This graveled alley, lined with granite, leads directly to the house. Just missing a hoop to brighten up the garden entrance. Each spring, roses or clematis can grow there by standing out against a background of greenery.
Hoops and gantries are often used to span walkways or gates. More ventilated and discreet than wooden constructions, metal versions are also easier to machine when it comes to arched shapes. Such as the model presented, made for the most part from arched concrete reinforcing bars. Based on the principle of mesh with wide mesh, it consists of two amounts connected by a hanger.
Each amount consists of three concrete reinforcing bars 14 mm in diameter and 2 m in length. The base of the irons is heat appointed to facilitate
penetration into the earth while at the top, they are welded inside an angle of 30 x 30 x 380 mm, the length of which determines the width of the arch.
Before assembly, each angle is pre-drilled with two Ø 10 mm holes, 80 mm from its ends, for bolting the assembly. The irons are then welded by keeping them square with respect to the latter, and well parallel: one in the middle, the others on the edges.
The uprights then receive five bars of Ø 10 mm. Clamped one by one, they are welded on either side of their ends with a Ø 2.5 mm electrode. They respect all along a spacing of 300 mm.
The two uprights must be 180 cm apart to allow the arch to span the driveway, with a total width of 170 cm. To give the bow the proper width, with an arrow of 70 cm in the center, three bars of 260 cm are needed. They are bent gradually, under the foot and on the knee, until the desired curve: the first serving as a model for the other two. At the end of work, their ends are slightly bent inwards to weld angles.
Once the two angles pierced in agreement with those of the amounts, the hangers are assembled by bringing as much care to their parallelism. Eleven bars of Ø 10 mm are then added, at a regular spacing of 21.6 cm.
Finishes and assembly
The welds are carefully trimmed before applying two layers of "green garden" anti-rust paint on the set. After complete drying, the arc is secured to the uprights by four bolts Ø 10 x 20 mm, tightened by corresponding nuts.
The ark can now be transported to its location and erected there. The tips of the uprights are then sunk into the ground about 40 cm deep. On either side of the aisle, the operation is carried out gradually with the help of a hammer and a hammer placed on the lower bar. Verticality is controlled at the bubble level in both directions.
Climbing plants may be installed at the foot of the studs on one side or both. When they begin to develop, it will be enough to ligate them to the irons of the arch to ensure a harmonious distribution.
The irons of each amount must be paid to facilitate their insertion into the ground. Heat the end to red using a butane gas torch or propane, equipped with a lance "Cercoflam".
Quickly, wear the heated part on an anvil or heavy mass. Hit the hammer for a square section, then stretch the metal tip. It often takes several heaters...
At the other end, place the first iron on the lower flange of the angle, pierced with two Ø 10 mm holes. Solder after adjusting their perpendicularity using a square and vise clamps.
Continue the work by assembling the same two other irons, then the series of bars. By measuring the intervals well, weld these intervals on both sides of the intersections to reinforce the hold.
Bending on the spot the three bars of the bow is wise, because it allows to adjust the width. For lack of specific material, they are bent with both hands using the foot and knee.
For a correct positioning of the angles, the ends of the hangers are folded on 5 cm. Heat the bar to red and crimp it inwardly levering with a piece of tubing.
To benefit from a comfortable working position, it is more practical to first weld the two lateral hangers to their end angles and to fix the eleven bars in the process.
Add the central hanger and then trim all the bow and stud welds. Start by grinding them to the grinder and finish with the half-round file, to eliminate the rough edges.
On each element, brush the surface rust and degrease with white spirit. After 24 hours, apply two coats of green paint to protect and decorate the metal.
After complete drying, proceed to the final assembly by bolting the angles of the bow and those of the uprights. Tighten the nuts and apply a touch of paint to hide these fasteners.
Straighten the arch and place it over the aisle. To break the base of the uprights, take turns knocking on their last bar by interposing a martyr. The structure must be perfectly level. It will remain to install the climbing plants which, the season come, will make appreciate their scent with each passage.