DIY Interior Light

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  • You can add a special atmosphere to every room, even using artificial light. Our wall-mounted light box is a brilliant example of how to give your rooms an exclusive touch. What's more, you can display small items in the two illuminated rectangular compartments contained in the light object.

    The light object consists of two parts: a rear panel with two narrow side panels and the front panel with two rectangular openings. This has two recessed broader side panels at the rear and three lighting rails with a cable leading to a triple plug.

    The following assembly instructions apply to 19-mm-thick medium-density fibreboard (MDF). You must adapt the list of materials accordingly if you opt for other materials or thicknesses.

    Ask your DIY store or carpenter to cut the required boards to size.


    1. Cut shelf openings in the front panel

    First use a pencil to draw the outlines of the openings in the front panel, following the specifications in our illustration. Then use a drill and 10 mm wood drill bit to bore a hole in each corner so that the edge of the drilled hole only barely touches the pencil lines, but does not intersect with them.

    Insert the saw blade of the jigsaw in one of the holes while it is switched off. You can now cut out the opening along the pencil line from one hole to the next. It is up to you whether to leave the corners rounded or whether to insert the jigsaw right into the angles.

    If you have a router with a parallel guide, you can also use this to complete the cutouts.

    2. Drill a series of holes for the shelf supports

    Place the front panel on the rear panel exactly as the pieces will be positioned once fully assembled. Now use a pencil to copy the outlines of the front panel cutouts on the rear panel. Remove the front panel again.

    In pencil, draw a line that is 8 mm below the cutouts on the back of the front panel and the front of the rear panel. Make five holes measuring 10 mm in depth along each of these four lines, following the distancing intervals in our illustration. You will use these holes later to mount the shelf supports for the perspex bases. The hole diameter is determined by the type of shelf supports used. Please note: Do not drill all the way through! Ideally, you should use a depth stop.

    3. Drill dowel holes in the front panel sides and front panel

    Since screw holes would disfigure the front panel, we decided to use wood glue and dowels for the joints. (If you plan to paint the front panel in colour anyway, you can also fasten the front panel sides from the front with screws). The holes will then be concealed by wood putty and paint. The advantage of using a screw fitting of course is that you can dispense with the laborious task of gluing with screw clamps and pieces of scrap wood.)

    Position the front panel sides on the back of the front panel where you want to mount them. Use a pencil to mark the outlines and positions.

    In the case of corner or T-joints, we strongly recommend using a drill template and marking points, or dowel templates as they are known. Measurements and markings alone will not be sufficient to position dowel holes precisely enough so that they lie exactly flush with each other.

    Using a drill and 8-mm wood drill bit, bore three dowel holes in the front edges of the front side panels. Copy the positions of the holes using dowel templates to the back of the front panel.

    A drill template is a device that is attached to the workpiece by means of a screwing mechanism. This device guides the drill bit vertically through a metal collar directly into the wood.

    A dowel template is a metal pin with marking point. You insert this pin into the holes on the front side so that you can transfer their positions. To do this, you press the predrilled workpiece precisely in position on the surface of its counterpart.

    Dowel tips:

    Use a wood drill bit to drill holes with the dowel radius into the two pieces that you want to join. The two drilling depths should amount to the dowel length plus 2 mm. For this reason, you should ideally use a drill bit with a centring tip and a depth stop: the latter is a locating stop ring with a setscrew that is fixed to the required drilling depth on the drill bit. Never drill a hole that is deeper than two thirds of the material thickness.

    4. Glue the front panel and front panel sides together

    Apply glue to the dowel holes and the gluing surfaces of the front panel sides and then insert the wooden dowels. Once you have also applied some glue to the holes in the front panel, join all the pieces together. Clamp the joints using clamp clips.

    Important note

    Use clamp clips to press all of the glue joints carefully until the glue has dried. Refer to the manufacturer's instructions. While pressing the joints, use pieces of scrap wood as buffer blocks to distribute the pressure evenly and avoid leaving unsightly pressure marks on the workpieces. Wipe away any excess glue immediately with a damp cloth.

    5. Fit the light fixtures

    Now lie the front section of the light box on its display side. Using a cordless screwdriver and flat head screws (2.4 x 16 mm), fit the two lower lights below the cutouts and rows of boreholes. Fit the third light in the same way above the top cutout.

    While fitting the lights, make sure that all cables are laid in the same direction. You can then guide them downwards through the opening between the perspex base and front side panel and connect them there to a triple plug. This plug is then fitted in turn to the back of the front panel. As a result, you only require one cable to supply electricity to the light object.

    6. Join the front panel and rear panel together

    You must first connect the rear panel to its (slightly narrower) sides so that these are flush with the outer edges at the front. All you need for assembly in this case are flat head screws (4 x 50 mm) since the overlapping front panel will conceal these from view. Predrill the screw holes in the rear panel. Countersink these holes so that the screw heads are flush with the surface.

    Now fix the rear panel section of the light box to the wall. To do this, use a drill and 8-mm wood drill bit to predrill the rear panel. Do not forget to countersink the holes. Make sure that the two suspension holes are at the same height.

    Copy the positions of the boreholes to the wall. Use a line finder to ensure that there are no lines or cables in that particular part of the wall.

    Depending on the wall construction, use a drill or rotary hammer and 6 mm masonry drill bit to drill holes in the wall, then extract the dust and insert the fixings. Screw in the appropriate screws with the cordless screwdriver.

    You can now slide the front section onto the rear panel structure: this job should ideally be carried out by two people. Move the front section to the correct height and screw it in place with the cordless screwdriver and flat head screws (4 x 35 mm) through the predrilled holes. Refer to the tip above about screwing together two pieces of wood.

    Tip for screwing together two pieces of wood

    In the piece where you want to insert the screws first, always predrill a hole that is 0.5 to 1 mm larger than the screw diameter; the hole should be countersunk for the screw head. In the piece that you are going to drill second, predrill a hole that is always 1 mm smaller than the screw diameter.

    Note on fixings: Nowadays, wall construction may consist of anything from dry lining walls to solid concrete walls. Therefore, first check the construction of your walls.

    Depending on how the walls are constructed, different types of fixings will be required to fit the light object.

    7. Prepare surfaces

    Take time to prepare the surfaces so they are in the best working condition possible before starting assembly.

    First, fill in any screw holes in the MDF surfaces on display using putty or wood putty. Once the putty is dry (check the manufacturer's instructions), sand the area smooth using sanding paper with a grit of 120.

    First chamfer all MDF edges with sanding paper with a grit of 120 at a 45° angle to create a small bevel. Use a sander and sanding paper (grit of 120 – 180) to work the MDF surfaces.

    8. Surface treatment

    First read the manufacturer's safety and handling instructions thoroughly. Make sure the room you are working in is well ventilated and not used for smoking, eating or drinking.
    Apply the priming filler with the roller or with a paint spraying system if necessary. Allow it to dry completely.

    You should change the paint tank if you want to apply another material with your fine spray system in the next step.

    Finely sand the primed surfaces and edges; increase the grit of the sanding paper from 180 to 220 to 240.

    MDF tips

    MDF surfaces are highly absorbent. For this reason, you may need to pay particular attention to the edges (i.e. apply several layers). You can skip the time-consuming task of sealing the absorbent surfaces by using MDF with a primer film. This MDF guarantees a perfect finish without fillers, at least on the surfaces.

    9. Paint the visible surfaces

    A wide range of paints is available, of various types and price categories. The main criteria in choosing a paint should be its workability, the technical equipment you have at home, and the surface quality and durability you require. Ask for advice at a specialist retail outlet. If you are not an experienced painter, we recommend that you practice beforehand on a sample piece.

    You will achieve the quickest and best result with acrylic paints. They are water-dilutable and are available at any DIY store in many different colours. It is particularly quick and easy to apply them using a fine spray system.

    Pour the paint into the paint tank and dilute it if necessary with water. Using a test board, adjust the spray jet at the nozzle and the paint flow at the setting wheel. The spray jet can be set to horizontal or vertical for surfaces and tapered for edges. Ideally, you should first paint the inner edges, then the outer edges and then finally the surfaces; working on these with even, parallel strokes.

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