How to Dress a Disc on a Lawn Mower

The main spare part of the angle grinder (angle grinder) is a replaceable cutting tool. An abrasive disk rotating at high speed cuts, grinds or polishes materials. To process metal, circles are made of abrasive chips, steel mills are used for wood, and metal wheels with diamond dusting are used for stone. Special nozzles – brushes, petal emery wheels further expand the capabilities of your angle grinder. Next, we will find out what types of discs are, how to remove the old one and put in a new one, and also consider the possible problems that arise during the replacement process, and ways to solve them.

Types of discs for angle grinder: how to choose the right one

The industry makes an angle grinder and disks for them in standard sizes: 115, 125, 150, 180 and 230 mm. Angle grinder from 180 mm is used for cutting stone. The most common size of machines for home and garden is 125 mm, the most disks and nozzles are produced for them.

We propose to divide the disks according to their purpose: cutting, grinding, grinding and peeling. Consider in detail each view.

Cutting

Cut metal

Cutting materials is the most common task during repair and construction, a simple abrasive wheel for metal is easily cut by a steel bar, roofing iron or plastic. These circles are made of corundum (crystalline alumina) or electrocorundum (synthetic corundum).

Sawing stone

For cutting stone, we recommend taking a special disc – they use another abrasive – silicon carbide. He will cope with white silicate brick and slate. But the red brick, tile and especially concrete – they will not succumb to it – you need to take a diamond disk.

Dissolve the tree

Wood cutting discs are very similar to a circular saw blade. Actually, this is the circular disk, only the mounting diameter of 22.2 mm is suitable for the spindle angle grinder.

Diamond

As you know, diamond is a very solid mineral, so diamond discs can easily cope with red brick, porcelain stoneware, and tile. The main material that is cut with diamond blades is concrete.

Diamonds must be handled carefully – steel is not cut with a disc, it must not be overheated. After only two minutes of sawing concrete, the disc will become very hot – pause. Around the circumference of the disk for dry cutting slots are made for cooling.

They produce disks for wet cutting of ceramic tiles and porcelain. Water cools the disc and flushes out hazardous dust.

How to choose the thickness of the cutting discs

Every master knows that the finer the instrument, the better. Less material goes into the chips, easier to saw, the cut comes out cleaner.

Discs for 115 and 125 mm grinders are produced with a thickness of 1.0–2.5 mm. Discs 150 and 200 mm – 1.8–4.0 mm thick. The pressed corundum powder is reinforced with a synthetic mesh.

The recommended cutting disc thickness is 1.6 mm.

Grinding

The next most important work, which the craftsmen entrust the angle grinder, is grinding and polishing. A similar treatment is applied to metal, wood, plastic and other materials.

How to Dress a Disc on a Lawn Mower

Petal circle on a tree: dozens of emery petals cut chips quickly

The choice of grinding discs is very wide. If you are restoring a sideboard, a petal circle is suitable for removing shellac layers. It captures large surfaces and cuts a lot of material in one pass.

The grinding nozzle is a plastic wheel to which the sandpaper is attached with Velcro

Another nozzle is screwed onto the spindle by an angle grinder. Sandpaper sticks to it on Velcro. For rough machining – P60 or P80, for finer – P120 or P180. With a decrease in grain size, grinding smoothly passes into polishing.

Alpaca polishing disc

Especially for polishing, there are nozzles in the form of pillows, felt or fabric discs. Before work, they apply a polishing paste, for example, GOI.

Grinding wheels

In fact, there are special machines for sharpening tools – sharpeners. Nevertheless, the rotary disc angle grinder is able to correct a blunt ax or cleaver, knife or scythe. Taking into account the wishes of the masters, the industry produces grinding wheels for 115 and 125 mm grinders.

Sharpening discs turn the angle grinder into a sharpener

Disks are made of coarse abrasive, pressed into a thick plate (more than 5 mm) with a bulge in the center. If you install such a disk on the spindle, the flange is hidden in the recess and does not protrude above the plane of the disk. Rough grinding wheels are also used to clean welds.

Peeling brushes and discs

Masters who repair houses in the middle of the last century are faced with removing oil paint from the walls. Wire brushes are suitable for such work.

No paint can stand against such a steel cup

A brush is a cup, around the circumference of which there are steel or brass plaits. Differ in thickness and rigidity of a wire – for rough and thin peeling. The brush is screwed onto the spindle through an M14 thread.

A stone grinding disc evenly cuts old cement

After removing the oil paint, the curved concrete wall must be sanded. Only an angle grinder can handle this task. The working surface of the diamond peeling disc is perpendicular to the axis of rotation. Synthetic diamonds cut and smooth concrete like sandpaper wood.

How to replace

Disks for an angle grinder are consumables, they are quickly erased when cutting. The worn out disk needs to be replaced. Let’s see how to do this with the example of our Interskol-115 angle grinder.

Step-by-step instruction

The disk is mounted on the spindle by an angle grinder with a clamping flange with M14 thread. To unscrew the flange, an open-end wrench is included in the kit. Its pins cling to the holes of the flange.

The spanner will unscrew the flange

To unscrew the flange, the spindle must be locked. To do this, a latch is made on the side of the case opposite to the disk. When the button is pressed, the cotter pin enters the hole of the driven gear disk and prevents the spindle from rotating.

Button locks the spindle

Insert the open-end wrench into the holes of the flange. With our right hand we press the lock button, at the same time we turn the key counterclockwise with our left and we remove the flange from its place.

The spanner is inserted into the holes in the flange.

If the flange succumbed, unscrew it by hand, remove and set it aside.

Upper flange removed

Remove the old disk. We don’t need it anymore, it can be thrown away.

Old disc removed

Remove the bottom flange.

Bottom flange removed

With intensive sawing, rip-off from burnt metal particles and abrasive is formed on the inside of the casing. Use a steel brush to clean the casing.

The brush cleans the casing

We install the lower flange on the spindle, making sure that the flats on the flange coincide with the grooves on the spindle. Put the gasket on top.

Lower flange and gasket supplied

We put the disk in place, close the second gasket.

New disk installed

Hand-tighten the upper flange against the direction of rotation of the circle (in our case, clockwise), holding the abrasive disk. With our right hand we hold down the lock button and twist by hand until we feel resistance. We insert the open-end wrench and twist a little more, no more than a quarter of a turn. It is not necessary to tighten the flange too much, the disc will warp.

Video: How to Dress a Disc on a Lawn Mower


Disc replaced, angle grinder ready for use

This completes the disc replacement, you can continue sawing. Sometimes when changing a disk, obstacles get in the way of the master. What to do in such situations – consider further.

Possible difficulties in the process

What to do if there is no key

The spanner for the angle grinder is not attached and may well be lost. How to unscrew the flange in this case?

  1. We make an open-end wrench from a nail. We take a “hundredth” nail, bend it in the shape of the letter “P” so that the distance between the uprights is equal to the distance between the holes in the flange. Cut the point and head with a hacksaw. We stick the resulting "key" into the holes of the flange and unscrew the mount, not forgetting to fix the spindle. If the nut is tightened tightly and there is not enough finger force, insert another nail between the vertical segments – the lever will be larger.
  2. We use the gas key. We take a large pipe wrench, it is also called the "gas". Such a tool plumbers twist steel pipes. We split the key so that it encircles the entire flange. We try to move the nut from its place, securing the spindle. The gas key has a huge shoulder. If you apply force, the spindle lock will break.
  3. Percussion nut. Take a metal bar or thin chisel. Lock the spindle. Knock on the edge of the hole in the flange in the direction of disk rotation. So you can remove the nut from its place. This method is not the safest: the tool damages the flange and breaks the key holes.

The disk is broken, the flange is jammed

Imagine that the master makes an anvil from a steel rail, cuts the point of an angle grinder. The disc warped in the material and jammed. The motor continues to work and tightly tightens the flange. All the work got up. How to change a disk if now it does not turn off?

  1. We disassemble the gearbox. Unscrew the mount and remove the gear housing. We hold the spindle shaft with a gas wrench or pliers, twist the flange with a horn or other gas wrench. The disk with this method is not affected, you can remove the normal, good disk. The method works even if the spindle lock is broken.
  2. We use two gas keys. The method does not require analysis of an angle grinder. Carefully break out the rest of the disc to get to the bottom flange. The first gas key clamps the upper flange, the second key – hook the bottom. We twist in opposite directions.
  3. Warm the nut burner. We heat the seated nut with a portable gas burner. The nut will expand due to heating and can easily be turned away.
  4. Saw the flange with a hacksaw. Some craftsmen prefer to saw a stuck flange with a hacksaw for metal. The method is barbaric – you have to buy a new nut.
  5. Lubricate threads with penetrating grease. Pour in nut onto WD-40 fluid. It penetrates into narrow slots and threaded connections. After a five-minute break, try moving the nut with a wrench.
  6. Cut the rest of the disc with a hacksaw. We break the disk with pliers, while it is possible. Remove the protective cover, insert a hacksaw into the slot for metal and cut out the remnants of the abrasive wheel. A delicate and reliable method. The angular grinder and rigid influences on the tool do not require analysis. The master must have patience, since the method will take up to an hour. The abrasive quickly erases hacksaw blades, they will need several pieces. The advantage is the guarantee for the angle grinder, there is no risk of breakage.

Video: how to change the disc angle grinder if the key is lost

What are cardboard pads for?

It is very simple and very important. To ensure that the flange is always easily unscrewed, a gasket must be laid between the abrasive disk and the flange. Or two – on each side of the disk.

These circles ensure that the flange does not get stuck.

Such discs can come complete with an angle grinder or you can cut them yourself.

For spindles of angle grinders, factories produce thin and thick abrasive disks, metal cutting wheels, nylon brushes. All these spare parts turn the angle grinder into a universal tool and reveal its capabilities from an unexpected angle. For example, an angle grinder turns into a sharpener. It is not difficult to change the disk, but the master must know about some features of the process so as not to get into a difficult situation.

Guaranteed production of a factory trimmer refill will inevitably require replacing the fishing line. Having a very rough idea of ​​how to fill the fishing line into the reel of the trimmer yourself, beginners are reluctant to take up this matter. However, with some skills, mastering this simple science does not present any difficulties, and the similar instruction presented below will facilitate this process as much as possible.

Preliminary preparation

First of all, for winding fishing line it is required to remove the reel (bobbin, spool) from the trimmer – specific actions will depend on the complexity of the configuration and the type of product itself:

  • Small electric trimmers with a working arrangement of the engine and the coil in the lower part, as a rule, have side keys on both sides of the bobbin. By pressing them simultaneously, the upper part of the reel, together with the internal contents for winding the fishing line, is disconnected, while the lower one remains on the trimmer. It is advisable to disassemble the bobbin on an even smooth place so that the spring included in the design does not pop out and is not lost;
  • Electric and gasoline trimmers with a curved rod without the possibility of installing a knife, as a rule, have coils with a special wing: in such designs, you should hold the spool in one position with one hand and rotate the locking reel on the wing nut with the other counterclockwise. After disconnecting the nut, the entire reel is removed.
  • Electric and petrol trimmers with the possibility of installing a knife on a straight bar (for example, Stihl trimmers) have a hole under the bobbin. For the motion of the rod to be stationary, a screwdriver or other suitable object is inserted into this hole and with a slow rotation, such a mutual arrangement is achieved when the screwdriver enters the hole and the bobbin is fixed. After that, the coil body scrolls clockwise (with the left thread) and is removed from the trimmer.

For the second and third cases, the coils, depending on the design, are disassembled in various ways. In bobbins with a lamb, a lamb is twisted, in coils with latches, latches-clamps are pressed and one part of the coil is released from the other. If the halves of the spool are threaded, it is enough to turn them by hand in opposite directions until they are completely unscrewed.

We carry out winding fishing line

Slowly completed disassembling the spool reel without losing its spare parts allows you to go to the main task – winding fishing line into the reel. Technological features of the design of the spool and the number of working antennae determine the sequence of actions.

Coil with one working antenna

The simplest option and a simple sequence of actions:

  1. The dimensions of the bobbin and the length of the original factory winding determine the recommended fishing line length for winding – 2 … 5 m.
  2. One end of the fishing line is inserted into the fixing technological hole located inside the spool.
  3. The fishing line is wound on the drum in the reverse direction of rotation of the spool on the trimmer product – as a rule, on the inner side of the bobbin an arrow indicates which direction the winding is going.
  4. A small section of fishing line is left free to bring it out – it is fixed in a specialized groove on the inside of the reel, designed to hold the winding when assembling the spool in working condition.
  5. The left end of the line is passed through the hole on the outside of the bobbin.
  6. The bobbin halves are assembled and put on the bar of the trimmer.

Coil with two working antennae

In this type of spools, you should determine the number of grooves for winding fishing line lying on the inside of the reel:

  • One groove – both antennae are wound together along one groove;
  • Two grooves – each antennae is wound on an individual groove.

For both cases, a 2-3-meter-long fishing line is taken. In single-groove reels, the fishing line is pulled into the through hole, its ends (antennae) are folded together and aligned, after which they are wound in the opposite direction of rotation of the bobbin on the side of the bar – the correct direction of winding is usually indicated inside the arrow. In the presence of fixing grooves, the ends of the fishing line are threaded into them or held by the fingers of their free hands, threaded into the through hole of the outer half of the bobbin, the spool is closed and attached to the bar of the trimmer.

The difference between winding fishing line in two-groove reels is that initially a piece of fishing line 2-5 m long is folded in half (to determine the middle bend), and the bend loop is inserted into a special groove between the grooves. Both antennae of the fishing line are wound each in its own groove, the fixation of the antennae and the reel assembly are similar to the one-groove variant discussed above.

The first implementation of this procedure may seem long and rather laborious, but with time and experience this task will be solved much faster and easier.

The video below will clearly show how to put the fishing line into the reel of the trimmer and wrap it correctly – this operation is not difficult and with some patience will certainly succeed:

Automatic reeling of fishing line

There is a variety of coils in which the automatic mechanism makes winding on its own – from the user it is enough just to properly fill the line. The fishing line is passed through the hole on the inside of the case, its antennae without winding is passed through the hole on the external case, the spool is assembled, and when the winding button is rotated, the line inside is wound up independently. In such a spool, it is impossible to make the winding incorrectly: the mechanism itself will determine the correct direction, since it can only turn in one direction.