Features of wood floor sanding

Features of wood floor sanding

Nowadays, natural building materials are very popular. After a brief peak in popularity, linoleum is leaving the scene, again giving way to laminate and wood, since wood floors are beautiful and durable, can have any shade and at the same time retain the natural pattern of the material, besides, wood is environmentally friendly and safe. Therefore, take your time to get rid of the old parquet and even the scratched plank floor..

Of course, you will have to spend more effort on putting it in order than on laying linoleum, but after repair your old wooden floor will delight you with its beauty for a long time..

Wood floor scrapping

To protect them from damage, floors are often varnished, waxed, or other protective agent that brings out the natural grain of the wood. Before this, the floor must be carefully removed from irregularities – sanded well (this process is also called scraping). Do the same when restoring old wood flooring..

In addition, slight differences in height inevitably appear when laying even new boards or parquet elements, and boards in the floor, which has been in use for more than one year, sag or shift relative to each other..

The floor should not be sanded if:

  • the gaps between its elements turn out to be more than 0.7 cm.If the gap is too large to fill it with a sealant or putty, the floor must be sorted out, replacing the damaged elements or sealing it with bars;
  • on those areas of the coating, which were walked most often, defects appeared with a depth of more than 4 mm. To loop the rest of the floor along this level, you will have to destroy most of the useful thickness of the boards (from the surface to the ridge of the castle, it has an average thickness of only 3 to 7 mm). In this case, it will be better to simply replace these areas;
  • if the fragments of the floor are swollen from the water, moldy or rotten. The structure of such a tree is damaged, it cannot be sanded, the damaged areas must also be replaced..

Grinding methods

Masters polish the floor in two ways: manual and machine.

The manual method of grinding is used mainly in small areas, since it is a very time-consuming job. Moreover, in this way it will not be possible to get a truly flat surface over the entire floor area.

The machine method is suitable for any object, but purchasing a special grinder is an expensive undertaking..

If you have a one-time job, you should consider renting it.

In order to sand the floor by hand, you will need:

  • Emery paper with a grain size of 40 to 120 units. You have to determine the amount yourself, depending on the floor area and the degree of its pollution..
  • A grater that is charged with sandpaper. Depending on the amount of work, you can use an inexpensive plastic product, or spend money on a quality one – with a wooden or rubberized handle..
  • You will also need a hand scraper – a metal plate bent at an angle of 45 degrees and fixed in a wooden or plastic handle – to clean the remnants of the old protective coating (paint, varnish) and large defects.

Grinding Machine Types

To sand the floor with a special machine, you need to imagine what type of machine you are looking for..

So, grinding machines are of the following types:

  • Drum. This is a machine for the initial rough surface treatment. The same machines are used if the floor to be sanded is made of large planks. The advantage of drum machines is that they can be used to process a large wooden floor. Its use is limited by the fact that it is very difficult to achieve perfect evenness of the processed surface when using such a machine – due to uneven grinding, even an experienced craftsman cannot withstand the entire surface at a single level. The principle of operation of the machine is that a cut of an emery tape of the required length is installed on one cylindrical shaft-drum.

Cars of this type are presented on the market quite widely in the price range from 3 to 50 thousand rubles, but the price of professional models can go up to 600 thousand. They are almost always equipped with a dust bag or can be equipped with an adapter for a construction vacuum cleaner.

  • Tape. It differs from the previous type in that the working element is an abrasive belt that rotates between two rollers. The machine can move forward by itself, but it is designed for initially flat floors – due to the long and straight working element, the recessed part of the floorboard may not be covered by the treatment.

  • Surface grinder or disc machine. In contrast to the drum, it leaves a perfectly flat, flat surface. Designed for finishing and for work from the very beginning, if you have to sand the parquet, recruited from small elements. A machine of this type is equipped with an abrasive wheel (several wheels) with a grain size of 100 to 340 units. The price of such grinders starts from 20 thousand rubles. Professional machines can be equipped with a floating system of the grinding heads, which allows you to literally polish the surface. Just like other grinders, these models can be equipped with a vacuum cleaner..

  • Curb scraper, popularly named “Boot”. It is also a disc surface grinder designed to grind surfaces around the edges of rooms, corners, steps and other areas of the floor that cannot be processed with a conventional grinder. The price for such units starts from about 9 thousand rubles.

  • Angle grinders. Devices of this type are popularly called a grinder. Equipped with a petal attachment, they can handle a fairly large amount of work. Also this class includes orbital and vibrating (working due to the translational movements of the working element) polishing machines. A grinder can be bought at a price of a thousand rubles, an orbital (eccentric) unit will cost a little more. In case you are going to restore an old plank floor, the boards in which are strongly deformed, you will need a more “serious” technique, for example, a drum looping machine.

What to look for when buying a sander?

In addition to assessing the ease of use, you should definitely look at the quality of the machine: the surface should be free of chips and irregularities. Be sure to check the reliability of the fasteners. You should also avoid using low-quality cheap sanding discs and attachments.: Breakage of moving parts of the machine during operation can result in serious injury.

Please note that it is difficult for an inexperienced craftsman to process a large floor area with a low-power domestic-class machine without height differences if he does not have a firm hand and a good eye.

In addition to these units, it is worth buying or renting a construction vacuum cleaner, abrasive wheels, belts and nozzles, scissors, plastic film, and everything else that you may need in your work..

Please, do not forget about goggles and a respirator. They must be worn while working. Finely dispersed wood dust is very insidious, so you cannot do without these products. You will also need protective gloves. To protect not only the respiratory organs, but also the body from dust, you can use a painting overalls..

In addition, you will need earplugs or earplugs to protect your hearing when using the looper..

Operating procedure

First stage: preparation of the base

First, all furniture is removed from the room and old skirting boards are dismantled. It is necessary to remove all the old protective coating: in the subsequent process of scraping it will in any case be removed, but the floor can be partially cleaned already at the preparatory stage by wiping it from varnish or mastic with a sponge moistened with white spirit.

Pay attention to fasteners sticking out of the floor – all nails or screws must be sunk into the floor to a depth of at least 2-3 mm so that they do not damage the moving parts of the grinder, which can be dangerous.

Replace any damaged planks and fix those floor elements that do not hold well, if any: this can be done with PVA glue or hardware. Carefully check the boards for loose knots, chips and gaps, if necessary, use parquet glue or special putty compounds to eliminate defects. Do not use elastic sealants before sanding. – they are not strong enough and can quickly “clog” the grinding attachment.

Please note that the sander is very dusty even with a special dust collector, so you need to close the doorways with a cloth (non-woven material), which can be moistened to more effectively trap dust, or with plastic wrap. It is better to open windows and external doors so that some of the dust can leave the room..

Stage two: initial finishing

This stage is also called scraping, as the process removes defects, dirt, old protective coatings, and so on. If the boards are made of solid pine or other coniferous wood, remove any drops of resin with mineral spirits or, for example, gasoline..

The first pass in surface grinding is most often done with the coarsest abrasive – usually 40 grit sandpaper is used. If the boards of the new floor are already smooth enough, you can skip this step and start with a finer abrasive..

If, on the contrary, you are restoring an old plank floor, the abrasive can be larger – with a grain size of 20-24 units..

The direction of movement of the machine should coincide with the direction of the wood fibers: if the floor consists of boards laid parallel to each other, then you should move in the same direction, only the first pass is made diagonally. If the parquet is laid with a herringbone, then you must also move along the diagonal of the room. If the floor planks are mounted so that the grain of the wood is directed in different directions – the sander should move crosswise, without highlighting areas.

On artistic parquet, the direction of movement is in a spiral, from the center to the edge.

The master should also consider the following points:

  • Builders advise to keep the machine’s power cord on your shoulder to avoid damage from moving parts of the machine.
  • The abrasive element must be replaced after each pass, as it wears and clogs with dust, between passes.
  • It is necessary to turn on and off the engine of the machine while driving, otherwise hard-to-remove visible marks will remain on the floor..
  • Avoid both too strong pressure and too weak, move as evenly as possible, avoiding delays, otherwise the machine may remove too much or simply burn the floor due to the fact that the working element creates a high temperature in the place of delay. Go to the next lane

  • carried out in such a way that about half of the circle (drum) is on the already processed surface (the strips will overlap, as it were).
  • Typically, four passes with 40 grit grit are followed by 60, 80 and 120 grit finer sanding passes. When processing a thin wooden floor, in order to eliminate the risk of damage to it, one pass can be excluded, for example, with abrasive number 60.
  • The corners and steps, if any, are polished by hand, using angle machines or a “boot” in the same sequence – at first with coarse, and then with nozzles with a finer grain.

  • After the completion of the initial stage, it is necessary to remove all wood dust and fine suspension – thoroughly vacuum or wipe the floor with a damp cloth.
  • Also note that the smallest wood dust, particles of putty and varnish are very flammable materials, and under certain conditions they can even ignite spontaneously, so do not allow the accumulation of wood dust and deposits of flammable building materials in the room: it is advisable to immediately remove dust and store varnishes, paints and putty in the other place.

Stage three: putty

To fill the existing gaps, defects and chips, ready-made compounds or special filler liquids are used, which are mixed with small sawdust formed during floor grinding: this trick allows the craftsmen to get a composition exactly the same color as the treated wood of the floor. Also, sometimes ordinary PVA glue is mixed with sawdust.

The mixture is applied with a stainless steel trowel – this helps in the process to cut off all small wood fibers that rise above the floor level.

After the filler has dried, the floor is again finely sanded, removing excess material.

Stage four: finishing

Do not leave the already sanded floor without a protective coating: this will lead to the fact that after a while you will have to repeat this time-consuming operation again.

Finishing is done after the putty has dried and polymerized..

Before applying varnish, thoroughly vacuum and clean the floor: even the smallest debris will be clearly visible under a layer of clear varnish.

The floor should be treated with primers containing antiseptic, antifungal agents or dyes. If you used a ready-made colored putty, the surface may be variegated, so still it is preferable to use a putty with shavings of the same wood.

After priming, the first layer of protective coating is applied – wax or varnish. For high-quality protection of the floor, it must be covered on average 5-7 coats of varnish. Depending on the operating conditions of the room, you can use acrylic, alkyd or epoxy varnish. Water-based varnishes and acrylic compounds are almost odorless, this is impossible to say about polyurethane.

To make the coating look uniform, the surface is sanded each time the coating dries with a fine-grained (more than 140 units) abrasive, and only then the last finishing layer of the protective coating is applied..

After finishing work and drying the varnish, it is recommended to wash the floor with warm water and soap so that it is not sticky..

With a sander, you can do it yourself correctly to sand the wood flooring. A grinder is a tool that you can not only buy, but also rent.

It is worth noting that sanding the floor is an activity that will take a lot of time and effort., but this is the only way to achieve a beautiful and smooth surface, which you will be pleased to walk on.

For how to grind a wooden floor yourself, see below..

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