Technology of making Flush Doors.

    Flush doors are the unique choice for almost all types of buildings - residential, commercial, institutional, high-rise and other construction and architectural buildings.  The details given in this page are designed to help you decide the right choice that meets your needs and tastes. 
    Broadly, there are two kinds of flush doors - the hollow core door with a timber frame covered over with plywood / hardboard and the solid core door.  The latter may have either a large number of timber reapers, or a single particle board forming the core. We at Madras Chipboard Ltd., have chosen solid particle board as the core for our LAXMI FLUSH DOOR in view of its strength, sturdiness and durability.

Technical Details :

            CORE
            FRAMES
            ASSEMBLY

Customers' Choice:

            Face Veneers
            Lipping
            Double Shutter
            Single Door with Vision Hole
            Plastic Coating
            Special Shapes
           
CORE:        

Particle boards are manufactured with selected species of soft and medium hard wood particles: the particles are dried, graded and mixed with Phenol / Urea Formaldehyde resin and pressed at high temperature and pressured into boards of required thickness.  As the particles are carefully graded and glued together with thermosetting resin, there are no voids to harbour insects and fungal.  This treatment makes our flush doors anti-bore and anti-termite. Since the particles are random-oriented, the finished board has almost equal strength in all directions compared to ordinary timber, whose strength values along and across the grains are vastly different.   The particle board is available in sizes much larger than what is normally feasible with natural timbers.  

FRAMES:

The framework of the shutter is made out of natural timber. The normal width of a flush door frame is 85mm wide with the thickness specified by the customer that fits the thickness of the finished flush door. Suitable species of medium-hardwood sizes are selected and impregnated with specific chemical preservatives using the latest Full-cell Vacuum Process ti minimize insect attack. The sizes are then seasoned to stable moisture levels in the Kiln-Seasoning Process: natural timber may have from 35 to 150% moisture. Such high moisture contents lead to warping and cracking of the timber when the surrounding air becomes dry, and bulging when the humidity increases. Once the timber is seasoned to its stable moisture level - 8 to 10% depending upon the species - it becomes immune to the changes in the atmospheric humidity.

ASSEMBLY:

The treated timber frames are assembled together with special fasteners, the particle board core is laid within and fastened to the frames; the entire assembly is covered with cross band veneers on both sides (parallel to the width of the door) followed by face veneers (parallel to the height) thus making a 5-ply construction (core +2 cross bank +2 face veneers) for unmatched strength and sturdiness. Boiling water proof Phenol
Formaldehyde thermo-setting resin is used for gluing the veneers to the door to ensure durability. The door is then hot-pressed in special hydraulic presses at 130 C - 140 C and 200 - 220 psi. Normal finished thickness
of doors may be 19,25,30 and 38 mm.

Customers' Choice:

Face Veneers: Depending on the proposed final finish, the face veneers may be commercial (for painting) or decorative (for polishing); Doors/Boards can even have one side commercial and the other side decorative. While
Teak veneers are widely used as decorative face veneers, other veneers such as Rosewood, Mahogany, Walnut etc., can also be made for special bulk orders.

Lipping: Teak or similar hardwood reapers, fixed to some or all the edges of the flush door are called 'Lipping' their intended function being to enhance screw-holding capacity and to protect the door against moisture ingress. The lipping may be external (visible as a beading around the door) or internal (covered over by the face veneer). The external lipping is usually not more than 8mm wide and is screwed to the door, while the internal lipping is about 23mm wide and glued to the door with thermosetting resins and hot-pressed. Any planing at site at the time of mounting the door will have to be well within these limits. It may be noted that chemical-impregnated and kiln-seasoned shutter frames of the flush door have adequate screw holding capacity and give ample protection against moisture.

External Lipping an illustration:


Internal Lipping an Illustration:



Double Shutter: For wide door, the shutter may be made in two leaves, either equal or unequal; this should be specified clearly in the Purchase Order, stating the width of the door in the closed position as well as the
width of each leaf if they are unequal. For such doors, we can provide rebate-cutting if required; the swing of the door - Right hand inside opening or Left hand inside opening - must be specified in the Purchase Order.






Vison panels and Louvers:

If specified in the Purchase Order, we will provide cut-outs in the shutter with trimming reapers around for fixing vision panels or louvers: the size of the cut-out required along with the height above the bottom of the door to the bottom of the panel/louver should be clearly stated, preferably with a rough sketch.



Plastic coating: The finished door may be given a coat of Phenol Formaldehyde all over: the trade believes that such a coating improves the weather-resistance of the door, making it External Grade suitable for use in
special locations like bathrooms.

Special Shapes: Being an engineered product, the flush door need not always be rectangular: it can be made into any shape as per the wishes of the client. However, the arch shape with a curved top style is very much in
vogue. Here again, the exact should be specified.

Flush doors have become an inseparable part of our daily life. Now that you have a fair idea of the way the flush doors are made and the various possibilities available, we hope you would be better-equipped to make the
right choice.

We, at MADRAS CHIPBOARD LTD., have over three decades of experience in manufacturing high quality LAXMI FLUSH DOOR. We keep ourselves always abreast (if not ahead) of the rapid developments taking place in this field, so that we may continue to provide our valued clientele with State-of-Art products that are good value for money.

See Gallery to view the designs of Laxmi Flush Doors.

To know more and to place your orders, please Contact us.