How to make a sliding steel gate

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Step 1: What You Will Need

Materials needed:

– 50mm x 50mm square tubing (you will need to work out how much according to the size of your gate)

– 15mm x 1.6mm round tube

– 12mm round bar

– Any material of choice to fill in the panels

– 80mm radius gate wheels one for each panel plus an extra one

– nylon top rollers 2 x sets

– parliament weld-on hinges 2x for each 2 joining panels

– 50mm x 5mm flat bar (for the rail)

– 16mm round bar (for the rail)

– 75mm x 50mm lip channel (for the rail)

– Paint

– sliding gate motor (minimum 500kg pulling force)

– rack

– concrete mixture

Step 1: What You Will Need


– Angle grinder

– cutting and grinding disks

– drill

– 15mm drill bit

– welding machine

– spray gun

– spirit level

– nylon building line and line level

– pick and shovel

Step 2: Fabricating the Panels

  1. The gate consists of several vertical panels, that make up the complete assembly. For driveway and other large gates, you may use a panel of 600 mm width. The height can be made to your liking or the height of your boundary wall. There’s no specific height there.
  2. The formula you will need to use to work out the number of panels is simple. The gap between the two posts or walls that the gate needs to fit in divided by 600 mm and add 2 panels. These 2 panels are needed to stabilize the gate and to connect to the gate motor that sits on the side, adjacent to the wall that you need to slide it against.
For example, if the gap is 4 meters= 4000mm / 600mm = 6.6 panels. Round it up to be on the safe, therefore you will need 7 to close the gap plus 2 extra to take up the turn and the gate motor. Use 50mm x 50mm square tubing to fabricate your panel frames, cause the gate wheels you need to use has a base of 50mm. You are now ready to fill the panels with whichever design you prefer.   Next up is to fit bushes in the bottom of the frames where your gate wheels will swivel in. Drill 15mm holes in the bottom horizontal part of the frame. one-hole 40mm from the left in the centre and the other one 40mm from the centre from the right. It is advised to use a 15mm x 1.6mm wall round tubing that is cut into 50mm lengths and then welded into the bottom on both left and right sides holes drilled in the frame. Lastly, you will need to fabricate the roller bracket. You may use a double configuration, which is a very strong and precise method of keeping your gate where it needs to be.

Step 3: Gate Assembly

Now you are ready to assemble the complete gate.

Place the panels next to each other and make sure that the bottoms of the panels are 100% level with each other. It’s very important, if your panels are not 100% equal in length which happens often, the top of the gate does not need to align perfectly. The bottom does.

Weld in the Parliament hinges, one 200mm from the bottom and one 200mm from the top. The hinges used must have an offset of 30mm. The hinge pin needs to be 30mm from the pin and not flush otherwise your gate motor rack will not work and will bind and break everything.

The gate wheels are weld-on, but for this application, they need to be modified to be able to swivel. Remove the pin that holds the wheel in the bracket. Remove the wheel from the bracket.

Now mark out a point in the centre of the bracket and drill a 12mm hole. Cut a 50 mm piece of 12mm round bar and weld it in the hole on the inside of the bracket.


Assemble your wheel.

Test fit if the 12mm round bar will fit in your 15mm bushing.

If not, use a reamer and clean out the inside of the bushing until it fits. Add a 12mm inside diameter flat washer between the wheel and frame on the shaft. put enough grease on everything. It will just make it easier to move and operate.

The Wheels start at the end where the gate closes against the wall or post, thus the panel where you stand in front of the gate and it closes to your right will be the first panel on your right. You must skip one bush and insert the next wheel in the same bush as the previous panel. One wheel per panel, except the very last panel, will have 2 wheels in that panel. The reason for this will be evident when you assemble the gate. Paint your gate.

Step 4: Installing the Rail

The rail installation can be very tricky and may take a few attempts to perfect this.

Use a 50mm x 75mm lip channel for the straight parts of the rail. Make sure when you purchase them, that it is 100% straight. Now measure the length of your gate assembled. That will be the length of the rail on both sides of the bend. Turn the lip channel onto one of its sides and weld the 16mm round bar onto the side in the centre.

For the bend, a 50mm x 5mm flat bar can be used. Bend it in a 90-degree configuration around an inflated 15-inch truck or pick up tyre. That seems to be the ideal radius for these gates. Bend the round bar also around the tyre and weld it onto the edge of the flat bar.

You won’t need to weld the whole round bar. Short little space welds about 300mm apart are sufficient to prevent the rail from warping.

Dig a trench in an L shape where you want your gate to slide, about 200mm deep and 300mm wide. Weld off-cut pieces of steel perpendicular to the rail on the bottom. This will improve the strength of the entire structure. When you levelling the rail, hammer them in the soil to keep the rail in the air and level. It makes it easier when pouring the concrete.

When levelling the rail, use spirit levels, building line and line levels, laser levels or whatever you have at your disposal. JUST MAKE SURE THE RAIL IS 100% LEVEL. The gate will derail even if there is just the slightest divot in the rail.

After you’re sure that your rail is straight and level, mix your concrete and pour it up to the top of the lip channel and flat bar so that only the round bar is exposed. Leave it to cure for approximately 2 days

Step 5: Installation

The top roller guide will differ, depending on what you have to mount it to. It can be mounted against a wall or concreted into two 100mm x100mm square tubing’s where you can mount the rollers, as long as you have a sturdy mounting point to prevent the gate from toppling over.

it is advised to put the gate on the rail with the centre of the gate on the rail bend. That keeps it upright and easy for you to mount the roller guide in the correct position.

Now that the gate is on the rail and secure, you can fit the gate motor and weld the rack on the gate. Remember, the hinge pins need to be 30mm offset from the gate panels. Your rack needs to be 5mm closer to the panels (25mm from the panels) this will allow the rack to move apart around the bend or else it will bind and start pushing the gate in a straight line. Cut the rack after you have welded it right in the middle under each hinge pin. Then, move the gate one panel forward and weld another piece on

The last thing you have to do is to bolt the catch in the end where the gate closes. This adds sturdiness and makes the fixture more secure.