Miter box- this is a tool device in the form of a U-shaped tray with side slots for a saw, designed for sawing slatted material at a given angle.
When installing floor or ceiling skirting boards, door trim, laying electrical wiring in cable ducts or furniture manufacturing, there is a need to saw the material into pieces of a given length at a right angle or a 45 degree angle. You can, of course, cut the material along the line drawn using a square. But in this case, the work requires care and it is easy to make an irreparable mistake.
To increase the productivity and quality of sawing, a simple device called a miter box was invented. In the photo there is a miter box made of industrial plastic, with which hand saw You can cut slats, bars, corners made of wood, chipboard, MDF, plasterboard, plastic and other soft materials at an angle of 45° and 90° with sufficient accuracy.
It is enough to mark one point on the rail that needs to be adjusted to size, insert the rail into the miter box so that the mark is on the line of the guides, and hand hacksaw, insert the blade into the slots, cut the strip. The miter box will not allow the saw blade to move to the side and the end of the rail will be the required one.
Industrially produced plastic miter boxes have a significant drawback: due to the larger width of the guide slots and their rapid wear by saw teeth, the accuracy of the angle is low and gaps up to one millimeter wide often remain at the junction of the baseboards or platbands. There are high-precision miter boxes on sale, which even provide the ability to change the angle within any limits, and there are clamps for fixing the material being cut. But they are very expensive, and for one-time repairs in an apartment it does not make sense to purchase such a device. Moreover, a high-precision miter box can be made with your own hands in a couple of hours from scrap material.
To make a homemade miter box, you will only need a couple of metal, preferably aluminum, plates 1.5-2 mm thick and a board for the base of the miter box about 10 cm wide made of wood, chipboard or plywood.
Making a miter box with your own hands
The dimensions of the parts are not important. But the wider the board, the more accurate the cut will be and the ability to cut wider slats. The width of the miter box should not exceed half the length of the hacksaw blade, otherwise sawing will be inconvenient.
Making a miter box begins with cutting out the parts and marking them. In the middle of the board of the base of the miter box, a straight line is applied at right angles to the side walls. A perpendicular line can be drawn using a special square or taking any sheet of paper folded twice.
From the ends of this line, at a distance of half the width of the board along its length, marks are drawn, which are connected by line segments with a marker. The result was lines located at an angle of 45˚ and 90˚ relative to the longitudinal side of the board. But the main one on the base is the perpendicular line, relative to which the side walls of the miter box will be oriented during installation.
On both side walls, in the middle, as well as on the base, first apply along one perpendicular line. From them, at a distance of half the width of the base, for me 5 cm, two more parallel lines are drawn. Marking is done using a ruler or caliper. Here you need to try to draw the lines accurately, since the accuracy of sawing the material will ultimately depend on this. It should be noted that the wider the base board, the higher the cutting accuracy will be.
Next, you need to draw a section of each wall that will be adjacent to the base of the miter box. Since my basis is from Chipboard thickness 18 mm, then you need to draw a strip 18 mm wide. Draw a line in the middle of this strip and mark points on it at an equidistant distance from each other for drilling holes for self-tapping screws.
To prevent the drill from running away at the beginning of drilling, small indentations are made at the designated points with a core, then holes with a diameter of 4 mm are drilled and if the screws are countersunk head, then it is better to make a countersink, although this is not necessary.
The next step is cutting grooves in the walls of the miter box. The strip must be fixed in a vice or using clamps on a table and cut along the marked lines with a hacksaw. The middle line is sawn at an angle of 90˚, and the outer lines at an angle of 45˚. High precision is not needed here, but it is advisable to do this work carefully. The cut should only reach the line where the walls are attached to the base of the miter box.
Since the chipboard base is soft material, then self-tapping screws with a rare thread pitch are best suited for fastening the walls. Although you can use any that are on hand, 25-50 mm long.
After making the base and walls, you can proceed to the next step, assembling the miter box. To do this, you need to accurately align the middle cut in the wall with the perpendicular line on the base of the miter box, pierce the hard wall of the side edge of the chipboard with an awl and tighten the screws. It is better to drill a hole in plywood with a diameter equal to the diameter internal thread self-tapping screw to the depth of its length.
It is convenient to assemble the miter box by securing its base with clamps to homemade table for repair. Thus, the lower end of the side wall can be easily aligned with the lower surface of the miter box base.
During a test sawing in a miter box at an angle of 45˚, it turned out that the hacksaw blade moved tightly and rubbed against the walls of the cuts. I had to sharpen them a little with a flat file.
I made the side walls of the miter box from aluminum alloy, but they can be made from plywood or any other dense sheet material. The thicker the side walls, the longer the miter box will last.
Examples of work using a miter box
Quality sawing rack material The miter box helps me all the time. For example, when laying electrical wiring, it may be necessary to cut the cable channel at a right angle and at an angle of 45˚.
To do this, it is enough to place the cable channel on the base of the miter box, resting it against the far wall and, using a hacksaw for metal, accurately saw off the required section.
After removing burrs from the walls at the cutting site, the parts fit together with virtually no gap.
The miter box is also great for sawing foam ceiling plinths. Thanks to the fine teeth of a hacksaw file, the end of the plinth is ready for joining without additional processing.
In the same way, the ceiling plinth is sawn at an angle of 45˚. It can be rotated in any way and create a tight fit, both on the inside and external corners walls
A miter box is also indispensable when installing floor plinths. You can not only saw off the required lengths of the plinth, but also, when adjusting, shorten the plinth even by one millimeter, which is almost impossible to do without a miter box.
As you can see, the miter box is necessary equipment for getting High Quality work with minimal effort. I advise you to definitely buy or make a miter box with your own hands; it will be useful not only when renovating an apartment. Using a miter box, you can make a frame for a photograph or painting, or saw through a plastic tube when performing plumbing work. It’s even difficult to list all the cases of using a miter box by a home craftsman.
Manual circular saw In the standard version, it is extremely difficult to make precise cross-cutting of the board. Getting the perfect cut in accordance with the markings allows you to simply homemade device, easily made from scraps in your home workshop.
The saw is designed for perpendicular cuts of boards ranging from 100mm to 250mm wide in 50mm increments, but can be easily modified to suit your needs.
How does a handheld circular saw attachment work?
The device in question is extremely simple and consists of only a few parts: a base for the saw, a guide rail, a thrust block and an eccentric clamp that ensures reliable fixation even on lumber that has been loosened with slight deviations in width.
The homemade product is very easy to use. First, markings are made on the board.
Then a homemade device is installed on top, the lower stop of which is pressed against the edge of the workpiece, and the right edge is aligned with the mark.
Now all that remains is to place the circular saw on the base and make the cut, pressing the edge of the sole against the guide side stop.
The result will be perfect straight cut, exactly repeating the markup.
With this device it is convenient to make many cross cuts when you need to frequently move the tool to a new cutting line, for example, when making grooves in beams. It is also useful if it is necessary to reduce the length of the workpiece by several millimeters, and it will cope with this task no worse than a miter saw.
How to make a device with your own hands
The cutting device is made for a specific model of power tool. On your circular saw, measure the distance from the engine to the bottom plane of the sole and subtract 5 mm. The result obtained is the height of the guide stop.
Prepare a plywood base with right angles and wooden slats with parallel edges.
Measure the distance from cutting disc to the edge of the sole.
Add an allowance of 6–10 mm and install a guide rail at this distance from the right end of the plywood. Secure the plank with countersunk screws, ensuring its strictly perpendicular position.
Screw with reverse side thrust block and fix the device on the workbench.
Cut the plywood to the final width with a circular saw, creating a reference edge for precise positioning of the jig along the markings.
Draw a template for the cam clamp cam on paper.
Mark the piece on 10mm plywood and use an awl to mark the center of the drill hole for the bolt.
Cut the workpiece with a jigsaw.
Make a washer with a diameter of 50 mm from the same plywood using a ballerina extendable wood drill.
Sand the workpieces and select an M6 or M8 furniture bolt with a mustache (or with a square headrest), a handwheel nut, a washer and a bushing. The latter can be made from a tube of suitable diameter. The length of the sleeve is the total thickness of the base, lever and plywood washer.
Make holes in the base with a drill according to the diameter of the bushing, which serve to rearrange the eccentric clamp according to the width of the board being cut.
Assemble the eccentric mechanism: insert a bolt with a sleeve on top, and install a wooden washer, the cam itself and a steel washer from below. Tighten the parts with a nut.
Stick with inside stop with a strip of sandpaper to prevent slipping when the eccentric is locked, which can occur when the device is fastened to a smoothly planed workpiece.
The clamping system of this device has a stroke that ensures fastening on boards with a spread of approximately 10 mm in width. If you need to cut or trim pieces of a different size, simply place a wooden block in front of the stop beam.
If desired, the potential of the considered device can be expanded by adding a cutting angle of 45°. To do this you will need to slightly increase the dimensions. support platform and install the second thrust block at this angle.
Among large quantity construction tools there are all kinds additional accessories, designed to make the hard work of craftsmen easier. Those involved in carpentry are familiar with this slightly strange name - “”, which means an assistant tool for cutting boards or any other profiled material at a structurally fixed or independently determined angle. For ideal design of internal and external projections, the angle is usually 45°.
The material intended for sawing at an angle can be different: skirting boards, door and window casings, baguette materials, slats, cornices, etc. The miter box is rigidly fixed on the workbench, the material is sometimes pressed with a clamp - such a device is safe and convenient to use.
Classification division
Despite the apparent simplicity of execution and use, the miter box has its own classification:
- simple– the most popular modification is a form of industrial or self-made, most often plastic, with several side slots that serve as guides for the saw. Designed for sawing slats, bars, corners made of wood, drywall and other materials at angles of 45 or 90°;
- rotary– with a hacksaw from 290 to 600 mm mounted on a metal or plastic base with the possibility of its rotation from 15 to 135°;
- electric– a tool that is an electric saw mounted on a rotating base.
Rotary and electric miter boxes are professional tools , designed for sawing in two planes. The strongest and most durable are those made of hard wood and metal (from aluminum alloys) products. It is recommended to use metal miter boxes for molded parts of small thickness, wooden ones for small volumes of work.
How to use a miter box?
Mastering the miter box is not at all difficult. In addition to the tool itself for correctly organized work required:
- a hacksaw for direct cutting of wood or plastic coated with veneer (for a hacksaw, it is important to take into account the pitch of the teeth);
- assembly knife for cutting foam plastic;
- ruler and pencil for notches and marks in the initial stages of development;
- sandpaper for treating surfaces after cutting in order to remove irregularities, roughness and burrs.
Sawing slatted material
Often, when laying external or internal electrical wiring, as well as in other cases, it is necessary to properly cut the slatted material (for example, cable duct) at an angle of 45 or 90°.
For this purpose, a rail or cable channel is fixed in the body of the miter box with an emphasis on the end wall and a hacksaw for wood or metal (depending on the material of the rail) accurately makes the desired cut.
After carefully removing possible irregularities and burrs from the cutting site, the parts will fit together almost perfectly, without the slightest gap.
Jewelry fitting
The miter box successfully copes not only with sawing at the desired angle, but also with careful millimeter adjustment of the material. Without rigid fixation of the material in the mold and grooves directed at a certain angle cutting part the hacksaw will “walk” and the cut will not be made accurately, but only with some approximation. Only using a miter box will help remove the “extra” millimeter of length.
Working with ceiling plinths
Installation foam baseboard into the tool is produced in the same way as rack material. Depending on the type of cut required, the hacksaw moves along the appropriate grooves. Thanks to the frequent step of the cutting part of the hacksaw, the cutting area of the baseboard will be smooth and without additional processing.
For a tighter fit both in the internal and external corners of the walls, the plinth in the miter box can be rotated in a convenient way.
Things to remember:
- to avoid serious cracks at the joints, before starting work, you should check at what angle the planes of the walls meet;
- For internal corner The surface of the plinth adjacent to the wall should remain longer; to finish the external protrusion, on the contrary, the edge adjacent to the wall becomes shorter;
- for adjustment, especially for beginners in the construction business, it is recommended to leave 3-7 mm: imperfectly smooth surfaces and the curvature of the plinth will “eat up” this margin;
- For quality cuts variety of materials, it is important to use only those intended for your type cutting tool;
- the junction can be covered by external or internal elements decor - for example, corners. In this case, it is advisable to cut at an angle of 90°.
Ceiling plinths carefully sawn on a miter box, without unsightly finger-thick gaps, will effectively complete the framing of the surfaces and give the room a finished look. With the acquisition of some experience, working with a miter box will allow you to design the most complex building construction.
Other uses for miter boxes
The miter box is a tool not only for construction and repair work, cutting cable ducts and ceiling plinths. It is useful wherever precision and accuracy of cutting is required, for example, for manufacturing baguette frame when decorating a photograph or painting.
Whatever the purpose of the miter box, when cutting using it there will be much less waste than with manual measurements and cutting “on the knee”.
A miter box is a tool for cutting workpieces at a certain angle. These blanks can be made of wood and plastic. Most often it is used for cutting door frames, skirting boards, wooden blocks.
You won’t be able to manually cut a block at an angle of 45 degrees, which is why such a tool was invented - a miter box.
They are different widths and length, depending on the size of the workpiece.
For example, the photo below is the most common one.
One of inexpensive models, with its help you can cut workpieces measuring 65mm in width and 35mm in height. If the workpiece is higher, then it will no longer be possible to insert the saw into the grooves.
It is possible to cut at an angle of 45 and 90 degrees.
This is suitable for small thin bars and narrow trims. The kit includes a simple saw with a small, non-hardened tooth.
This option is quite suitable for infrequent household work; the plastic is quite flimsy.
Approximate price for 2013 – 120 rub.
If you use a miter box constantly, then take better option more expensive, but better quality. 
The miter box itself is already noticeably wider; you can cut workpieces 100mm wide and 52mm high. Unlike the first option, it is possible to cut not only at an angle, but also at an angle, 
those. It will be possible to make an angle in a different plane. The plastic is much thicker, making the body more rigid and reliable. For convenience, it can be attached to the table with bolts or screws. There are two holes for this.
There are markings on the body for convenience.
The kit includes a saw with a hardened tooth, a powerful rubberized handle that fits perfectly in the hand. To prevent the canvas from bending, there is a stiffener on top of it.
Estimated cost 350 rub.
Another option. WITH eccentric clamps, which allow you to fasten workpieces of any shape, not just flat rectangular ones, but even round ones. 
There are angles of 22.5 degrees, 45 and 90, and you can also cut at an angle.
Width 110mm, height 75mm – for quite serious workpieces.
Made of thick plastic, can be mounted on a workbench.
The saw is not included, you will have to buy it separately, it costs 150 rubles.
The miter box itself is 300 rubles.