How to Determine the Number of Arms to Be Used in Cantilever Racks

When racks are installed, they are placed on extended arms that provide support. These arms need to be placed in a manner that will allow them to support the weight of the products placed on them. The correct placement ensures that the racks will not sag or break. Incorrect placement or overloading of the racks (namely, if the weight placed on the racks is more than the load capacity the racks and arms can handle) means that the racks will break. On the other hand, when the rack sags, while the rack is able to handle the load, it means that the arms are not placed with proper spacing between them. This article explains how you can adjust the arms to avoid sagging through correct determination of the number of arms to be used and ensuring accurate spacing between them. You will also need to adjust load equally on the rack.


  1. 1
    Determine which products are likely to be stored on the racks. The load capacity of the rack can be determined only when you are sure about what kind of products will be placed on the racks. This includes knowing their total weight.
  2. 2
    Conduct a dry run. Get hold of the material or the product that will be placed on the rack. Here, it is a good idea to consider the maximum amount of weight that will be placed on the rack. Install a racket with two arms and place the product onto it.
  3. 3
    Check the amount of load deflection occurring. Make a note of the amount of load deflection. Remove the weight from the rack.
  4. 4
    Correct the problem. If after Step 2, the rack sags (shows load deflection), attach a third arm exactly in between the other two arms. Repeat Step 3.
  5. 5
    Add more arms. If the rack is still experiencing load deflection, remove the third arm and place two arms directly between the arms at the end. This should be performed in such a manner that there is equal distance placed between all the arms. Repeat Step 3.
  6. 6
    Repeat step 5. If the racket is still experiencing some load deflection, the number of arms should be increased. Always maintain an equal distance between all arms.


  • Consult designers before installing structural pallet racks. Getting professional help will allow you to use your space optimally.
  • The number of arms are calculated in a manner that ensures that the rack maintains a rigidly flat position at all times.
  • The load placed on the rack should never exceed the length of the rack.
  • The load should never be placed at the edge of the rack; this could make the rack and the structure tip. The first load should always be placed at the back of the rack, and then more weight can be placed in the front to balance the weight.


  • Ensure that all workers are equipped with safety gear including hard hats, industrial shoes, etc.
  • Only qualified personnel should handle the equipment and power tools.
  • Instructions provided by your supplier and the manual should be adhered to at all times.
  • Improper installation can be hazardous to property and people.

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Categories: Home Improvements and Repairs