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The cantilever gate features the ability to slide along the fence line without requiring any lateral space as swing type gates demand. An automatic electric operator can be easily added to this type of gate. The fact that it requires no leading edge roller to support the weight of the gate makes it ideal for areas where snow and ice would inhibit such a roller. Those leading rollers will sink into asphalt also.
This information is provided as general guidelines in construction of cantilever gates. Calculating materials to be used and gate sizes can be a tricky proposition best left to a professional engineer, architect or atleast an experienced gate builder familiar with common building techniques. However, the smaller residential gates are not outside the scope of the do-it-yourselfer.
When constructed of pipe frame, as with chain link gates, the opening sizes can be up to 32' using a single leaf or 64' using a double cantilever. The maximum size does require a two handed effort and may be difficult for small persons to move. If an electric operator is to be used, the gate must be built precise so it slides easily and maximum widths should be decreased (match operator maximums to gate size).
Aluminum cantilever gates can be wider but generally are more expensive. Ornamental steel or wood gates are similar, but maximum widths must be less due to possible weight problems. In cases where the width must be greater, a leading wheel can be added. Extremely heavy or large gates can be installed on railroad tracks with leading edge, train style, steel wheels.
Crash proof security cantilevers are available that are built like a box, two gates about 18" to 24" side by side and welded together to form a rectangular box frame. The post and roller system is doubled so each gate rides in rollers. The gate passes between the posts including the latch posts. A steel pipe or bar can be slid through the gate in the closed position so it can not be dislodged from the latch posts, even by a speeding vehicle crashing into it.
Residential Cantilevers are usually smaller in size and do not pose any particular size limitation problems as long as construction guidelines are followed.
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The counter balance should be 1/2 the length of the gate opening. Minimum counter balance should be 4' long. If an automatic operator is to be installed, the counter balance may need to be longer so the operator can 'pull' the gate shut by the rear of the counter balance. Always choose the operator and gate before construction begins. |
The vertical bracing should be spaced 4 to 6' apart. If 2 1/2" sch. 40 pipe or comparable is used 5' spacing is adequate. The rollers ride on the horizontal outside frame. Support for the top and bottom of the frame is essential.
| Post sizes are important. Chain link cantilevers require 3" O.D. roller posts
for widths up to 10' opening size. Use 4" O.D. posts up to 20' and 6 5/8"
O.D. posts up to 32'. These specifications are for 6' high gates and shorter. For
taller gates increase post sizes at each step and use 8 5/8" O.D. posts for 32'
gates. Concrete footers need to be significant. 18" diameter x 42" deep is recommended for 3-4" posts, 24" diameter x 42" for 6 5/8" O.D. posts and 30" diameter x 48" for 8 5/8" O.D. posts. Increase bottom diameters 6"; creating a bell shaped hole. The up and down stress with these type gates will 'work' even the largest posts out of the ground. Poor soil conditions, such as sand, will require larger footers. |
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