Sandpaper: types of grit and how to sand correctly? How to sand wood with sandpaper. Different ways of sanding wood Do-it-yourself wood sanding

When the part is ready, its surface should be carefully sanded.

On solid wood parts, 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 proceed 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.

How to properly prepare wood for applying varnish to make it smooth?

Fine wood finishing is the stage that crowns the wood processing process and ensures its true beauty. If you learn the basic steps of sanding and finishing and the techniques involved, you will be able to always guarantee a perfect result. This article contains the most helpful tips.

wood sanding

Wood can be sanded with both sandpaper and a grinder. Scratches are less noticeable when they run parallel to the grain of the wood. However, even the smallest scratches across the fibers will become visible after applying varnish (or paint). Wood sanding is done very carefully.

Grind curved surfaces and other elements where the grinder is inconvenient to use, should be done manually. It is important to use paper of the same grain size and try to apply the same force in all areas.

Any centrifugal grinder leaves practically no scratches, so it is advisable to use such a tool in places where the direction of grinding changes and where it intersects with fibers. In this case, the machine should work slowly (no more than 2-3 cm per second) and with little pressure, otherwise you risk causing spiral scratches (in the next photo).

Such scratches are left by a centrifugal grinder when used incorrectly.

Sanding wood should begin with coarse sandpaper, gradually moving to finer and finer grit types. Whether sanding by hand or with a machine, use 80 grit/inch paper first, then 120 grit and 180 grit.

Lacquer selection

Do not rely on samples displayed in stores. The actual color is highly dependent on the type of wood being treated and how it has been prepared for finishing. Therefore, collect wood scraps, sand them and use them to test the varnish.

If this is not possible, then apply a test portion of the varnish on an inconspicuous area (for example, on the bottom of the countertop). Leaving the varnish on the surface for more or less time, you can get different shades.

To obtain special colors, varnishes from the same manufacturer can be mixed.

Water-based polyurethane varnish has little effect on the natural color of the wood. At the same time, oil-based products have a rich tone that can drastically change the color of the tree.

You will need a fairly bright light, while directing it should be at a fairly sharp angle to the surface. Inspect the wood for flaws and carefully mark them with masking tape. Then sand them down.

Some types of wood absorb the varnish unevenly, which leads to the formation of dark spots on the surface. Birch, maple, pine and cherry can play such a cruel joke with you. This effect is quite difficult to avoid, but it can be limited by treating the wood with a conditioner before applying varnish. The conditioner prevents the wood from absorbing uneven amounts of varnish into the fibers. Such products are sold along with paints and varnishes.

In these photos you can see how to choose a varnish. The choice of varnish should be made in accordance with the type of wood.

The brush is the best tool for applying polyurethane varnish. For water-based varnish, a tool with synthetic nylon or polyester bristles is the best choice. For oil-based formulations, natural brushes should be used. In both cases, do not skimp on spending when buying these devices. Quality brushes pick up more polish, apply it more smoothly, and are much less likely to lose bristles on the finish coat.

If you wash the brush immediately after work, it will serve you for a long time. Processing wood varnish with a brush provides efficiency and excellent results.

If after applying the next layer you suddenly notice a flaw in the coating, an uncovered spot or something like that, you will immediately rush to cover it up. You shouldn't do that! While the polish may still look wet, there's a good chance it's already set and you'll only mess it up with a touch of the brush. There are exceptions to this rule: you can pierce small air bubbles with a needle, you can pull a hair out of a layer, or you can pull out an unfortunate fly with tweezers.

Where it is difficult to apply the varnish with a brush, rub it into the wood with a soft, non-stringy cloth. When rubbing, the varnish layer is much thinner than when spreading with a brush, so it is worth repeating the procedure several times. Rubbing is only suitable for oil-based formulations, as water-based varnishes dry too quickly.

On large surfaces, water-based polyurethane compounds are conveniently applied with a paint roller. Due to the fact that water-based varnishes dry quickly, applying them with a brush over a large area can be difficult. Before you start varnishing wood, clean the workpiece and work area. Dust when applied to a fresh coat of varnish will ruin your work. So clean up your desk and let the dust settle.

Always lightly sand the surface between coats of varnish - this will help to achieve evenness and perfect laying of the layers. Wait for the previous coats to dry before reapplying wood varnish.

• Andrew
• print

Source: https://prorab.guru/sovet/otdelka-drevesiny.html

How to grind a log house

When talking about log sanding, they mean the material from which the building is made, however, there are some differences between log sanding and different types of timber - these should be considered later. But before deciding how best to grind a log house, it is necessary to decide at what point after its construction it is necessary to start grinding the walls.

When to grind a log house

It is better to grind dry wood - it turns out better, while working with wet wood leads to the separation of fibers and presents a certain difficulty. But this will have to wait quite a long time. Some breeds can dry up to 7 years. However, after this long period, the log house may lose its attractive appearance - a tree without protective coatings will be subject to any negative influence from the outside, it may dry out, crack, rot due to moisture.

Of course, it would be possible to cover it with paint or other protective agent, but without grinding, the applied coating will not have a strong adhesion to the natural material, which means that all the listed misfortunes will still happen, only a little later.

So it turns out that sanding should be done on naturally wet, not yet dried wood, in order to cut off all the bumps and prepare the material for processing with tools that prevent premature wear.

Before sanding a log house, let's ask ourselves what other benefits sanding provides.

• Sanding removes the pores of fungi and mold from the surface of the wood.
• With the help of this type of work, dirt and roughness are removed from the walls.
• In this way, you can protect the walls from direct sunlight, which causes the wood to darken.
• As a result of the procedure, the impregnating agents fall on the tree evenly.

Now is the time to think about how to grind the log house.

Sanding tools

To process logs, you need a tool that is convenient for rounded surfaces, so that you can opt for a grinder - an angle grinder.

For work, you will need special disk nozzles with an emery coating.

In the case of working with a bar, a belt sander is suitable. If you decide to do this yourself, use a more compact and lightweight version of the tool.

In addition, you will need a large amount of sandpaper, since not all areas can be reached with a tool.

And so, we came to the most important thing - how to grind a log house.

Grinding rules

• For safety reasons, prepare goggles and a mask with a respirator, to avoid getting small particles of wood into the eyes and respiratory tract, use work gloves.
• Distribute the work so that a well-treated tree is immediately covered with a protective agent.
• First, coarse emery is used, and only at the end, emery with a finer grain.
• Get ready for the fact that the process of work is quite lengthy.

Wood floor maintenance - sanding

Sanding is a finishing job and is an essential part of caring for wood floors. How to sand a wooden floor is a pressing problem for many owners of this flooring.

In order for wood floors to serve for a long time and please with their appearance, they must be constantly kept in perfect condition: painted, covered with tinting compounds, wax or varnish, but all this will not have a result if the wood has not been sanded first. It is worth immediately finding out what is the best way to sand a tree.

The work will require some costs - no, you do not have to buy special equipment, you can rent a grinder, or you will have to invite a specialist.

But for full-fledged work, you need to acquire a tool for places that the grinding device simply cannot reach.

• This is sandpaper of different grain sizes in large quantities.
• A tool for simple (rough) grinding - scraper.
• You will also need the so-called "boot" - a mini-machine for difficult areas.

Now we find out how to properly sand a wooden floor.

Floor work

1. We start by taking out all the furniture, removing the baseboards.
2. We check the floors for the presence of protruding nails and reliable fastening of the floorboards.
3. We fill the equipment with coarse sandpaper (40) and go through the room diagonally.
4. We adjust the pressure of the drum by half - it should be medium.
5. It should be remembered that you need to turn the car on and off while driving.
6. After the first pass over the area, the emery is replaced with a smaller one (100-120).
7. At the end, we process corners and hard-to-reach areas with the help of a “boot”, cycles and emery.

How to sand a wooden or parquet floor, you now know.

After the procedure, the floor must be vacuumed and you can start painting or applying varnish.

Source: http://wood-prom.ru/clauses/sdelay-sam/chem-shlifovat-srub

Sanding wood with a grinder and manually, choosing the grit of sandpaper

Wooden products almost always require leveling and sanding at some stage. In the course of such work, all traces of glue, protruding pile, bumps, chips and other defects must be removed from the tree. Usually, the wood is sanded before applying an adhesive, protective or decorative material (primer, paint, varnish, etc.) to it.

The grinding process has many subtleties and pitfalls, which does not hurt to know in advance, doing work at home.

What and how to grind

The goal of wood sanding is to make it as quick and easy as possible. effectively remove defects without leaving noticeable deep scratches. To do this, you can use special tools - now their price is not too high.

In free sale you can find several varieties of grinders:

• tape;
• oscillatory;
• grinders (UShM);
• surface grinding;
• orbital.

On the grinder, you can install not only abrasive wheels, but also brushes. So, nylon brushes are actively used for grinding wood. They allow you to make the surface not only smooth, but also highlight the texture of the tree, choosing softer fibers. This process is called brushing.

For large surfaces made of wood and materials based on it (veneer, chipboard, fiberboard, plywood), belt and surface grinders are best suited.

In addition, many still prefer to grind by hand for decorative items, furniture, toys, frames, and this is not such a bad way - it allows you to achieve a perfectly smooth surface efficiently and without unnecessary expenses. At least, when working with your own hands, you won’t need to think about where to get a grinder (ask a neighbor, buy it in a store, rent it, leaving a deposit).

Belt type machine

Tape machines are so named because the sandpaper here is made in the form of a tape and it is constantly moving thanks to the rollers. This machine is designed for intermediate and rough sanding. But in order to achieve perfect smoothness and a perfect finish (this is especially true for those involved in the manufacture of furniture), you will have to additionally use other grinding equipment.

The belt sander can be equipped with different types of sandpaper. And, for example, when inserting fine-grained sandpaper, it is quite possible to achieve a result that is normal for carpentry that goes for painting. And, say, to eliminate long scratches, you will have to carry out stepped grinding, changing the grain several times.

The belt sander has excellent performance. But at the same time, it should be recognized that the tape on it is in such a way that not all points and recesses of the surface of the board can be properly processed.

Even with a significant width of the belt, it grinds mainly with its center. The parts of the tape behind and in front are not used for this. They are in a slightly raised position, and their main function is to feed to the driving roller mechanisms.

Another obvious drawback of tape equipment is a solid mass; it is quite difficult to perform any actions with such machines on weight, processing vertical products.

There are tape machines for grinding wood and such a minus as high noise - it will not be very comfortable to work without earplugs or headphones. And one more important point: if you leave the machine in one place for a long time during work, a fairly noticeable hole will appear.

Surface grinder

Even sanding large woodwork with a surface grinder is pretty fast. The key organ of the apparatus is a flat, rather large plate (sole), to which the desired abrasive is attached. This design is famous for the almost complete absence of dead zones (that is, zones that cannot be reached with a machine and processed tolerably) - any corners are relatively easy to grind.

The demand for flat grinders among wood craftsmen is determined by their moderate price and availability of equipment. When choosing such a machine, you should pay attention to such parameters as motor power (usually we are talking about indicators in the range from 150 to 300 watts), weight, amplitude and frequency of the sole.

Manually

Sanding wood by hand, of course, requires a lot of labor and physical effort. But this method of grinding is a priori less aggressive and allows you to fully control the process. Even in hard-to-reach places - in corners and on complex curvilinear bends - you can get decent quality grinding when choosing a manual method.

With the so-called interlayer grinding of finishing coatings, manual work has no alternatives at all - only it eliminates the risk of damage to the already applied finish. Manual processing (when compared with grinders) allows you to get the most even and smooth surface, although it takes many times more time.

pads and sponges

A block is an extremely useful device for manual grinding, its presence and proper use can speed up the process. The block, as a rule, is an ordinary wooden block wrapped with sandpaper. Its abrasive side should be on the outside, and the non-abrasive side should be attached to the bar with a large stapler or PVA glue. Some hardware stores sell ready-made pads with sandpaper, that is, you can not do it yourself, but simply buy it.

For sanding wood, polyurethane foam sponges are also used. They are more convenient to use than emery, as you can rinse them under water after work. Abrasive sponges and cloths are great for fine manual sanding of wood, allowing you to process the smallest details. They can also be used for sanding primed or varnished wood.

Sandpaper selection

What is the best way to sand wood? Which sandpaper to choose for your work? In fact, these are not such simple questions. Sandpaper today is made from different materials:

• pomegranate (very rare);
• silicon carbide;
• ceramics;
• electrocorundum and others.

Garnet is characterized by the fact that it grinds faster than all other materials, but gently grinds the tree. And silicon carbide, according to experts, is great for sanding the lacquer and removing debris and dust stuck in it.

Ceramic sandpaper is usually used when sanding wood with grinders. Skins with a ceramic working surface are among the hardest and most expensive abrasives. The same can be said about corundum.

But the most important classification of sandpaper is the classification by grain size. At the moment, coarse-grained, medium-grained and fine-grained sandpapers are distinguished.

In the Russian Federation, the marking of emery products complies with the ISO-6344 standard - grit is indicated by the letter “P” and a number. The larger this number (it shows the exact number of sieve wires in one inch), the smaller the grain size. And, accordingly, the product becomes even smoother after grinding with such sandpaper. Usually this marking is indicated on the packaging.

It is advisable to buy several types of papers for polishing wood at once. Coarse-grained paper is considered to be paper, which is marked with a number from 40 to 80, it is suitable for rough processing. In the marking of medium-grained sandpaper there are numbers from 100 to 150, and in the marking of fine-grained sandpaper there are numbers in the range from 180 to 220.

Note! You can find marking according to GOST with the letter M. It means fine-grained sandpaper.

In addition, sandpapers come with closed or open filling. The former are very densely covered with grain - that is, their abrasive is more effective and efficient. And on the basis of sandpaper with an open filling, there are much fewer grains (usually their share is no more than 60% of the entire surface of the canvas), so it is not so effective. But on the other hand, the presence of empty space between the grains does not allow the sandpaper to clog quickly - this prolongs its service life.

In this way, sandpaper with a closed coating is suitable for hard surfaces, and with an open one - for more pliable and soft.

Dry and wet grinding

For sanding wood before applying finishing coatings and after them, two relevant techniques are used - dry and wet.

Dry sanding increases the effectiveness of the abrasive and makes it possible to use it more accurately. At the stages of intermediate grinding of delicate finishing materials, this is what you need. The disadvantage of this technique is that the skin is quickly clogged with debris. To eliminate this problem, experts advise using an emery cloth with anti-clogging properties.

Wet sanding involves applying a liquid to the grainy surface of the sandpaper. The role of such a working fluid can be an ordinary soap solution, white spirit and mineral oil.

Abrasive during wet grinding becomes clogged much more slowly and, accordingly, its service life increases. But the wet method also involves the formation of an unpleasant mess of chips and foam. In this case, the home craftsman will have to periodically wipe the wooden product.

Manual grinding rules

Do-it-yourself sanding should be started with the coarsest sandpaper available in order to eliminate obvious defects from the surface of the wood. But here it is still necessary to take into account the nature of the damage that needs to be eliminated.

Note! If the defects on the surface are minimal, then there is no point in starting with the P40 abrasive (this abrasive is only suitable for very large bumps and depressions).

You need to act on the surface correctly: it is best to move the block or just sandpaper in a straight line along the fibers in the back and forth direction. And grinding, for example, in a circular motion, can lead to extra scratches.

Having reached the edge of the surface to be treated, be sure to grind off sharp corners. Soon, as a result of exposure to coarse-grained abrasive, dust hills will begin to appear on the tree. They should be carefully removed with a vacuum cleaner. Then you can proceed to processing with the next sandpaper, which has a medium grit.

This processing is carried out according to the same principles as described above. The final stage is grinding with an abrasive with the finest grain. After that, the wooden product should become completely even, no flaws should remain on it.

Source: https://DrevoGid.com/zashhita/shlifovka

Hand grinding

Manual grinding is the processing of parts and surfaces with the help of hands and an abrasive tool, in which the top layer of the material being processed is removed.

The value of hand sanding

Currently, the industry offers a large number of electrical machines and tools designed for the grinding process. However, in many cases, it is manual grinding that has the advantage, which can provide:

• good uniform processing;
• better control over the process;
• high quality of work in hard-to-reach and difficult places.

Sanding with a grinder, grinder, drill or other power tool gives a high-quality result when working on flat surfaces. However, the processing of corners, edges, curved places is a difficult task for machines. In such cases, it is better to work by hand. Manually, you can easily control the movement and degree of pressure of the abrasive tool. As a result, the surface becomes perfectly smooth and even.

Mostly manual grinding is used when working with wood. To get a beautiful product, it is necessary to perform grinding before applying varnishes and paints. This treatment opens the pores of the wood and removes small irregularities.

Also, manual sanding is performed to maximize the adhesion of paints and varnishes on surfaces to be painted, especially if a second layer is applied on top of an existing layer. Grinding removes surface contaminants, in addition, the surface acquires a slight roughness, which allows the paint to penetrate deeper into the structure of the material and create a durable coating.

When working with primed surfaces, the best adhesion of the topcoat is obtained by fine sanding by hand with the finest sanding media.

Choice of abrasive paper

Manual grinding is carried out with a sandpaper, which is a special abrasive tool. It is a prepared base made of fabric, paper or metal, on which an abrasive material is applied with glue. Grinding skin is available in the following types:

• sheets;
• tapes;
• disks;
• circles, etc.

The most famous and simple tool for manual grinding is sandpaper. It consists of a fabric or paper base with a layer of abrasive grains of artificial corundum or silicon carbide glued to it. It is the layer of these particles with sharp edges that removes the layer of material from the treated surface. Currently, there are such main types of sanding paper:

• glass coated emery;
• skin with grains of corundum;
• silicon sandpaper.

These types are not particularly different from each other, they all have one drawback - a short operating time. The fact is that as a result of use, the abrasive grains wear out, the base wears out, and the gaps between the grains become clogged with particles of the removed material and dust. But at the same time, the grinding skin has a low price, so you can purchase this consumable as needed.

You should choose a sanding paper according to the grain size, which is indicated in numbers. The grit class corresponds to the scope of this abrasive:

• from 40 to 80 - designed for preliminary grinding and removal of the old coating;
• from 100 to 140 - suitable for fine work and intermediate grinding when applying varnishes and paints;
• from 160 to 240 - for grinding thin layers of enamel coatings.

The higher the number indicated on the sandpaper, the finer the grit.

In addition, abrasive skins differ in the density of the abrasive filling, the method of applying abrasive grains, the properties of the base, the adhesive material and, accordingly, the price.

sanding block

The main device for hand sanding is a wooden block wrapped in emery cloth, which professionals call a sanding block. The design of such a bar is so simple that anyone can make it with their own hands. Most often, a sanding pad is made of wood, for which a parallelepiped is cut out about 200 by 30 mm in size with a thickness of about 10 mm.

Such parameters allow you to comfortably hold the bar in your hand for grinding surfaces of any configuration. A sandpaper is attached to a home-made workpiece with the help of small nails. For a quick change of sanding paper, it is more convenient to use a bar of a special design, in which there are clips to hold the emery.

You can buy such a sanding pad, and if you wish, you can make it yourself from any suitable material:

• tree;
• traffic jams;
• metal;
• plastics, etc.

In any workshop, you can find remnants of foam, tile, or other dense material that can easily be turned into a good helper for surface machining. You can also use old sponges or computer mouse pads that hold their shape when wet and can be used for wet sanding. a video on how to make a bar yourself can be seen on the relevant sites.

For work, it is better to choose pads of a small size, since they are more convenient to use, controlling the degree of stripping in the process. It is especially good to work with such a block when grinding a surface with a complex profile, as well as for processing hard-to-reach places (recesses, corners, joints, edges, etc.).

abrasive sponge

If it is necessary to sand carved decorative surfaces with complex relief, as well as spherical and rounded shapes, it is recommended to use abrasive sponges. Their choice is quite wide. Externally, the grinding sponge is similar to a regular dishwashing sponge. Abrasive sponges are distinguished by the material used - an abrasive coating is applied to a durable polymer base.

Sponges and pads are great for sanding MDF and wood, and can be used for both dry and wet sanding. Separate modifications of the sponges are intended for the final polishing of the product. Working with them, you can grind the smallest surface roughness, and then finish polishing to a shine with a sponge containing wax.

Abrasive sponges are more expensive than traditional sanding pads, but they will last long enough, while in some cases it is impossible to do without them (grinding inside corners, grooves and other difficult areas).

Features of grinding by hand

In the process of manual grinding, constant hand control over compliance with the work technology is carried out, so the surface always turns out to be perfectly smooth. However, to achieve the best result, some subtleties of the process should be observed:

• when grinding even flat surfaces, use grinding stones;
• sand only along the fibers (otherwise scratches may form);
• use large skins first;
• finish grinding with small skins;
• clean sanding paper from dust as needed;
• use a respirator while working.

When sanding dry, the sanding should be cleaned frequently. When sanding wet (with a humidifier such as white spirit or soapy water), you need to constantly wipe the work surface.

Source: http://www.zavodkorund.ru/stati/ruchnoe-shlifovanie

How to sand wood properly

On solid wood parts, 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.

how to sand wood

When the part is ready, its surface should be carefully sanded.

Checking wood for light

Irregularities on the surface of a wooden part are more noticeable if the light does not fall directly, but along the surface: then all the depressions, mounds and protruding fibers are clearly visible. Hold the part against a light source if you want to check the quality of your work.

Do not sand wood with coils of thin steel wire.

Hardware stores sell the finest steel wire rolled into coils. On the packaging of such a skein it is written that, in particular, they can grind wood. But if you intend to varnish the part, never use this product for sanding. Despite thorough dusting, tiny particles of wire can remain and after a while begin to rust, staining the surface and reducing the durability of the varnish.

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.

scraper tool for fine stripping of wood veneer

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 force. 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 "pins" 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 proceed 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.

wood sanding

When sanding even surfaces, use a special boss so that the skin is evenly pressed against the wood.

wood sanding

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.

sandpaper for wood

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 onto planks 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 the 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

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

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

All photos from the article

Perhaps for sophisticated people this will seem strange, but the request, how to sand a tree, is quite relevant. Therefore, it needs to be given due attention. We will provide you with all possible answers on the topic, as well as show a visual video in this article.

Different ways to sand wood

Classification of sandpaper and types of abrasive

Note. Basically, all sandpaper is classified by grit. That is, by the size of the grain of the abrasive.

Marking and grit table

Electrocorundum:

• a mixture of bauxite agglomerate, iron shavings and carbonaceous material is melted in arc furnaces, from which electrocorundum abrasive is obtained;
• it has a high density and excellent cutting ability, but in some cases these properties are improved by adding alloying additives to the dressing, for example, chromium oxide (the abrasive in this case has a ruby ​​​​color, as in the photo above);
• sandpaper with electrocorundum is produced most often.

Silicon carbide:

• to obtain an abrasive in Acheson furnaces, graphite is sintered with silica, resulting in shiny, irregularly shaped crystals with sharp edges;
• Silicon corundum is convenient in that during operation, the crystals break and form new cutting edges. This property allows for a long time to keep the work surface, avoiding clogging.

Pomegranate:

• for grinding wood, garnet is the highest quality abrasive, despite its softness (6.5-7.5 according to Mohs);
• The paper wears out quite quickly, but due to the same grain size, sanding gives a smoother surface than other abrasives.

Diamond, elbor:

• diamond has the highest hardness and is slightly inferior to it in this elbor, therefore, such abrasives can be called the best in the world;
• the problem is that the price of these minerals is too high, so they are rarely used for sandpaper.

Sanding methods

Note. For sanding wood, the instruction recommends two main methods for use - manual and mechanical. But each of them has several options, which we will now discuss.

The most common is the manual method of wood sanding, and this is not surprising despite the technological progress. The fact is that it is often necessary to process rather small, hard-to-reach or embossed surfaces, where it is impossible to get close to various electrical devices.

For embossed surfaces, of course, it is better not to use anything at all and keep the paper in your hand - the wood sandpaper will repeat all the curves that you will feel with your fingers. So the processing will be of the highest quality.

In extreme cases, a piece of foam rubber is placed between the fingers and paper - the sensitivity, of course, decreases. But, nevertheless, such a device is able to go around all the contours, for example, on a baguette or baseboard, evenly grinding the surface.

For flat surfaces, an ordinary bar is often used, wrapping it with sandpaper. So you get two flat planes - one machined and the other influencing, which leads to the greatest production efficiency.

And, of course, there is a special device for this, called a block. The sheet on it is simply stretched with clamps that are located along the upper edges of the board - this device is shown in the top photo.

If it is provided for over a large area, then in such cases it is possible to use an angle grinder (angle grinder) - a grinder or a milling cutter, on which a special round (disk) nozzle is put on, where there is Velcro on the working side.

Then, sandpaper of the desired grain size is applied to this disk. But such a device is effective for rough processing, for example, when grinding log or timber buildings.

A better surface treatment of wood can be done with a belt sander, but it is designed exclusively for flat surfaces. For example, if you need to sand the floor with your own hands, then there can be no question of manual work here due to the too large processing area.

But the machine will cope with this pretty quickly. Narrow paper (specially produced for this purpose) of the desired grain size is put on the broaching mechanism - grinding is of high quality.

Conclusion

We hope that you understand how to properly sand a tree and you just have to choose the right paper grain. But if you still have questions, then you can ask them to our specialists in the comments section - we are ready to answer all questions.