DM boards

DM boards have been one of the most used materials for many years, together with chipboard panels, for the manufacture of all types of indoor furniture.

It is a multipurpose material, with some excellent characteristics and a quality / price ratio much higher than that of other alternative products.

What are DM boards?

What is DM? These acronyms refer to medium density fiberboard. In Anglo-Saxon countries, they are called MDF (Medium density fiber board) In others, it is common to refer to them with the name of the most popular brand or with the largest market share. For example Trupán, Fibrofacil

Medium density plates are a combination of wood fibers (about 85%) and adhesives pressed and subjected to high pressure. The fibers are obtained by breaking up the wood by thermo-mechanical processes. In the case of adhesives, urea-formaldehyde glues are mainly used. The proportions in which these components are used depend on the desired result or the type of DM being manufactured.

This process forces the wood to pass through metal rolls that turn it into threads during drying, reducing moisture by up to 20%. Wood is not necessarily used exclusively, bark, carbon fiber, bamboo, etc. can be used.

In addition, other components can be added to add additional properties to the product. For example, improve your resistance to fire, water or simply to dye it.

If we had to give a quick and easy definition, we could say that an MDF board is basically chipboard.

What woods are used?

Mainly used are coniferous woods, such as pines or firs. Contrary to what happens with agglomerates, the use of leftovers from the timber industry or recycled wood is much less common.

DM plate characteristics

  • Homogeneous and smooth surface, much more than a chipboard card. Ideal for the application of all types of finishes, veneer and cover with melamine, high pressure laminates (HPL) …
  • It has no grains, knots or rings like wood.
  • It is marketed in a wide variety of formats, sizes and thicknesses.
  • Flexural strength. The values ​​vary depending on the density of the plate. About 29 (+/- 3) N / m2 for a thickness of 9 mm and 23 (+/- 3) N / m2 for a thickness of 9 millimeters.
  • Resistance to traction. Between 0.7 and 0.8 N / m2.
  • Density 600-700 kg / m3.
  • Workability. Excellent performance. It can be milled, machined and bent (within logical parameters). It can present some problems if we use hardware close to the edges. Pre-drilling is recommended. It has very good behavior when using adhesives and glues.
  • Availability. Although it is not difficult to find crude fiber boards, it is much easier to find them coated with melamine, wood veneers, varnishes, etc.
  • It is widely accepted that fiber boards have a higher resistance to moisture than other boards, however, this need not be true. O moisture resistance is widely defined by adhesives or other chemicals used during the manufacturing process. Therefore, if we are looking for a fiberboard with better moisture resistance, we must demand that it be waterproof.
  • There are other possible treatments to apply: fungicides to prevent the growth of fungi, or hardeners are other valuable examples of the versatility of this type of technical or industrial wood.
  • Has a relatively low price if we compare with the alternatives in solid wood or plywood, but superior to the chipboard.

Disadvantages and Disadvantages of DM boards Wood

  • Limited moisture resistance. Its use should be limited to humid environments and never in direct contact with water. The type of DM Water Repellent plate improves its behavior against moisture but does not leave it far from immune.
  • Toxicity. As already mentioned, adhesives and / or glues, mainly urea-formaldehyde, are used to manufacture this type of DM sheets. This can pose a health risk. Depending on the quantity and emission of formaldehyde, we can classify them as E-1 and E-2, the first being the one with the lowest emission and accepted by the regulations in force. It should be noted that most manufacturers currently classify their products as low in formaldehyde. It is, therefore, a remission problem.
  • The edges represent the weak point:
    • Less resistance to impacts.
    • Screws or nails close to the edge represent less support due to the fragility of the area.
    • Greater water / moisture absorption. In the case of melamine MDF boards with edges, the small spaces that can remain when the edge is glued, even if they are not visible to the naked eye, can allow the passage of water.

Types of medium density fiberboard

There are different ways to classify MDF boards.

According to yours composition:

  • Pattern.
  • Waterproof DM. The composition of the card is modified to improve its behavior against moisture. Water-repellent additives are added to the resins that are used in this case as binders, which slows down and slows the progress and effects of moisture to some extent. This does not in any way mean that water-repellent MDF boards are suitable for contact with water.
  • Flame retardant DM. In that case, retardant or fire retardant additives are added. This makes it possible not to make them, much less fireproof, but to delay the action of fire. As a rule, they should be classified according to the degree of fire resistance. The reason for this is that building regulations, depending on use or installation location, may require a specific level.
types of veneers dm

It is common for water resistant dm has a green tint and red fire resistant dm. This is because dyes are applied during the manufacturing process to differentiate them easily. It is a common practice, but not essential.

In function of density. The following values ​​are approximate.

  • Light or low density. Densities less than 500 kg / m3. The low weight makes it ideal for light applications: doors, decorative structures …
  • Average density. Intermediate densities, normally between 600 and 700 kg / m³. It is the most common type.
  • High density or HDF. Densities greater than 850 kg / m3. Higher density means not only more weight, but also more strength and stability. We are, therefore, facing a plate that could be used in more demanding environments and even with some humidity. Never in direct contact with water. It is mainly used in the manufacture of countertops, laminate floors …

From a strict point of view, we can only talk about DM Board when we talk about average density. However, the concept has become widespread and, although it sounds strange, it is more common to find a consumer who asks for a low or high density DM board than another who asks for a high density fiber board, which would be more correct.

Coated or uncoated:

  • Uncoated or raw. This type of MDF is much more commercialized than the chipboard equivalent. It is intended largely as a surface for applying finishes: lacquer, paint, varnish, veneer …
  • Melamine. Melamine is a common finish for all types of slabs, not just for DM. It offers a non-porous, resistant surface and the possibility of reaching almost any design, color or texture. It is also very economical and greatly simplifies the work of the professional, since it eliminates the need to perform tasks related to finishing (sanding, painting …).
  • Substituted. In this case, the boards are covered with natural wood veneers of “noble” species. Thanks to this, a board is obtained that does not imitate natural wood, in a sense. It has the same touch, smell, etc. It can even be sanded and finished. They are sold with or without the finish already applied (usually varnish).

Special Types. As we already said, this is a very versatile product that can be used and manufactured in different ways. Some less common types, but that we can find, are:

  • Dyed. During the manufacturing process, dyes are added to obtain the desired color.
  • DM for frames. They have a higher percentage of adhesive.
  • DM for printers. Also with a higher proportion of adhesive to gain stability and decrease the amount of ink absorbed by the plate.

Fiber board dimensions

The MDF board is probably the one that is most commercialized in sizes and thicknesses. To which should be added the customized orders, that is, those made at the factory with specific measures.

Most common measures: 244 × 122, 285 × 210 and 366 × 210 centimeters.

Most common thicknesses: 3, 5, 9, 10, 12, 16, 18, 25, 30 millimeters.

Density: How much does a DM boards weigh?

As already mentioned, fiber boards with different densities can be manufactured, the most common being the average density, with values ​​that can be approximately between 600-700 kg /3.

This density varies depending on several factors. The manufacturer’s purpose, thickness, etc.

As a guideline, the weights are:

  • Plate measuring 244 × 122 cm and 5 mm thick: 12 kg.
  • Board 244 × 122 cm and 16 mm thick: 36 kg.
  • Plate measuring 244 × 122 centimeters and thickness 30 mm: 64 kg.

It should also be noted that the density is not uniform across the board. The interior always has a little less density than the external faces.

Prices of medium density boards

As we already mentioned, MDF boards are cheap, especially if we compare them with other types, such as HPL, plywood, etc. Whose prices multiply those of DM.

The price differences between the most common types, raw MS and melamine, are minimal. However, when lacquers, veneers of natural wood or other less common characteristics are included, the price increases considerably.

For example:

  • DM 244 × 122 cm without standard coating and 16 mm thick costs € 18-25.
  • The DM 244 × 122 cm uncoated water repellent and 16 mm thick costs € 30-40.
  • The standard white melamine DM 244 × 122 cm and 16 mm thick costs € 20-30.
  • Waterproof white melamine DM 244 × 122 cm and 16 mm thick costs € 35-45.

Uses of DM boards

dm uses

dm boards uses

All sorts of furniture, except for outdoor furniture or where it must withstand excessive loads. For example:

  • Cabinets and shelves.
  • Modulation and kitchen doors.
  • Living room furniture.
  • Bathroom furniture.
  • Office furniture.

It is undoubtedly one of the best materials for finishing application: paints, lacquers and even varnishes.

Wall and ceiling coverings.

Carvings, sculptures and other decorative or artistic elements.

Floor support: laminate, multilayer … In this case, it mainly uses the high density version.

Interior joinery: baseboards or baseboards, flashings or jambs, doors, fittings

It is perfectly suited for working with numerical control (CNC) machines.

They are not suitable for outdoor use or for direct contact with water.

Why is it so good to apply finishes?

As already mentioned, it is a type of industrial material basically composed of wood. This DM wood is decomposed into fibers and then pressed. The result is a much smoother and more uniform surface of which any wood naturally offers.

Even types of DM are sold with higher proportions of glues or adhesives and higher surface density to reduce product absorption, which means significant cost savings for painters, lacquers or any other type of professional.

You can easily be varnished, painted (enamels), DM varnished …