How to sand wood with sandpaper. How to sand wood properly - woodworking. Priming and topcoating
Solid wood materials must be carefully processed: sanding the saw cuts, removing glue residue, treating the places where the chips stick out, sanding the wood fibers that protrude strongly. These procedures are performed before varnishing or staining the surface. Even from veneer or plywood, the lining is initially thoroughly sanded. Only in extreme cases can be left as is. All procedures for sawing wood leave roughness on the surface; when grinding, these irregularities become much more noticeable. Both primary and secondary machining, and good tools used in this, do not guarantee a completely flat surface.
Sanding with an eccentric sander
Sanding wood surfaces
Pay attention to the material with which smooth surfaces are polished. For example, sandpaper: it should not be rough, in this case it will only scratch the wood. A skin without bosses is also not suitable for such procedures, it will unevenly treat the surface. But the bosses contribute to an even fit of the skin to the wooden surface over large areas. A cork boss is best for sanding wood. However, an ordinary block of wood with even edges is quite suitable. For convenience, they often use holders specially designed for sandpaper or a wooden block. Such holders are made of plastic or hard rubber, consisting of several parts - the lower and upper, between which the sandpaper is installed.
To clean a rough cut from a saw, a sandpaper with an abrasive coarse-grained coating is used, with a grain size of at least 100. But planed surfaces are better processed with a sandpaper with a grain size of more than 120. At the end of grinding, skins are used, the grain size of which is not more than 240. For high-quality and easy grinding, they make smooth movements , without any extra effort and perform grinding in the direction of growth of wood fibers. Good masters do not make sandpaper processing long, they do it easily, with almost no pressure. If the sanding process is done correctly, the wood surface becomes smooth, and the tiny, protruding fibers are not cut off, but pressed against the surface.
For grinding, special devices - "sand plates" can also be used. They are, like sandpaper, different grain sizes and different sizes. They are "sand plates" steel elements with sharp edges and protruding small "pins". Due to a certain distance between the "pins" when processing wood surfaces, a lot of sawdust appears, while the edges remain quite sharp for a long time. There is really one nuance to such a device, it is much rougher than a simple sandpaper.
About sizes. When processing the surfaces of large parts, it is more profitable to use a boss wrapped in sandpaper, but when grinding small elements, they do it differently: a piece of skin of suitable sizes is attached with strips of adhesive tape on a workbench and the part itself is driven along the skin. Thanks to this technique, rounding at the edges is avoided. After complete grinding, it is necessary to remove dust particles from the surface and only after that proceed with further processing.
Planing wood surfaces
Now the goal is to bring the surface of the wood to a state of impeccable smoothness and evenness without a single notch. Planing is very rarely used to give some form to the workpiece. When performing this task, a jointer, planer and sherhebel are used. In structure, these three tools are very similar: a sharp knife and a wooden case. Knives can be of various shapes, widths and differ in device. Usually the knife is fixed with a screw or wedge.
The first rough planing is performed using a sherhebel. The edge of his knife is usually rounded, and the width of the knife is about 3.5 cm. With this tool, narrow, thick chips are removed from the surface of the tree, after which almost identical grooves remain on the surface.
Further work is carried out by a planer. It is equipped with a knife with a thickness of 5 cm, or even more with a cutting straight edge. They can be double or single. The latter have a special pad that has the ability to remove the chips being removed. The surface processed by a planer with a double knife comes out much better. The length of this tool is about 25 cm. The planer removes a thin, even layer of chips.
A jointer or semi-joiner is used to process large surfaces. Planed board for example. Such tools are usually 50 or even 80 cm long. If the work is very complex and requires certain skills, tools such as zenzubel, face planer, tongue and groove, selector, folded belt, etc. are used.
Tools for planing wooden surfaces can be not only with a wooden case, but also with a metal one. They are not much different, usually they are chosen, relying on their own tastes.
You will need
- - cycle;
- - whetstone;
- - water;
- - a spray bottle or sponge;
- - primer for wood;
- - flat brush;
- - sandpaper (P100, P120, P180, P240);
- - holder for sandpaper or boss, bar;
- - double sided tape;
- - round stick;
- - sanding sponge
Instruction
Raise the workpiece against a light source and carefully examine any irregularities. Also in the future you will be able to control the quality of your work. If you see small grooves from the planer and protruding fibers on the planed part, you need to scrape the wood.
Pick up a scraper (metal tool with a cutting edge) that is well-sharpened at a 90-degree angle. Take it with two, put it at an angle and start moving in the direction of the wood fibers. Thus it is possible to align solid wood, veneer and plywood. Chipboards (chipboards) are not recommended for scraping - they quickly dull the tool. In the process of work, check the sharpening of the cycle and correct it on the whetstone.
Moisten the surface of the workpiece with warm, clean water and a foam sponge. You can use a spray bottle. After the part dries, some of the dents on it will disappear, and the wood fibers will rise.
Apply a diluted wood primer to the surface to be treated - this will speed up the sanding process. Work with a flat brush with soft bristles. The optimal conditions for high-quality priming are a cool, dry room in which there is no access to a large amount of dust. Let the product dry for an hour.
Start leveling the wood first with coarse sandpaper, then gradually switch to finer abrasive. Treat rough cuts with a hacksaw with a coarse-grained sandpaper (marking P100); planed surfaces - with P120 abrasive. For finishing sanding, first use sandpaper P180, then - P240.
In order for the abrasive to adhere evenly to even surfaces, it is recommended to use special holders for sandpaper - plastic or hard rubber. You can wrap the sheet around a cork boss or bar with smooth edges.
It is necessary to grind the wooden part only in the direction of the wood fibers. Do not press too hard on the working tool - otherwise you can achieve the opposite effect and scratch the workpiece. If you need to process a small detail, attach a piece of sandpaper to the workbench with double-sided tape and carefully run the desired part of the product over the abrasive.
Be especially careful when sanding surfaces of complex shapes: profiles, curves, grooves, small roundings. Place a sheet of sandpaper between two fingers, or stick a strip of abrasive on a thin stick. For processing roundings, you can buy a sanding sponge with a soft elastic lining - it must completely fit the area to be treated.
Easily grind the edges of the transitions from the frontal plane of the part to the end. Smooth out the ends, moving from the middle to the edges. This will be the final stage of grinding the wooden blank. You just have to carefully clean the surface of sanding dust.
Sanding a wooden floor is used to obtain a perfectly flat surface of parquet or plank flooring. Moreover, this technology is used for both old and new flooring. In the first case, renovation or renewal is carried out, in the second - alignment and preparation for finishing with protective agents: varnish, oil, wax.
Any wooden floor is assembled from many elements. In the process of laying new parquet slabs or large-format lamellas, it is very difficult to achieve a perfectly even surface. The most common occurrence is drops, minor defects, scratches, areas with sapwood.
Almost the same set of problems is found in the old flooring, which has been in operation for more than one year. Polishing a wooden floor is called upon to eliminate all these shortcomings, the essence of which is the polishing of wood and the preparation of its surface for varnish, oil, wax or any other decorative and protective agent.
Thus, the goals of grinding:
- floor leveling;
- Elimination of surface defects;
- Removal of old paintwork, dirt.
Renovation of an old wooden floor.
Sanding a wood floor correctly is not an easy task. To do this, a number of hand tools or electrical units are used. But the secret to good work is to gradually reduce the grit size of the sanding head. That is, first of all, rough processing is carried out with a sandpaper with a grain of 40-60 units, then fine - 100-120, 140-180 units. Compliance with this simple rule will allow you to achieve excellent results even in difficult cases. For example, if the wooden deck has multiple surface damage or differences between the planks of more than 3 mm.
sanding the floor no need in the following cases:
How to sand wood floors
The processing of a new wood coating and the restoration of an old one begins with the question: which tool to choose? Focus on two basic conditions - the scope of work and financial capabilities.
Masters perform grinding in two ways:
To grind a wooden floor by hand, you will need:
With manual, as well as machine grinding, it is advisable not to forget about personal protection - a respirator mask and protective goggles.
For fast and high-quality preparation of wooden floors, the machine method is most often used. In this case, the following types of electrical equipment are used:
- Belt or drum type grinder.
This is a complex unit for pre-sanding and rough grinding of boards or small-format parquet slabs. Abrasive grit - from 40 to 80 units. The difference between the tape and drum apparatus is small. For the first, an abrasive skin cutting belt is used, which moves between two moving rollers. The second uses a piece of sanding tape glued to a certain size of the drum, which is mounted on a cylindrical shaft.
It should be noted that grinders of this category are produced in a rich assortment: professional and standard, with a single-phase connection for 220 V or three-phase for 380 V, with an integrated dust bag or an adapter for connecting a construction vacuum cleaner, etc. The cost varies widely: household appliances can be purchased on average for 3,000 - 50,000 rubles, the price of professional ones reaches 600,000 rubles.
- Surface grinder.
A single-disk with a mono nozzle made of sandpaper or a three-disk, equipped with 3 abrasive wheels with a grain size of 100 to 340 units is produced.
This type of product is designed for the finest, literally jewelry finish grinding of wood and cork surfaces. It is also used for intermediate leveling of varnish. Single-disk devices are simpler, but three-disk devices are interesting in that each element rotates around its own axis, and all three revolve around one common center.
Professional units are also equipped with a system of floating sanding attachments, which, combined with multidirectional rotation, allows you to work out the surface to a mirror-like smoothness and evenness. The price of grinding machines is from 20,000 to 220,000 rubles.
- Surface grinding single-disk machine of the "boot" type.
Designed for sanding wooden surfaces in hard-to-reach places, such as under radiators or on stairs, in corners or along walls. Abrasive grain size modulus – from 40 to 320 units. Both household and professional devices are equipped with convenient rotary handles, the ability to connect vacuum cleaners or dust collectors. The price starts from 9,000 rubles.
Surface grinders "boot".
- Angle grinders.
Includes grinders, vibration and eccentric (orbital) polishers. In the same group can be attributed small tape units of a household type. Recommended for rough and fine processing of wooden surfaces. Convenient for working in hard-to-reach places and small areas. Some products are equipped with a motor speed or power controller, as well as a kind of adapter for connecting a vacuum cleaner or dust collector.
The cheapest are vibrators. Their cost varies from 1000 to 35000 rubles. Bulgarians can be purchased for household, semi-professional and professional at prices ranging from 1,500 to 70,000 rubles. Orbital machines will cost a little more - from 3,000 to 90,000 rubles.
In a good way, in addition to the above units, you need to purchase or rent a construction vacuum cleaner in advance and buy a whole set of components. Including abrasive wheels, tapes or nozzles of various grits (preferably from 40 to 240 units), scissors, etc.
What is the best grinder to choose? There is no exact answer to this question, but it is worth paying attention to the main parameters:
Purpose and product class
Household products are characterized by low weight, low price and compact size. But they are intended for one-time or rare work. Power - no more than 1 kW. In addition, the width or diameter of the useful surface rarely exceeds 15 cm. It is difficult for an inexperienced master to work evenly over large areas with them - you need a good eye and a steady hand.
The professional series are large-sized and heavy devices with a working width of up to 30 cm or a diameter of up to 60 cm. There is good thermal protection, a special kit for quick change of nozzles, as well as various tread elements - RCDs, limiters, speed switches, rotary ergonomic handles, etc. The average power consumption of a grinder is about 2-2.5 kW.
Grinder for the pros.
Build quality
Pay attention not only to the ease of use, but also to the quality of the details. The machine must have a flat surface, without chips, coating sags, streaks, the gaps between the parts are minimal. Be sure to check the strength and reliability of fasteners.
Availability of additional devices
Including dust collectors or adapters for connecting a vacuum cleaner, soft start and engine speed control functions, overheating protection, etc.
All other criteria are selected by the buyer independently. We recommend choosing products from well-known manufacturers such as Lagler, Stanley, Bosch, Aeg, etc. They not only provide warranty and post-warranty service, but also have a wide network of dealer and service centers in Russia and the CIS countries.
Technology
Sanding is not that easy. This is a rather complex and time-consuming complex, including six main stages.
Coating preparation
New decking should be checked for defects such as loose knots, loose planks, protruding nails, chips, gaps that are too wide. Old parquet is checked for integrity, damage and strength of fixation. To eliminate the shortcomings, parquet glue and putty masses are most often used (special liquids or PVA glue mixed with fine sawdust). It is better not to use elastic grouts and sealants, as they do not gain sufficient strength and “clog” the abrasive nozzle.
In order not to damage the drum or disk of the machine, all steel elements must be “drowned” in the floor by at least 3 mm. Damaged planks must be replaced with new ones, and not glued - fixed with glue and hardware. Dust and debris are removed with a damp cloth or construction vacuum cleaner.
Primary grinding
Rough grinding.
First of all, a drum or belt type machine is used as the most productive and efficient. This stage is most often called sanding or rough grinding of the surface, since an abrasive material with a grain size of 40 or 60 units is used. Bumps, scratches, old paintwork, dirt, etc. are removed.
Professional devices allow you to adjust the clamping force of the abrasive. This is very convenient, because it ensures a uniform fit of the nozzle to the surface, which means better work. A tape or a glued strip is installed on the base, carefully fixed and deep processing is carried out:
- When decking - along the fibers from wall to wall. Transverse movement with such laying is allowed only when the machine is turned at vertical enclosing structures;
- On the parquet "herringbone" - diagonally, with a uniform advance over the entire surface;
- When laying braid, shield or palace parquet (multidirectional installation) - crosswise without highlighting individual sections;
- On the artistic parquet - a circular movement, twisted in a spiral
The grinding process is quite dusty, so drafts are an undesirable phenomenon. Therefore, in the working room, be sure to close the windows and entrance doors.
The master must periodically check the condition of the abrasive nozzle and, if necessary, replace the worn part with a new one. This is a kind of preventive measure against strips and individual uncultivated areas.
At the end of the main work, it is necessary to process corners and other hard-to-reach places. For rough grinding of the floor with a grinder, an orbital machine or a “boot”, you will need circular nozzles of the same grain size - 40 or 60 units.
fine grinding
The final leveling stage is carried out by surface grinders with one or three disc machines. At the same time, all minor irregularities, dents, cracks and other defects on the floor boards are finally eliminated. For efficient work, circles of different grain sizes are used - 60, 80, 100 and 120. In some cases, even abrasive discs with a fineness modulus of 180 or 240 are used.
The work is carried out again along the fibers. Nozzles should be replaced with new ones as they wear out. Corners, steps and other difficult areas are processed with an angle grinder or "boot" with circles of the same grain size. At the end of the work, the surface must be vacuumed again or wiped with a damp soft cloth. Fine wood suspension and dust must be removed completely.
Filling gaps and smallest defects
After leveling the surface, you can start filling. For this, paste-like ready-made compositions for wood or special putty liquids are used. Professionals prefer the latter, since when mixed with sawdust from the processed plank floor, a mass of an identical shade is obtained, which perfectly fills all the voids, while being quite elastic and not cracking over time. The mixture is applied with a stainless spatula, which allows you to fill the pores, while cutting off the "raised" small wood fibers.
Finishing grinding
Before processing with varnish, oil or wax, it is necessary to polish the surface again. The work is carried out after the putty has dried and polymerized. It is implemented using a surface grinder and angle grinder with abrasive nozzles with a grain size of 120-160 units. The direction of movement is the same - along the fibers. After treatment, the floor must be thoroughly vacuumed again.
As a result, everything superfluous is completely removed from the surface and the floor becomes perfectly smooth.
Priming and topcoating
Even after applying the putty mass, it is advisable to prime the floor or treat it with impregnations with a fungicidal, bioprotective or tinting effect. If a ready-made colored putty was used, be prepared for the fact that the surface will be of different colors. Putty liquids mixed with fine wood dust from parquet do not have this drawback.
After the primer dries, the first coat of varnish, oil or wax is applied. Then an intermediate fine grinding of the floor or polishing (in oil or wax) is carried out using orbital or surface grinders with nozzles with a grain size of more than 140 units. Before applying the final layer of varnish or oil-wax mixture, the surface must be vacuumed again or wiped with a damp cloth.
Thus, it is necessary to spend a lot of time and effort on polishing a wooden floor, not to mention finances. But it is this technology that allows you to get a beautiful and remarkably even floor without the slightest flaw in a few days.
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When the part is ready, its surface should be carefully sanded.
On solid wood pieces, it is customary to smooth out saw cuts or remove traces of glue, sand where chips have broken off, or smooth out protruding wood fibers with the finest sandpaper before the wood is covered with stain or varnish. Even facings made of plywood or veneer, which have an almost smooth, flawless surface, can only be varnished without pre-sanding as a last resort.
Solid wood panels and parts may have almost imperceptible irregularities, which will become clearly visible after applying varnish, stain or other protective agent.
It is clear that grinding should not lead to the appearance of new scratches and grooves. You will avoid this danger if you use the appropriate sandpaper and stone for your product.
Cycling
When planing blanks from solid wood, more or less noticeable furrows remain after the planer. It is best to eliminate them in cycles.
Many home craftsmen prefer to process surfaces with only one cycle and completely abandon sandpaper. A well-sharpened scraper can clean planed surfaces and give them an almost flawless look.
The cycle is a metal rectangle with a cutting edge sharpened at a right angle, which is carried out along the surface. The cutting edge is blunt, so it needs to be sharpened from time to time. First, a chamfer (the beveled side of the cutting part) is ground on a whetstone or wheel, then the cycle is turned over, placed flat on the bar and in this position they drive over the stone in straight or circular motions, grabbing the cutting edge of the edge.
When working, the cycle is taken with two hands so that the thumbs are in the middle of the face facing you. Always place the cycle at an angle and guide in the direction of the wood fibers. Only use the scraper on solid wood, plywood or veneer. Chipboards quickly dull the cycles and leave notches on them. It is better to use sandpaper for processing putty surfaces.
The cycles clean out the bumps left by the planer, or the sticking out fibers of the wood.
Moisturizing the wood and applying a primer
Whether you will be sanding scrapers or otherwise, in any case, before sanding the surface of solid wood or plywood or veneer parts, it must be moistened.
To do this, it is better to use warm water (you can even hot if the part is made of solid wood). Then you need to wait until the parts are completely dry. Small dents under the influence of water will disappear.
But the incised wood fibers, pressed to the surface of the part before wetting, swell and, having dried out a little, stand upright. Therefore, the surface, which seemed flawlessly smooth before wetting, often becomes rough, fleecy.
After grinding, the surface becomes smooth again.
Primer for fast sanding
The surface of a wooden part, regardless of whether it retains its natural look or is covered with stain or varnish, is primed.
The primer closes all the pores, as if sealing them.
As a result, the hygroscopicity of wood is reduced, and the paint lays down better and more evenly than on an unprimed surface.
Make sure the room you work in is dry, dust-free and not too cool. So you create ideal conditions for work. It is more convenient to apply the primer with a soft flat brush.
The primer dries in about half an hour. But wait at least an hour before you start sanding the primed surface with the finest sandpaper (No. 240). Work only in the direction of the grain of the wood, change the sanding more often and beat out the fine dust that forms during sanding.
The surface, which seemed impeccably smooth, after moistening became rough, fleecy.
On the prepared surface, carefully apply the diluted primer with a flat brush.
Sanding flat surfaces
When sanding smooth surfaces, it is important to use sandpaper correctly: too rough sandpaper will scratch the wood, sandpaper without a boss treats the surface unevenly. The boss provides an even fit of the skin to the tree over a relatively large area. Usually use a cork boss. But a small wooden block with even, smooth edges is also quite suitable. You can also use special holder pads made of hard rubber or plastic: they consist of two parts - upper and lower, between which sandpaper is laid.
First coarse, then fine
To clean rough cuts with a saw, a sandpaper with a coarse-grained abrasive coating (grit 100) is used. Planed surfaces are sanded with 120 grit sandpaper. For fine, final sanding, use 180 or 240 grit sandpaper. Sand the wood all the time in the direction of grain growth and without undue effort. Experienced craftsmen avoid sanding surfaces for a long time, while their movements are very light, almost without pressure. As a result, the tiny ends of the fibers are only pressed against the surface, but not cut off.
A special grinding device - the so-called "sand plates" of different sizes and grain sizes. Each is a steel plate with tiny "skittles" protruding on the surface with sharp edges. When grinding with such a plate, due to the large distance between the "pins", a lot of sawdust is formed, and their cutting edges remain sharp for a long time. In the case of "sand plates" is noticeably "aggressive" than ordinary sandpaper.
If the surfaces of large parts are polished by passing over them with a boss wrapped in sandpaper, then when processing small parts, they act differently: a piece of skin of a suitable size is fixed on a workbench with strips of adhesive tape and drawn over the skin with a part. This avoids rounded edges. Before proceeding with further processing of the part, after grinding it should be thoroughly cleaned of dust.
When sanding even surfaces, use a special boss so that the skin is evenly pressed against the wood.
Small parts are best sanded by running along the sandpaper attached to the workbench.
Auxiliary devices made of cork and plastic for fixing sandpaper. "Sand plates" are glued to the overlay-handle.
Curved lines and profiles
Sanding complex edges and profiles requires a special flair and the right sanding tool. A boss with an overlay of sandpaper will not work here. It is often more convenient to work simply by taking the paper in your hand and holding its edges between your fingers so that they do not scratch the part.
When processing parts of complex shapes, it is advisable to use home-made "files". They are made in the following way. Narrow strips of sandpaper are glued onto planks or round sticks. With these "files" you can cleanly process the smallest roundings or the narrowest recesses on turned parts.
For sanding rounded surfaces, emery sponges are well suited, which are sold along with sandpaper in hardware stores. Sponges have on both sides an abrasive coating of coarse, medium or fine grit, and a thin soft pad between the coatings gives the sponge a special flexibility and elasticity. There are also grinding sponges that are thicker and rather hard: they are designed for grinding even surfaces without defects.
Wood dust from the sponge is removed by crushing it. You can also wash the sponge, but before using it again, you must wait until it is completely dry.
Coarse, medium and fine grit abrasive pads are especially good for rounding and profiles.
The emery sponges are so flexible that they tightly fit any rounding and even multi-step profiles.
If you hold the sandpaper with your hand, make sure that the edges of the paper do not scratch the wood.
Emery "files" can be made from strips of suitable sandpaper glued to strips or round sticks.
roundings
The processing of a wooden part is usually completed by slightly rounding its edges, that is, the sharp edges of the transitions from one plane to another or from the front surface to the end surface are slightly grinded.
Be very careful and careful when doing this work, as you can get hurt on the sharp edges of the part. Do not allow sudden movements when turning over the part, which can lead to it hitting some hard object and, accordingly, to damage. After completing the rounding, the treated surface can be varnished. Note that on the rounded edge the varnish lays down with a uniform film and holds better, while on the sharp edge of the transition from one plane to another this film is very thin and often breaks.
Make rounds using sandpaper only with a boss, which is directed at a 45 degree angle to both surfaces. The boss provides uniform grinding and rounding.
Make sure that the work, if possible, is carried out in the direction of the wood fibers, and on the end sides - from the middle to the edges. When sanding along the edge, you need to press the boss with sandpaper a little against the surface so as not to break off the wood fibers.
When rounding edges, drive the boss wrapped with sandpaper at an angle to the side edges or with light pressure along the edge.
On the farm, you often have to grind something, clean off the old paintwork. Most of all work with wood. Few manufacturers sell perfect products. Except a carpenter. And if there are perfectly processed boards, then their price is such that you involuntarily want to grind them yourself. Even taking into account the fact that the work is boring and uninteresting. Therefore, a wood grinder is one of the tools that should be in the home arsenal.
Types, purpose, features of work
There are different types of grinders that do the same type of work but with different results. There is a tool for rough (preliminary), medium (intermediate) and fine (finish) grinding. Part of the tool can even perform.
To choose a wood sander, you first need to decide what type of work you need it for. For rough grinding - smoothing out irregularities, differences in height - one type is suitable, for finishing grinding - bringing to the ideal - another type. Moreover, both tasks can be solved using different types of equipment.
angle grinder
The well-known grinder can also be used for grinding wood. With the function of rough grinding, it copes well. Of all the possible tools, this one is the most productive. If you need to quickly level large wooden surfaces - grinding the floor, walls, log cabins - this is work for the angle grinder. Minus - the surface is very uneven, it takes a long time to level all the pits and humps. If it still “passes” on a log house, then for any carpentry work the result is unsatisfactory. If only it is possible to purchase another tool, it is not worth using an angle grinder for grinding wood.
For wood, red emery circles are used - this is a special abrasive
For grinders there are special nozzles for grinding wood. The best option is petal or plate-shaped circles with sandpaper of different grain sizes. When they are installed, the working plane is below the protective cover, it is safe to work, you can move in any direction. It is necessary to carefully handle places with protruding heads of nails and self-tapping screws. We lower the tool from above, carefully move it. A sharp movement easily breaks the grinding wheel, so be careful.
By changing the grain size of the grinding wheels used, it is possible to carry out coarse and medium (intermediate) grinding. The work will take less time than if any other wood sander is used. But it may take more time to bring to a flat surface, since, with a lack of experience, there will be more flaws.
When sanding wood, the sandpaper is clogged, the speed of work is reduced. In addition to slowing down, there is another sign - the smell of burnt wood. It is not necessary to immediately change the disk, you can restore its performance. To do this, grind the metal for several seconds. Everything stuck - resin, wood fibers, dust - burns out, the surface is cleaned, the processing speed increases again. This trick, by the way, can be used with other grinders.
If you often have to clean and change circles, a Velcro nozzle is installed on the grinder. Replacing the sandpaper is much easier and faster - peeled off / stuck - a matter of seconds. But working with a nozzle is more dangerous. Due to its height, the grinding area is above the level of the protective cover; it does not fulfill its functions. During the start, it happens that an unreliably fixed circle or even the nozzle itself flies off. They have a small weight, injuries are not serious, but it's still an injury. An angle grinder with a smooth start helps to reduce risks, but all the same, you need to work with gloves, protective clothing with tightly buttoned sleeves, boots that cover your legs, and goggles.
Belt sander
It is called so due to the fact that the sandpaper has the form of a tape, continuously moving with the help of rollers. Therefore, such a wood grinder is also called "endless".
A wood belt sander is designed for rough and intermediate surface leveling. By setting sandpaper with a finer grit, you can achieve a medium finish. This is enough for joinery that does not go under painting. To bring it to perfect condition, you need a different type of wood grinder. Moreover, to eliminate long longitudinal scratches, you will have to carry out stepped grinding, changing the grain size several times - the scratches remain deep.
A belt sander is good if you need to remove the old coating - paint varnish
What is the advantage of a wood belt sander? It has good performance. The tape on it is installed in such a way that it turns out to be sanded close to the wall with one side. What are its shortcomings? Due to the design, not all points can be "reached". For example, corners, shaped recesses, grooves and other small details. It is not always possible to “crawl” between two parts (when processing railings, for example). Another drawback is that most of the belt grinders have a solid mass, it is difficult to work with them on weight, sanding vertical surfaces. But on a horizontal plane - they are the most productive.
The next disadvantages are a high level of noise, not the biggest grinding spot. It is so noisy that it is extremely uncomfortable to work without headphones. Why a small spot of polishing, because in appearance it is quite large? Even with a large belt width, it only sands in the center - the front and back part is not used due to the fact that it is raised to feed the rollers.
There is a belt sander for wood features in the work. To reduce the depth of the furrows that it leaves, it must be driven along the fibers. Then finishing polishing takes less time. And one more thing - if you gape in the process of work and leave the machine in one place for a long time, a solid “pit” is formed. Despite this, it is the most productive wood sander that is often used.
Orbital (eccentric)
The orbital sander for wood has a round sole with Velcro, on which sandpaper discs are attached. The discs are the same as for the grinder, so they are interchangeable. There are holes in the sole of the machine to remove dust. Dust is collected in a bag, a cassette-type container, almost all models allow you to connect a construction vacuum cleaner.
The work of an eccentric wood sander is based on the simultaneous rotation and movement back and forth (reciprocating movements). This achieves a fairly good speed for intermediate and finishing wood processing. When working with a grinder of this type, the platform moves in a spiral or orbit. Therefore, this tool is also called orbital sanders.
Eccentric sanders are good for processing curved or profiled surfaces - the machine is small in weight, it makes little noise, it is easy to control, the angle of the disk can reach recesses, cutouts, etc. With all this, it also handles large planes at a good pace. When using coarse grit sandpaper, it can be used for both coarse and intermediate sanding. The speed is less than that of the tape, but also quite acceptable. There are such machines with different radius of movement (eccentricity) - from 3 to 8 mm. By selecting this parameter, the main purpose is determined (more on this below).
The disadvantages of this type of machine are the impossibility of processing in the corners. The round platform is simply not included. Also - there is an area of uncertain grinding along the edges - it will not be possible to grind close to a wall or a vertical surface.
Vibrating
The sole of a vibratory grinder can be rectangular or triangular. During operation, it makes circular movements with a small amplitude - it vibrates, which gave the name to this type of equipment. This wood grinder is used for fine finishing - for varnishing or painting, but it has low productivity.
A vibratory wood sander with a rectangular surface allows you to process large areas, but with its help it is not possible to grind wood near vertical planes and walls - it starts to beat against an obstacle. Triangular in this regard is more suitable for working in corners and hard-to-reach places, but you still can’t bring it tightly to the wall.
Another disadvantage of vibrators is the so-called "lambs". If a grain of sand or other solid fragment gets under the surface, it leaves small circles on the wood - “lambs”. It is difficult to remove these traces. You have to use sandpaper of progressively smaller grit, gradually removing scratches. But if in the process something gets under the sole again, the process repeats again. Therefore, before work, the surface is thoroughly cleaned and a plyos is usually connected - for quick and timely removal of foreign fragments.
Oscillation
Strictly speaking, this is not a grinder, but you can grind with it. Moreover, those places that are not available for other types of machines are corners (even sharp ones), places directly at vertical walls. For grinding, a triangular platform of a special shape is installed on the tool, on which sandpaper on a self-adhesive basis is fixed.
During operation, the platform moves in a horizontal plane with a very small amplitude - the vertices of the triangle deviate by about 1.7 ° (this is an average of 2.5 mm). Due to this small movement, polishing occurs. Such a machine can be sanded in corners and close to vertical surfaces. Moreover, you can remove not only wood, but also smeared and dried glue. In general, an oscillation machine is used for finishing grinding in hard-to-reach places - due to low productivity and a grinding spot, it is unrealistic to process more or less large surfaces with it.
What type of grinder to choose
Summing up, we can say that for housework and construction, ideally, two grinders are needed - for rough and fine finishing. The most commonly used pair is tape + eccentric. If you are planning to start making furniture, then you cannot do without an oscillatory one.
If you do not like the result of the belt sander, you can purchase two orbital sanders with different eccentricities. For rough grinding, a tool with an eccentricity of 6-8 mm is suitable, for finishing grinding and even polishing - 2-4 mm. The only downside to this solution is that good eccentric sanders are expensive.
If the budget is limited, and the farm has a grinder (angle grinder), rough grinding can be done with it, and for intermediate or finishing, use orbital or vibration. Just keep in mind that vibration is the least productive, albeit the cheapest. If possible, buy an orbital one - it is more versatile and gives better results.
Technical Selection Criteria
Any tool is divided into classes that differ in working resource (and price). So a wood grinder can be household or professional. Household are designed for short continuous work with interruptions. Basically, it is recommended to work no more than 3 hours a day, periodically taking breaks of 15 minutes.
Professional models are designed to work for 8-12 hours, breaks are rarely needed or not needed at all. The working resource of such a tool is many times greater. For this, durable and reliable (read - expensive) materials are used. In addition, the productivity of such equipment is much higher, as a rule, there are a greater number of adjustments.
When choosing, the first thing to decide is what class your car should be. I must say that some manufacturers have a good household class, and some also have semi-professional lines. This is an intermediate class, as a rule, for private use it is optimal in terms of price / quality combination. Some models are used even by professionals.
General selection options
Although wood grinders differ, there are some common points that you need to pay attention to when choosing. Here they are:
These are the general points that you need to pay attention to. Now about what is important for different types of grinders.
Tape
When choosing a belt sander, you need to look at the following parameters:
You also need to pay attention to how convenient it is to change the tape. There are also models that allow you to quickly change the brushes. Sometimes spare brushes are even included.
Popular models of belt grinders
| Manufacturer | Model | Power | Tape dimensions (width/length) | Belt speed | The weight | Price |
|---|---|---|---|---|---|---|
| Interskol | LShM-76/900 | 900 W | 76 mm / 533 mm | 250 m/min | 3.2 kg | 55-90 $ |
| Makita | 9911 | 650 W | 76 mm / 457 mm | 270 m/min | 2.6 kg | 100-150$ |
| Bosch | PBS 75AE | 750 W | 75 mm / 533 mm | 350 m/min | 3.5 kg | 120-160$ |
| Interskol | LShM-100/1200E | 1200 W | 100 mm / 610 mm | 400 m/min | 5.6 kg | 100-150$ |
| Makita | 9404 | 1010 W | 100 mm / 610 mm | 440 m/min | 4.7 kg | 200-270$ |
Eccentric (orbital)
In addition to all the general parameters described, there are some nuances in choosing an eccentric wood sanding machine:
The selected model still needs to be tested in the store. To do this, install a disc of sandpaper on the platform and turn on the tool. Vibration should not be felt at all. This means that it is well balanced and will work comfortably.
Popular Random Orbital Sanders
| Manufacturer | Model | Power | Disc speed | Platform Oscillation Frequency | Disk size | Platform travel (eccentricity) | Price |
|---|---|---|---|---|---|---|---|
| Makita | BO5031 | 300 W | 12000 rpm | 24000 counts/min | 125 mm | 2.8mm | 90-120 $ |
| Makita | BO5041 | 300 W | 12000 rpm | 24000 counts/min | 125 mm | 3 mm | 100-200$ |
| Metabo | SXE450 TurboTec | 350 W | 13100 rpm | 8500 rpm | 150 mm | 6.2mm | 185-220$ |
| Bosch | GEX 150 AC | 340 W | 12000 rpm | 24000 counts/min | 150 mm | 4 mm | 175-220$ |
| Bosch | GEX 125-1AE Box | 250 W | 12000 rpm | 24000 counts/min | 125 mm | 2.5mm | 70-90$ |
Vibrating
First of all, you need to choose the shape of the sole. It can be rectangular (most often), square or ironing. The system for attaching sandpaper here is clamping, just a piece of sandpaper of the right size is pulled and fixed with clamps. For normal operation of dust removal in stretched paper, holes must be made in the right places (holes in the platform). It is best to connect a vacuum cleaner to remove dust, since the presence of dust under the platform leads to a large number of scratches. That is, instead of grinding, we get a damaged part. This is an important point.
What to look for:
The vibration grinder is used only for finishing grinding and is characterized by low productivity. Only paper with fine grain can be placed on it. Rough processing should be carried out with another tool.
Popular models of vibratory grinders
| Manufacturer | Model | Power | Platform Oscillation Frequency | Tape (sole) dimensions | Platform stroke | Price |
|---|---|---|---|---|---|---|
| Interskol | PShM-115/300E | 300 W | 10500 counts/min | 230x115mm | 35-50$ | |
| Makita | BO3711 | 190 W | 22000 counts/min | 228x93 mm | 2 mm | 60-75$ |
| Makita | BO3700 | 180 W | 20000 counts/min | 230x93 mm | 2 mm | 50-60$ |
| Bosch | PSS 200 AC | 200 W | 24000 counts/min | 230x93 mm | 2 mm | 50-70$ |
| Hitachi | SV12V | 300 W | 20000 counts/min | 228x114mm | 2.4 mm | 100-130$ |
