Laying tongue and groove flooring is simple and does not take much time. If you purchased quality material, then it is enough to have some construction skills to do it yourself.

Advantages of laying tongue and groove boards

Thanks to the ideal geometry of a high-quality board, the side tongue-and-groove joints provide a reliable, sealed connection. The result is a smooth surface without gaps. In this case, the joints between the boards are practically invisible.

Tongue and groove board, dried to required humidity in special drying chambers, does not deform or warp. This floor can last for decades.

On the reverse side, the tongue and groove board has a longitudinal groove, which provides constant ventilation and prevents moisture condensation and the formation of fungus.

A tongue and groove board can be sanded many times. This allows the surface to return to its original appearance.

Laying plank floors can be produced in two ways: on logs or on a specially prepared surface. Material must be ordered with a 10% excess. This will allow the flooring to be laid freely, taking into account some curvature of the walls and leaving some for possible repairs.

Before installation, the boards must be freed from the shrink film and kept in the room for 5-7 days to equalize the humidity. This will prevent shrinkage or warping in the future.

The tongue and groove board is laid from the wall with a mandatory distance of 1.5-2 cm. This gap provides the necessary play to evenly distribute the load that inevitably arises during the operation of the floor.

• 1 Laying boards on joists

  For premises on the 1st floor, waterproofing is required. Then the logs themselves are installed from dry and antiseptic-treated timber. After their installation, the gaps are filled mineral wool for sound insulation.

  The first board is laid tongue-and-groove against the wall, maintaining a gap of 1.5 cm. It is secured with nails or self-tapping screws to each joist so that the mounting points are subsequently covered by the plinth. The following boards are fastened together with a tongue and groove connection. Self-tapping screws fix the boards to the joist obliquely through the bottom of the groove. Installation must be carried out in such a way that the joints of the boards are along the lengths of the logs. The last board is again attached to each joist with a gap of 1.5 cm from the wall.

• 2 Laying on a prepared surface

  This method is used when reducing the height of the room is undesirable. Moisture-resistant plywood is mounted on the waterproofing sheets. The tongue-and-groove board is fixed to it with self-tapping screws. The holes are closed with wooden plugs placed on glue.

Our company produces tongue and groove boards with ideal geometry. The quality of the product we offer allows us not only to carry out installation without problems, but also to obtain a magnificent and truly durable floor as a result.

The tongue and groove board is used, as a rule, for finishing the floor. It is made from solid pine or spruce. There is a tongue and groove on one edge of the tongue-and-groove board, and a groove for it on the other. This greatly simplifies the installation of the material. The boards mounted by connecting the groove and tongue form a single solid surface. After installation, the floor surface is treated (sanded and varnished) to acquire an attractive appearance and extend its service life.

There are different sizes of tongue and groove boards for ease of installation. You can find mounting units from 2 to 6 meters in length, from 9.6 to 15 cm in width and thickness in the range of 2.5-4 cm. After production, the boards are dried to 10-15% humidity and hermetically packaged. Thanks to this, you can immediately begin its installation without prior preparation.

Installation procedure

The material is laid in a certain order. You need to keep it indoors for 3 to 14 days after delivery so that the humidity in the room and the moisture in the wood are equal. The length of the aging period depends on the season of production. repair work. After a few days, you can remove the packaging film and, if necessary, cut the material to length.

After cutting, the board must be laid on logs covered with insulation or film. The material is left in this position for a few more days to acclimatize. Only after this can the material be laid.

It is not recommended to use glue or any other synthetic substances during installation. Self-tapping screws are used to secure the board. flooring screwed to each joist. The distance between the logs should not exceed 59 cm.

The first installation unit is located with the tongue-and-groove side facing the wall.

A small gap of 1-2 cm is left between them. The floor will be ventilated through this gap. In addition, if the floor's humidity increases over time and the board expands, this gap will prevent the floor surface from deforming. The boards should not be concave. You should make sure of this before starting work.

To secure it to the joists, it is best to use wood screws 5.5-6 cm long. They need to be screwed into the groove at an angle. You must first drill the holes with a drill with a diameter of 2.5 or 3 mm. Thanks to the hole, the groove will not crack when screwed in. Due to their small thickness, drills for this work break quite quickly, so it is recommended to stock up on them for future use.

The second board is attached to the first. It is unlikely that you will be able to perfectly match them to each other using a mallet, so you should not be overzealous with it. For best result you can use a wooden wedge, which you need to drive through the entire board, while screwing in the screw.

The fastest and most convenient way is to use a car jack. But in this case, it is necessary to protect the material from damage. For this purpose, small planks are used, which need to be rested against the following mounting elements. When using a jack, the use of a mallet is not required.

Thus, the installation of a floor made of tongue and groove boards is quite simple. You can install the flooring elements yourself. In this case, it is necessary to take into account the characteristics of the material.

Depending on the type of wood, tongue and groove flooring can be budget option(spruce, pine) or used in luxury interiors (oak, larch). This type of flooring increases the construction budget, but ensures a highly environmentally friendly design.

What is a tongue and groove board?

The quality and dimensions of profile lumber are regulated by the domestic standard GOST 8242. It specifies what a tongue and groove board is - this is a profiled product “Floor covering board”, marked DP or BP (floor covering block).

Rice. 2 tongue and groove board according to GOST 8242

The main requirements for a tongue and groove are:

Marking	Dimensions, cm			Wood type
	thickness	width	tongue
DP-21	2,1	6,4 – 14		coniferous and deciduous, except poplar and linden
DP-27	2,7	6,4 – 14	tongue 6 x 6 mm, groove 7 x 7 mm	coniferous and deciduous, except poplar and linden, alder, aspen only for residential premises
DP-35	3,5	6,4 – 14	tongue 6 x 9 mm, groove 7 x 10 mm	coniferous and deciduous, except poplar, linden, alder and aspen
BP-27	2,7	4 – 6	tongue 5 x 6 mm, groove 6 x 7 mm	coniferous and deciduous, except poplar and linden, alder and aspen - only for living rooms

On the groove side, the longitudinal end of the board is beveled in such a way that when connecting the lock, the lower edge does not reach the previous row by 1 mm.

End processing to ensure full fit of the ridge into the groove.

A recess on the back of the board with a depth of 2 mm (distanced 15 mm from each edge) is made only on the DP-27 and DP-35 tongue and groove. It is not on the BP-27 block and the DP-21 board. On wide lumber, it is necessary to compensate for internal stresses and ensure convection under the floor.

Important! In the building materials markets of the regions of the Russian Federation, you can find tongue and groove piles of almost any size, including those with a wedge-shaped lock, board thicknesses of 3.8 cm, 4 cm, 4.2 cm, up to 40 cm wide. This lumber is produced according to the specifications of local enterprises and GOST standards they don't match.

How to choose lumber

The choice of floor covering is significantly influenced by the installation of tongue and groove boards using existing technology. An individual developer needs to take into account the quality of lumber, size, type of wood and the method of processing it for use.

Quality

Standard laying technology involves fixing every 4-5 rows of boards to the joists with nails or self-tapping screws. Therefore, sheet piles with minor defects can be laid between them without serious consequences. The main quality parameters of a wooden floor covering are:

• humidity – 12%, in practice you can find boards packed in film chamber drying with humidity 8%;
• roughness – 500 microns for back surfaces and ends, 200 microns for painting, 120 microns for opening with varnish;
• integrity - due to the above logging conditions, a wide sheet pile (20 - 40 cm), manufactured according to the specifications of a specific manufacturer, can be assembled using technology furniture board with extensions along the length using toothed locks, boards 6 – 14 cm wide are always produced in one piece.

When purchasing certified lumber, the number of defects (wane, wormholes, knots) is controlled at the factory and complies with the permissible regulations of GOST 8242.

The grade of tongue and groove affects the quality of the interior.

Tongue pile is a profiled product for floor cladding; the raw material for its production is edged board. The manufacturer chooses the lumber grade B, A or Extra with a minimum number of defects in the wood of the floor board.

Dimensions

For most individual developers, it is preferable to lay the floor from tongue-and-groove boards with a width of 20 cm or more, the length of which completely corresponds to the size of one of the sides of the room, in order to reduce the number of longitudinal seams and not join them along the length.

Longitudinal joints in small quantities are almost invisible.

However, this is too expensive for the budget for finishing and operating the floors, since when laying solid boards cutting waste increases sharply along the length of the room; short trims cannot be used in partitions, rafter systems. Which increases the construction budget.

However, knowing how to properly fasten the tongue and groove on longitudinal joints with your own hands, you can ensure a normal coating life and a sufficient design of the floor covering. The above-mentioned GOST 8242 allows for the production of sheet piles with a length of 2.1 m, usually within 4 m for hardwood and 6 m for spruce and pine.

It is very important to choose the correct tongue thickness:

• tongue-and-groove floor board DP-21 should be laid on joists in increments of 30 cm maximum or on a continuous subfloor;
• DP-35 tongue and groove and BP-27 beam can be mounted on beams without a subfloor in increments of 60 cm maximum.

Length is less critical, since for most standard projects 4 m of products is enough without longitudinal joints.

In this case, the following nuances must be taken into account:

• perfectly straight trunks only coniferous trees, therefore, a board made of spruce and pine has a low cost compared to hardwood, whose trunks are shorter and have a natural curvature along the length;
• however, spruce and pine need to be treated more often with paints and varnishes during operation; this wood is less wear-resistant;
• from the trunks of cedar and larch, which are classified as coniferous species, long, smooth boards are obtained, by default impregnated with a natural antiseptic, possessing high wear resistance, however, they are less common and are classified as rare/valuable breeds by default;
• A tongue and groove with a wide face (the lower and upper surface of the board) has the original texture of a wood pattern, but is more susceptible to warping and drying out, therefore the service life and time between repairs of the floor covering are sharply reduced.

Laying base

Before laying any floor covering, it is necessary to provide a rigid base, the strength of which is higher facing material. This is necessary to distribute uneven operational loads on the elements of the load-bearing frame. In addition, factors to consider:

Taking into account the size and dimensions of the room, the beams should be positioned as follows:

• screed or reinforced concrete floor slab - along a short or long wall taking into account the fact that the tongue and groove spreads across these structural elements, that is, if you install the logs along the short side of the room, the length of the board may not be enough for the entire size of its long side, and longitudinal joints will appear, reducing the quality of the interior;
• overlap along beams - there is no choice of options here, the logs are always mounted at right angles to the beams, and the tongue and groove across the joists, that is, along the length of the lower beams.

The diagram of the floor pie along the beams looks like this:

• hemming - short boards or sheet material laid between beams on a tiled beam; less often a mesh is used, fixed with screws to the beam;
• waterproofing membrane – covers the sheathing and beams according to the profile cross section floor structures (diagram in the lower figure);
• insulation – basalt or glass wool, ecowool, extruded polystyrene foam, polystyrene foam;
• vapor barrier membrane - immediately on top of the thermal insulation with a continuous carpet;
• subfloor - flat board (edged or tongue-and-groove), OSB boards, chipboard, fiberboard, multilayer plywood.

Important! Instead of a subfloor, a subsystem of 5 x 10 cm boards on edge can be used as logs in increments of 0.3 - 0.6 m, if the spans between the beams are too large.

Technology of laying on logs

After preparing the base, the horizontal surface of the joist or subfloor should be level by default. The first, every fifth and last row is installed with rigid fixation to the joists. The remaining boards are simply secured with a tongue/groove lock.

Board processing

It is impossible to saturate the floor covering with special liquids after laying it from below. Therefore, the entire board should be treated before laying with the following compounds:

• fire retardant - imparting fire-resistant properties to wood;
• antiseptic – protection against rotting;
• fire bioprotection – complex impregnation containing both drugs;

When using impregnation with color, untreated areas are immediately visible.

Depending on the specific composition of the protective liquid, treatment is carried out by brush or spray.

First row

Installation begins from the wall, ensuring a 5 mm ventilated gap. Only solid tongue and groove is used without longitudinal splicing, the length of which is equal to the size of the wall. The main nuances are:

After cutting the board to length, the end should be treated with fire protection before installation.

Important! The first board must be laid with a tenon against the wall. However, a narrow baseboard may not be enough to mask the gap, so the lock is cut off along its entire length.

Next 4 rows

To reduce the finishing budget in these rows, it is allowed to use tongues joined along the length, always with ligation in adjacent rows. Installation of the treated board is carried out using tongue and groove locks, the quality is controlled visually. There should be no gaps between adjacent rows; all boards should fit snugly against the joists.

Fifth row

For rigid fixation to the joists of the next fifth row, at a distance of 3 - 5 cm behind it, clamps are attached to the joists every 1 - 1.2 m.

Possible longitudinal cracks in the flooring are eliminated due to expansion:

• between the last tongue and the clamp, two wedges are driven in on each lag alternately;
• installation is carried out using self-tapping screws in a groove at an angle of 45 - 50 degrees;
• the head of the screw is completely recessed into the wood so as not to interfere with the next ridge.

Important! Without tightening the floor covering, installation will be carried out incorrectly, and a wedge may form near the opposite wall.

If the boards are perfectly flat and have a minimum moisture content of 8%, instead of tightening, you can tap each row with a hammer. To do this, a 30 cm piece is sawn off from a solid tongue, which is enough to be attached with a tenon to the groove to provide an impact surface without deforming the locks of the floor covering.

Tapping with a hammer.

The last row

At the final stage, the installation is similar to the first row with minor additions:

• there is no need to cut the lock, since the groove is inside the tongue;
• There is not enough space to attach the clamp, so the boards are pulled together with a pry bar from the wall or a special device;
• The last board should be laid after fitting; if its width is not enough, a narrow piece is cut from a solid tongue and groove, put on it with a lock and mounted together with this board.

Important! The thickness of profiled flooring elements may vary, even within the same package. The floor surface must subsequently be treated with a grinding machine or sander.

Junction nodes

The main problems for an individual developer usually arise when covering the floor with tongue and groove in one room, and not in the entire house. A complex junction unit is the threshold. Therefore, depending on the direction of installation, the following fastening methods are used:

A door frame with a threshold solves the problem of joining floor coverings at different levels.

Advice! The baseboard is attached to the walls, not the flooring in any case.

Thus, a tongue and groove board is the easiest to self-installation flooring option. Almost all necessary tool is available in the home master's arsenal by default.

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When arranging floors in houses under construction, as well as if there is a desire or need to replace an existing and worn-out floor covering with a new one, many opt for laying a floor made of tongue and groove boards.

The secret is simple - batten made of wood has a set of excellent performance qualities:

• durability,
• environmental friendliness,
• strength.

Only wood materials create a unique microclimate in your own home, which promotes health improvement human body.

Laying floorboards can be a bit of a hassle. But, if you do everything strictly following the instructions technological process, the job will be completed successfully, and the tongue and groove floor will last a very long time.

Bases mounted under the floorboard

The tongue and groove board is laid on any surface. These could be:

Insulation and waterproofing of floorboard coverings

Insulation is usually carried out if the room is on the ground floor, and there is no heated space underneath. ground floor. Fiberglass or basalt wool is usually used as thermal insulation laid between the joists.

Important! In addition to the fact that the insulation is laid on both sides with vapor-tight waterproofing, a 5-centimeter gap must be left between it and the lower surface of the floor for ventilation and removal of excess moisture.

The choice of wood type for the future flooring is determined by both the aesthetic needs of the owner and his material capabilities.

One of the most valuable, both literally and figuratively, is a floor made of tongue-and-groove boards of Siberian larch or oak. The strength, and therefore durability, of these wood species is very high. Floors made of spruce, pine, alder, aspen, and fir are softer and, accordingly, have a short service life.

When choosing the grade of flooring material, you need to take into account what kind of final finishing will be carried out. If you plan to paint the floor, then there is no need to take the highest or first grade material. And if coated with varnish, it will not be superfluous. The varnish will emphasize its beautiful textured pattern, unencumbered by the defects inherent in more low grades.

The larch floorboard is produced tongue and groove, i.e. on one side it has a protrusion (tenon), and in the other side surface a groove is cut out with a milling cutter - a recess (groove). During installation, the tenon of one board fits into the groove of the adjacent one. This results in a smooth, level floor.

Advice! The direction of laying the floorboards must be chosen parallel luminous flux from the windows. In corridors it is better to place them as you move.

Do not forget about the gap between the coating and the walls of 10-20 mm, which closes perfectly floor plinth.

Do-it-yourself tongue-and-groove flooring

1. To reliably seal the boards, we place the first of them with a tenon against the wall.
2. We combine the next one by connecting the groove and tenon with the previous one.
3. It is better to fasten with self-tapping screws (since nails rust), usually with six or seven. Let's consider two ways:

• The self-tapping screw is screwed into the groove at an angle of 45⁰. Sometimes dry material may crack. In this case, the fastening point must be drilled with a drill of the same diameter as the self-tapping screw;
• in the second case, we screw in the self-tapping screw from above, deepening it a little, so that we can fill it later.

1. If necessary, cut the end board to length in order to obtain the desired width, taking into account the gap between it and the wall. Fasten the tongue and groove board in any convenient way, because the attachment point will be covered with a plinth.
2. Having completed the installation, the tongue-and-groove floorboard is sanded and then varnished or painted at the request of the owners.

Flooring actually completes the construction of a new home and, in many cases, the finishing of an old one. Until this work is completed, the rooms cannot be considered complete. In living rooms, unlike utility rooms, it is recommended to use a tongue and groove board, but it must be used skillfully, strictly following the rules. They concern both the styling itself and its choice.

Peculiarities

The tongue and groove board is equipped with a longitudinal one-sided groove. A tenon is placed on the opposite side, which should be buried in the groove of the adjacent board when laying. This move ensures that the product will last a long time and will not blow out. Even a deck board cannot have such high performance. The products are carefully adjusted according to geometric parameters, the side parts are cut off, and the front sides are thoroughly polished.

Tongue and groove boards, thanks to the channels on the conventionally lower side, are well ventilated. The formation of tenons and grooves on the sides allows you to limit yourself to a smaller amount of sanding than when using edged boards. The tongue and groove option is quite beautiful, reliable in operation and mechanically strong. However, all these advantages are achieved only under one condition - with proper selection of materials.

Materials

Oak, larch and pine are of key importance in practice. Pine flooring is relatively cheap, but its softness results in a high risk of deformation. As a result, in areas where people walk more often, “paths” appear after a while.

The situation can be corrected by using a low-wear varnish, which covers the floor in two layers.

The larch option is much more expensive, but the cost is fully justified by the increased durability of the floor and the ability to use boards without covering them with anything additional. Most often, larch is impregnated with oil solutions, which avoid the formation of hard films on the surface. Ash and oak tongue and groove boards are considered elite types of flooring, but visual beauty, exceptional density and minimal wear turn around increased buyer costs. It is extremely rare that such floors are covered with additional layers, since their natural aesthetics are enough to solve the problem.

It is necessary that the wood was always dry(dried in a special technological chamber). When sawing, it is not allowed to increase the humidity to more than 15%. Please note that such techniques greatly increase the cost of tongue-and-groove boards compared to the natural drying method, and even less waiting does not reduce product prices. One way or another, humidity control is carried out with a special device.

Boards dried in chambers are supplied wrapped in polyethylene, so they will not be able to absorb moisture from the air. The simplest test is sound: a damp board always gives a muffled echo when it is tapped, but a properly dried board always makes a ringing sound. If you place wood that is too wet, after it dries you will notice cracks, and the service life of the coating will not exceed six months. Drying elements will crack and may even twist, and the only way to counteract this is to press the boards tighter.

Dimensions

The optimal thickness of a tongue and groove board is 0.07-0.2 m, and it is important to pay attention to its width. An overly narrow coating is difficult to install, while a very wide one may lift up at the edges when it dries. As a result of uplifts, “ribs” and irregularities appear.

Sanding can eliminate this problem, but requires increased costs and additional time.

Typical lengths are 300 and 600 cm, although if you wish, you can purchase a board 4 meters or 5 m long. In any case, designs that are slightly shorter in length than the room as a whole are preferable. Grooved products with a thickness of 21, 35, 50 mm are often found on sale. remember, that For the manufacture of floors, only coatings no thinner than 2.7 cm are applicable.(moreover, the minimum value is suitable only for utility rooms, and in a living room the use of a coating of 3.5 cm or more is justified).

How to choose?

The industry produces several varietal groups floor boards. Thus, the Extra category simply cannot have defects, even the most insignificant ones. IN normal conditions Group A products that are only occasionally stained are quite sufficient, and you will not find other deviations from the norm even with a close inspection.

Marking B shows that the boards certainly have inhomogeneities; they contain not only spots, but also knots. Finally, group C may sometimes contain through grooves after knots fall out and deformations that are not standardized in size. The last category is not suitable for finishing layers, but rough laying is quite possible for it, it even helps to save a lot of money.

Never rely on GOST markings, but carefully measure all parameters - they must be equal in each product and even in its individual parts. Detecting curvature is not difficult if you know what to look for.

The groove should be slightly deeper than the tongue, then there will be no need for additional processing. When buying tongue and groove boards for an apartment or for a house, evaluate the distance from their top edge to the connecting parts. If there is a discrepancy, you will either have to put up with the unevenness after laying various elements, or specially sand the wood. Of course, all this should be monitored in production, but we must take into account that the error can be large, and it is better to immediately be prepared for additional work or refuse the purchase.

It is advisable to focus not only on reviews, but also on such an important characteristic as sawing wood. If it is classic, we can assume that the requirements of the state standard are fully met. The heaviest, thickest boards can only be obtained by splicing together. Of course, this technique allows you to achieve any desired length of the structure.

Judging by the comments of those who have previously laid tongue and groove flooring, this is a fairly reliable and stable structure. An indispensable requirement when using it in bathrooms and other damp areas is use of larch (other types of wood are absolutely not suitable).

How to install?

To avoid the negative effects of drying out, the work is done in two stages. At first, only one bar is placed every four numbers. When 6 months have passed, the flooring needs to be sorted out, the cracks closed and all the material laid. remember, that The tongue and groove board in living rooms does not just dry out, it is mechanically deformed. And that’s why the first time it is placed with the reverse side up, and the second time it is turned over to its normal position. This technique allows you to make the coating clean, dry and completely reliable.

Always buy a certain number of boards in excess of the estimated need, they will come in handy if there is free space left when the flooring is pulled together. 2 or 3 elements will need to be added after drying. They should always be stored in the same room where the flooring will be installed. Otherwise appearance turns out to be much worse than expected.

The standard fastening is with nails, sometimes self-tapping screws are used. Take a nail made of flexible steel grades that can withstand significant loads. Even if the board is bent, the fasteners will not break. But hammer them in carefully, carefully monitoring the result. After all, it is very difficult to remove such a nail without breaking the floor covering itself.

Crooked boards cannot be replaced without removing the fasteners; they must also be removed when rebuilding a drying floor. To encounter a minimum of problems, use self-tapping screws, and only yellow ones, and not black ones.

You can fasten a tongue-and-groove board with your own hands “in the face” - this is a very reliable method, but not very elegant. The fasteners are driven into the front side of the board, a pair of screws are used on each side, a distance of 50 mm should be maintained from the border. If you attach it to a groove (by screwing the screw into the lower part of the groove at an angle of 45 degrees), the cap will have to be driven deeper into the tree. Only this condition will allow you to safely install the next boards. The disadvantage of this generally simple approach is that risk of boards splitting if they become twisted.

Laying “in tongue” means that the self-tapping screw captures 2/3 of the board thickness, but you will have to check that the tongue remains intact. The hidden fastening is carried out in such a way that the self-tapping screw does not interfere with the installation of subsequent blocks; the hole is prepared in advance, and the drill is taken of the same diameter as the fastener head. The most commonly used screws are 0.45 cm in girth and 7.5 cm in length.

You can lay tongue-and-groove wooden products either on logs or on special supports (which will raise the top layer of the floor 7 cm above the base). But if the room is low ceilings, you will have to put plywood there so as not to absorb too much of the height. Support beams are used when the subfloor is too uneven. The thickness of each beam is at least 10 cm.

By laying the boards at right angles to the joists, the usual pitch of the structure is 0.6 m, and if the angle is smaller, then the span is proportionally reduced. Never fill the gap separating the joists from the ground, otherwise ventilation will be impaired. Helps to avoid unnecessary noise when walking on the floor laying a soundproofing layer. In all living rooms, any beam must be directed at right angles to the window, and in corridors - parallel to the direction of movement.

When choosing plywood, make sure that it is no thinner than 1.8 cm, otherwise the boards can easily deform under the most normal loads.

The work begins by checking the plane of the surface on which the plywood will be laid, and if it is not level enough, the problems are immediately eliminated. The sheet is divided into strictly identical fragments, then the blanks are laid out on the floor, placing them diagonally to the boards and attached using dowels. Move the plywood pieces away by 0.2-0.3 cm and leave a gap of 1.5 cm to the wall (this is necessary to compensate for thermal expansion).

The surface layer must be passed through with a grinding device or a grinding attachment on a drill. Minor imperfections and roughness are removed manually with sandpaper category P24 or P36.