- How to protect the wood?
- Which essence to use?
- Waterproof assemblies
- 1 MACHINING OF THE TENONS AND MORTISES
- 2 REALIZATION OF PANELS IN BLADES OF SHUTTER
Classic, this oak planter hides some manufacturing tips that ensure its longevity. Its volume allows it to accommodate shrubs of good height.
Cost: 40 €
Time: 8 hours
Equipment: hand tools, circular saw, woodworking machine (or combined)
Before building his planters, Nicolas Macaret studied ways to avoid stagnant water, the main cause of rotting wood. His judicious choices of material, assemblies and finishing are here guided by this requirement.
How to protect the wood?
There are indeed different solutions to protect the wood: coat the inner faces of the planter with a layer of sealant, based on bitumen or synthetic resin; treat the wood with a fungicide and insecticide product or wrap the earth with an insulating film...
In all cases, it is essential to provide good drainage and evacuation of water, to prevent rot of the root system of plants.
Which essence to use?
Soft woods (beech, poplar, linden...) are to be avoided because they are too sensitive to micro-organisms. Class 3 or 4 exotic woods can do the trick, but they are expensive and are more difficult to work with. The acacia, the chestnut, the alder, the oak (choice of our reader) resist very well in the time.
When you do not have a planer, the autoclaved pine (heart treated), available in DIY superstores and garden centers, is the simplest solution. Nicolas Macaret used recycled wood from old shutters.
To avoid water-retaining cups, the grooves are systematically placed above the tabs, the tops of the studs are cut to a diamond point and the horizontal edges are slightly beveled.
The collages are made with a polyurethane glue, which swells slightly while drying, allowing to fill any vacuum. The woods are treated with an exterior stain.
Finally, a geotextile is put in place to prevent the roots from seeping through the wooden boards.
• 4 uprights (595 x 80 x 80 mm)
• 4 high crosspieces (470 x 45 x 45 mm) and 4 basses (470 x 50 x 45 mm)
• 20 blades (443 x 93 x 27 mm)
• 6 boards for the bottom (460 x 77 x 27 mm)
• Polyurethane glue, geotextile felt, stain
1 MACHINING OF THE TENONS AND MORTISES
The posts are cut into 85 x 85 mm posts to obtain a section of 80 x 80 mm after roughing. The mortises are made with a chisel and chisel or a mortiser. One end is then cut into a diamond point using a circular saw.
The oak trays (50 mm thick) are delocated and wrought to obtain sleepers (45 x 45 mm). The tenons are made with a router or band saw. Finally, the shoulders are cut with a saw so that the tenons fit exactly into the mortises.
The lower beam is machined in a particular way; to prevent the ingress of water in the groove, it will be practiced on the panel. The crossbar therefore has a tongue on the top.
The router also makes it possible to make the chamfers that soften the edges of the uprights, as well as the rounding above the high rails and the chamfer on the lower rails, intended to facilitate the flow of water.
2 REALIZATION OF PANELS IN BLADES OF SHUTTER
The panels (shutter blades) are assembled without glue, tongue and groove on the sides and ends, to let the wood work.
On the other hand, the joints with tenons and mortises of the uprights and sleepers are glued (polyurethane glue) before being tightened.
Nicolas Macaret took care to hide the blackened faces of the recovered shutter blades by placing them inside the planter.
The bottom blades are laid edge to edge without being tight. After manual sanding (grain 120), the wood is stained and then isolated from the topsoil by placing a geotextile.