The best way to fix Sagging in Large Gate

On a farm, sagging tubular steel agricultural gates are always a headache. There are several reasons why this problem develops, and there are also solid workable solutions.

Typically you have an 8’ tubular metal gate and a year or two after installation the far end of it dips so low you can only manage to open the gate about 1/3 of the way. If you’re an experienced farmer, you will know how to work around this problem. The first line of approach, of course, is to install the gate correctly. Don’t for a moment think that putting two of the lag style hinge hangers into a 4×4 post and then attaching the socket side of the hinge to the gate, and hanging it constitutes a proper and effective installation.

What you need to remember with gate hanging is that unlike the other fence posts in the system, the hinge post of the gate is a special member and requires special attention to make it stable. Particularly if the soil is soft or wet and/or freezing tends to lift things that are not below the frost line out of the ground. Any, or all, of these conditions in concert will greatly weaken the gate post. Finally, you need to remember that a tubular steel agricultural gate (in fact all gates) is a cantilevered affair, and at 6, 8, 10, or 12’ extension it puts tremendous load on the hinges and the hinge post.

To correctly install a hinge post, the best thing to use is a treated 6 x 6 timber sunk at least 3’, or preferably 4’, into the ground.

1. Prior to back filling the hole, dump a bag of dry cement mix into the hole.
2. Plumb the post with a spirit level or plumb bob and begin backfilling, compacting the soil and back filling every 12-18”.
3. Now that the post has been properly installed, it needs to be braced. Install another 6 x 6 post 4’- 6’ away and use the same process to install it.
4. Install one cross brace between both posts at the top of each post, and then another at the bottom of each post. To properly install the cross braces you must drill through the 6 x 6 posts and mount the cross braces in between, and insert countersunk ½” x 10” lag bolts through the 6 x 6 into the lateral. The lateral can be a 4 x 4. Treated lumber is also recommended. Repeat the same process towards the bottom of the post but do not allow the brace to contact the ground.
5. Now you need to install a brace cable from the upper corner near the top hinge to the lower diagonal corner of the brace assembly. To do this correctly, use eye lag bolts at each end, 2 pieces of cable with a turnbuckle in the middle and cable clamps. Set up the turnbuckle so that it is fully extended, and then securely attach one of the cables to each end so that they are taut.
6. Now it is simply a matter of tightening the turnbuckle to help maintain the square configuration of the brace assembly. This will very effectively help the gate post remain perfectly plumb. In the event that any sagging should occur, it is simply a matter of tightening the turnbuckle to pull things back into alignment.

Since we mentioned that the gate is a cantilever affair, and therefore most of the weight of the gate is supported by the upper hinge, it stands to reason that supporting the lower far end of the gate would relieve the stress from the hinge. The ideal item to do this is a gate wheel or gate caster with spring suspension. Gate wheels specifically intended for steel tube agricultural gates can be purchased from Lowes, Home Depot, Tractor Supply, Rural King, Runnings Supply, or Mills for example. Typical manufacturers of this type of product are Nationwide Industries, Nordstrand, Caster Connection, Albion, Northern Tool and Equipment, Shepherd Hardware, Fence Smart 4U, RWM Casters, and Tech Team Products.

We strongly recommend the Tech Team #767 13” Gate Wheel for this purpose. It’s design and construction are far superior to any other products available on the market.

• It is constructed from heavy duty welded steel plate (6mm thick) that attaches via strong U bolts to the tubular frame of the gate.
• The gate wheel has an integral 20mm/ 5/8” axle and a 13” polyurethane foam flat free tire.
• It is perfect for agricultural gates, chain link fence gates, and wide wood garden gates. This eliminates the possibility of the tire going flat, defeating the purpose of the gate wheel.
• It is a simple matter of using the 4 included hex nuts, brackets, and U bolts to attach the gate wheel to the end of the gate.

It’s suggested that you block up the end of the gate and elevate it about 1” and attach the gate wheel so that the wheel is firmly resting on the ground, and then tighten the 4 nuts so that the gate wheel cannot move, and remove the bracing you are using to hold up the end of the gate. The gate will now turn freely. The gate posts will remain vertical and the solution is a lasting one. This is a heavy duty gate wheel set that includes all the necessary gate wheel hardware and requires only simple hand tools for a great addition to a driveway gate or patio gate.