and B5
below.

## Determine the height of upright

When determining the height of the
upright it is important to consider the
ceiling height, forklift reach,
sprinkler systems and other factors,
such as local building codes that might
affect the overall height. The height of
the upright in figure C1 is determined
by adding the base height, the number of
loads to be stored, the arm thickness
plus 6″ clearance between the load and
next arm.

**IMPORTANT:** The load
placed on the base does not diminish the
rated capacity of the upright. Thus, the
heaviest loads should be placed on the
base.

## Determine arm and upright capacities

As previously discussed, each arm
supports an equal amount of the load’s
weight. By determining the number of
arms per level and dividing it into the
weight per level, the required arm
capacity can be determined (see example
at above). To determine the required
capacity of each upright, multiply the
number of arms per side by the load on
each arm. In figure D1, each arm holds
2500 lbs. Twelve arms per side times
2500 lbs. per arm equals 30,000 lbs.,
which when divided by three uprights,
results in a required minimum capacity
of 10,000 lbs. per upright. The correct
upright can be selected by matching the
minimum upright capacity of 10,000 lbs.
with the upright capacities set forth on
the following pages. Assuming a 48″ arm,
the U1061-NS on page 22 with 10,200 lbs.
capacity and the U1061 on page 23 with
12,600 lbs. capacity are the only
uprights that will handle the load.
NOTE: The Series 1000 MU1057 has only
3100 lbs. capacity while the Series
20002U1062 has 8600 lbs. capacity

**IMPORTANT**: The load
placed on the base does not diminish the
rated capacity of the upright. Thus, the
heaviest loads should be placed on the
base.

## Determine brace length

Brace length is defined as the horizontal distance from centerline of upright to centerline of the next upright. Refer to the various brace set charts for the brace length that most closely matches the arm spacing determined in step A.