The sharpness of a knife is one of the main parameters affecting the quality of wood processing. Besides, this characteristic also affects the degree of safety.
Often a person does not want to run around over and over again in search of a place where he could bring his cutting tools into proper condition. In this case, it’s time for him to think about making a homemade sharpening machine, which would solve the issue of the sharpness of planing knives once and for all.
The development of industrial equipment does not stand still. Happens all the time rapid growth requirements for speed and, most importantly, for the quality of material processing. In this regard, there is a need to create cutting tools with high parameters.
One of the main problems that arise during the work process is sharpening knives. This is what determines the basic capabilities of the machines and their suitability for use.
Homemade sharpening machine.
Depending on the tasks to be solved, such devices are divided into two types: universal and special. The first are sharpening devices for the surfaces of most cutting elements. They are equipped with a variety of devices that allow you to secure, install and sharpen knives.
All units are equipped with various equipment, which determines the degree of automation and control of the accuracy of the work performed. there are also different ones. These can be stationary devices or temporary ones that can be placed on any horizontal surfaces.
Despite the wide range of types of equipment offered, in order to save money, a knife sharpening machine can be made by hand.
Homemade units can, in some cases, even be more convenient than purchased options. This is due to the fact that the master independently decides what characteristics this device should have.
Although, of course, many models of universal devices allow you to choose the most suitable type of equipment that can solve the tasks.
Homemade knife sharpening machine
Most often due to two reasons. The first is the desire to save money. The second is to show your skill and do everything with your own hands exactly as your soul desires.
Drawing of the machine device.
For example, very often you may be faced with the need to put in order only certain tools. These can be drills, cutters, saws or jointing knives.
Each specific case requires a separate approach. Self-assembly The machine will allow you to make a convenient unit for working with certain elements.
Among other things, the presence of sharpening units will significantly save costs aimed at purchasing new knives or restoring them in third-party workshops.
If you need to professionally sharpen the tools listed above, then you should still give preference to purchased devices. They are more thoughtful and elaborate.
In addition, purchasing in a store guarantees that the device will solve the assigned tasks for a long time. You should also remember the degree of automation. Of course, professional devices use electronics that are simply impossible to make at home without the proper experience.
Option 1
Sharpening a planer will not only allow you to maintain the tool in in good condition, but will also save time on trips to other workshops.
One of the options for creating such a device is to use a motor with an abrasive wheel, emery cloth, or a sharpening device with a knife fixed in it.
Homemade machine for sharpening planing knives.
This device can be made partly from aluminum, metal and wood. In this case, bearings and guides are used, made from scrap materials, for example, pipe corners or others.
When the knives are level, they can be sharpened on a large abrasive stone. If this is not available, you should use sandpaper glued to a flat surface.
Depending on the requirements for the final result, you can vary the speed of this process. If there are dents, you must first use a belt sander, and at the final stage, treat the tool with an abrasive stone or a homemade one made from sandpaper.
The design features of the machines may also differ from each other. The first option is a device with a fixed base. Its angle of inclination can be changed, but otherwise it is in a fixed position.
The bar is attached to a rod, which is inserted into the loop of a movable clamp located on another rod. The disadvantage of this design is the “walking” angle due to the lack of rigid fixation.
The knife is installed using two steel plates fixed to a fixed platform. Having loosened the fasteners, insert the blade and clamp it. Then adjust the height of the bar so that the required angle is set.
Option 2
The second type of design provides a movable platform, as well as a magnetic holder. This option does not have the disadvantages of the previous unit. motionless in this device It turns out there is a frame with a bar that determines the angle.
The knife, in turn, is mounted on a movable table. The choice of holder remains with the master. You can use a magnetic type or a regular one, made of metal plates and “lambs”.
An important requirement for such equipment is the movement of the table with the cutting tool along a strictly horizontal surface. It is best to use a polymer or marble countertop.
The principle of sharpening knives on a machine.
As you can see, sharpening knives is not that difficult. If any problems arise, you can always take the help of training videos from the Internet. If all instructions are followed correctly, anyone can make such equipment.
Bottom line
Knife sharpening machine – necessary equipment in the workshop of every craftsman who works with wood. A timely solution to the problem of sharpening knives will not only speed up the process of processing the material, but will also save time and money.
Why go to other workshops if you can make the necessary equipment yourself?
Special machines are used for sharpening knives of planer and jointer types. The work can be done with your own hands; the machine can be assembled independently if necessary. Sharpening is carried out according to certain rules, several options are used. You need to be careful and not violate the technology.
Otherwise, knives for planes, jointers and planers will be poorly processed and will not be able to fully perform their functions. In addition to special equipment, sharpening stones can be used for sharpening, but a small sharpening machine that has cooling is best suited for the job.
Preparatory work
Anyone who has a plane or jointer faces the problem of sharpening knives. It is expensive to constantly buy new ones, especially since knives can be easily sharpened with your own hands using special machines or sharpening stones. If the jointer is used frequently, like other woodworking equipment, then it will be inconvenient to constantly send knives to the workshop for sharpening. It is better to assemble the machine yourself. To ensure that the jointer is always in working order, it is recommended to sharpen it at home. The easiest way to do this is with a regular sharpener. You only need to take a sharpener with low speed, its quality should be high. Water cooling must be available.
You can also use a sharpening stone, but it must first be leveled with a special device. Usually it comes complete with a small sharpening machine, so there is no need to additionally look for such devices. After the editing is completed, it is necessary to smooth the stone; a block is used for this. Sharpening a jointer knife without this step will be problematic.
What to do next? You need to set the angle of inclination. A special screw will allow you to correctly secure the blade relative to the position of the sharpening stone. Using this screw, you can subsequently set any angle of inclination of the knife. Next, take the holder that comes with the machine. A jointing knife is installed in it. Experts advise starting sharpening knives with a width of at least 13 mm. The length is not critical; if necessary, the knife holder can be rearranged to any position.
The knife must be securely fastened in the holder, otherwise sharpening will be carried out skewed, and this will worsen the quality of the jointer. How to properly secure a knife in a holder? While holding the blade in the desired position, tighten the clamping screws until they stop. To control the sharpening angle, you must use a marker; it marks the sharpened chamfer of the knife. It is with the help of this simple method you can easily monitor the quality and progress of work. The sharpening will be correct if the corner of the knife touches the stone. The stone must be rotated manually to determine if further adjustment is necessary.
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Sharpening process and operating rules
The holder moves to the right and left, movements are made relative to the sharpening stone. The blade should not be allowed to go beyond the edge. It is best to immediately install the holder 12 mm from the edge of the working circle. If sharpening is carried out, water cooling must be supplied. You will have to add water to the tank, you need to make sure that it does not run out. It is necessary to ensure that water does not accumulate on the floor near your feet. This is done for security reasons.
When performing work, you must ensure that the stone remains clean at all times, as it gets dirty quite quickly. A special whetstone is used for cleaning; it is recommended to carry out this procedure frequently, since only clean stones can be used for sharpening. The choice of stone itself depends on what kind of knives are used. Today, manufacturers produce jointing knives from soft or hard tool steel, so operating conditions will vary.
Sharpening takes approximately 20 minutes, then fine-tuning is performed. A special paste is used for this. After polishing, there should be no burrs left on the surface, otherwise the jointing knife will not be ready for use. The test is simple to carry out; a finished knife with excellent sharpening should easily and evenly cut a sheet of paper while hanging, leaving a neat cut.
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How to make a machine with your own hands?
To sharpen a jointer knife, you need to use special sharpening machines. This is especially important when jointers, planers and other woodworking equipment are used frequently. The sharpening machine is compact in size and can be installed even in a garage or small shed. summer cottage. Before starting assembly, you must prepare the appropriate tools that will be used during assembly of the sharpening machine:
- the table on which the work will be carried out;
- faceplate;
- vacuum cleaner;
- engine;
- casing for the machine.
You need to start assembling the machine by finding a suitable faceplate. It is one of the most important parts for a sharpening machine. All jointing knives are quite narrow, so they can only be sharpened using a faceplate suitable type. Then the sharpening work will be of high quality, safe, and fast. The faceplate takes up the bulk of the cost of all equipment. It’s more profitable to make a sharpening machine yourself; you won’t need expensive parts for it. Manufacturing will be quite justified if you have to frequently carry out woodworking.
You need to buy new faceplates; it is recommended to take American or German-made elements. They have the most high quality, and the cost fluctuates at 25,000 rubles. Next, you need to choose a motor for the future sharpening machine, it is best to take a 1-1.5 kW motor, you can even use a used element. Motors from old ones are excellent for the machine. washing machines, but first you need to make sure the engine is working.
The motor is mounted under the tabletop, the faceplate is mounted to the moving part.
It is imperative to provide a button to turn the machine on/off. It should be located within reach of your hand. The faceplate is covered on top with a casing, which is made in the form of a square. One corner of the casing must be cut off, since sharpening will be done on this side jointing knives with your own hands. A hole is made in the lower part of the tabletop; it will be intended for a vacuum cleaner pipe, with the help of which all contaminants that arise during sharpening will be removed. In addition to sharpening jointing knives, a similar machine can be used for other work, for example, for processing ax blades, saws and other tools used in the garden.
Jointer knives can be sharpened various methods. Special sharpening stones are suitable for this. However, you can assemble a compact sharpening machine yourself. It will be used to sharpen a variety of tools including saws and axes.
Owners of planing machines and electric planers periodically face the problem of sharpening cutting edges. A well-sharpened tool will ensure clean wood processing even at non-ideal angles and speeds. The easiest way is to sharpen knives and knife heads with your own hands using specialized equipment.
Knife sharpening is necessary
Planing knives require timely care because:
- blunt surfaces process wood poorly;
- when processing soft rocks with dull knives, the surface becomes covered with lint and unevenness;
- worn edges crumble;
- During planing with blunt edges, the engine and power units are overloaded.
Attempts to sharpen blades with your own hands using diamond stones, as a rule, give short-term results. Due to poor quality of editing, the blades have to be sharpened soon. Therefore, professional carpenters use only mechanical sharpening.
Types and designs of machines
The machines on the market are distinguished by the knife feeding mechanism:
- manually;
- automatically.
The machine for sharpening planing knives with manual feed consists of:
- grounds;
- abrasive stone;
- carriages for fixing the knife.
During processing, the cutter moves forward with the help of a handle. Transverse movement of the cutter is ensured by a flywheel.
Automatic machines differ in size and range of options. Mechanisms for industrial applications installed on a powerful cast iron frame. The carriage is equipped with a support. You can set the speed of movement of the blade and the thickness of the metal layer being removed. Industrial machines allow you to simultaneously sharpen several planer blades without changing settings.
| Corvette K-470 | WTG-163 | GA-630 | GA-850 | ZX-1000 | |
| Maximum length of knives, mm | 630 | 630 | 640 | 850 | 1000 |
| Abrasive disc diameter, mm | 100 | 150 | 125 | 125 | |
| Sharpening angle, degrees | 35…55 | up to 30 | 35…45 | 35…45 | Up to 30 |
| Engine power, W | 550 | 550 | 850 | 850 | 1500 |
| Dimensions, cm | 90 x 48 x 42 | 100 x 60 x 65 | 100 x 54 x 120 | 120 x 54 x 120 | 190 x 56 x 150 |
| Weight, kg | 75 | 60 | 112 | 125 | 250 |
| Add. intelligence | Equipped with an asynchronous motor, wet sharpening possible | Processes cutters, circular saws |
Wet sharpening possible | Can sharpen up to 4 blades, wet method | A wet method is provided, a cup-type grinding disc is controlled via a remote control |
Table 1. Characteristics of some models of machines for sharpening planing knives
Compact automatic machines for home and small workshops are designed to process one cutter in one go. They also provide speed control and automatic tool feeding.
Before starting work on any sharpening equipment, you should make sure that the frame is securely fastened. Vibration of the machine impairs the quality of sharpening and can lead to injury to the operator.
Basic rules for using manual feed equipment
Such machines are used for one-time work and for sharpening small batches of blades with your own hands, since the processing process is quite long.
- Before starting work, you need to make sure that the grinding surface is clean, without stains or streaks.
- The movement of the carriage should be smooth, without jerks or jolts. It is forbidden to stop it when the cutter approaches the sharpener.
- The faster the carriage moves, the lower the quality of sharpening. The optimal speed of movement is 5 - 6 m/minute.
- For proper sharpening, the range of motion of the carriage is important. During a pass in each direction, it should move 10 - 13 cm further than the end of the knife. This ensures optimal contact between the cutter and the sharpener, which must be broken before moving in the opposite direction.
Basic rules for working on automatic machines
- Planing knives can be sharpened dry or wet. In the second case, the blade is constantly washed with a stream of water. The wet method is gentler on the blade and more effective;
- Before processing begins, it is necessary to set the following parameters: sharpening angle, amplitude of carriage movement. The amplitude should be 15 cm greater than the length of the knife;
- The blades are carefully fixed in the mobile carriage with your own hands.
Homemade machine for sharpening planing knives
The design, made at home with your own hands, allows you to quickly and efficiently sharpen knives to one set angle. This will change the factory angle, so all blades will need to be re-sharpened. The quality of planing will not deteriorate, but may even improve.
To make a device for sharpening straight blades of planing, jointing and thicknessing machines with your own hands, you need:
- metal corner No. 50;
- round pipe with a diameter of no more than 50 mm;
- electric motor from a washing machine;
- powerful spring;
- bolt with nut;
- plastic handle (knob);
- Bulgarian;
- welding machine.
Making a machine with your own hands.
- Cut a corner about 50 cm long.
- We bend two pieces of pipe so that we get a stable stand for the corner, and weld the legs. The corner should be positioned vertically towards the master.
- At the left end, behind the corner, we attach an electric motor. It is placed on two points: a rigid axis and a powerful spring; The spring is tightened and released using the adjusting screw, moving the motor closer or further from the guide-angle.
- We put an abrasive wheel on the electric motor shaft.
- The engine is started by a switch located on the frame in a convenient location.
- We feed the tool using homemade vise from a piece of pipe 25 cm long, a pressure plate, a bolt with a nut and a knob. We clamp the knife in a vice and move it along the guide, holding it by the knob.
A cheap and easy-to-make clamp for sharpening jointing and planing knives. This is not the first instruction for making a homemade knife sharpening machine on the Internet, but I decided to make it to fill the gap between very easy sharpeners and very complex things.
In general, these are several guide rods, which allows it to be used, for example, for grinding back chamfers.
I tried to make a simple and cheap sanding machine with my own hands, and I feel that I succeeded.
To assemble a knife sharpening machine you will need:
- Drill and drill bits (approx. 0.2 cm and 2.5 cm)
- Vise
- Clamps
- Slats made of chipboard (or similar small-sized lumber)
- Dowels 1.25 cm (0.95 cm is too small, 1.1 cm is also not suitable, 1.25 cm is quite rigid)
- PVC pipe with a diameter of 2.5 cm (it could be smaller, but I had one)
- Coupling for pipe 2.5 cm
- 2 clamps for pipes 3 cm
- Steel cover
- A little (10-15 cm) steel wire
- 4 wood screws
- 2 sheet metal screws
- Wood glue
- Hot glue
The main disadvantage of this machine design is that the wooden holders/guide rod make it difficult to wash the sand off the grindstones. I had to wash them in the sink rather than in a bucket of water.
The second drawback is that the angle accuracy will, at best, be around +/- 0.7 degrees depending on the stone, even after calibration. This can be eliminated by using more advanced tools (such as a drill press or planer), but I didn’t have access to such things, and I don’t know how much they will help...
But enough abstract thoughts, it’s time to move on to implementation!
Step 1: Guide
Bend a piece of steel wire so that it has a through hole with a side of a little more than 1.25 cm. This is our guide - it fits into the holes that we will drill in the base and will control the location of the guide rod.
If the hole is slightly off-center, this is normal, perhaps even optimal, as will be explained below in the "Usage" section.
Step 2: Making the Base and Base
The base is easy to make. Some notes:
- The length should be reasonable. For example, if you will be using sharpening stones up to 30 cm long, you need to make the base according to at least(30 + 7.5 + 5) = 42.5 cm long. It's better to leave some extra, so I cut off 52 cm.
- The width should also be reasonable. There is no point in making it thinner than the lid (about 12.5 cm), it is better to make it wider, for me it turned out to be about 18 cm.
Designing the base is quite simple:
- Cut the pieces of wood to the required length
- Glue them
- After the glue has dried, attach the coupling with pipe clamps
- Fill the gaps around the pipe with hot glue to prevent play.
- Add a screw to keep the coupling from rotating
- Heat the steel lid with gas burner, apply hot glue to the wooden surface and press down
Everything is done, the base is just a piece of pipe with holes drilled in the appropriate places.
The screw controls the depth at which the pipe is immersed in the coupling so that the pipe does not get stuck and returns back every time.
The height of the holes can be approximately calculated using the equation shown in the diagram.
Step 3: Stone Holders
To ensure that the rod couplings give direction to the stone holders, drill a 1.25cm hole as close to the center of the coupler as possible so that they are in the same plane as the wide edges.
Just by eyeballing, I was able to get it to about +/- 1 degree, which was good enough for my purposes, but if you want to get the angle more precise, you'll need a drill press or drill jig or something similar.
Make sure you drill the holes exactly where you need them as they will be used to hold the stones. The important thing is that the distance from the hole of the guide rod to the bottom of the stone must be consistent for all holders; otherwise, wide variation is possible. I showed this in the photo.
In general, the smaller the stone, the less effort required. For example, the holder for my 30cm stone has a steel tongue that holds the stone in a foam pad, but the holders for 15cm stones simply fit the length.
Step 4: Use
The design has several assumptions, which together can give a couple of degrees of deviation. To level, you need to press the stones against the steel plate and figure out how much base movement is required.
That is, if there is a deviation of 1 degree, and you need to sharpen at an angle of 25 degrees, insert the guide into the hole at 26 degrees.
Press the jig onto a table or other surface and use. You can press the knife against additional support if necessary.
This is for those who have problems sharpening knives for wood planers.
The quality of wood processing (and not only wood) depends on the “sharpness” of the knives and not only the quality of processing, but also the safety of working on such machines. There are seven such machines in my “arsenal”. Every time I get tired of “searching” for where to sharpen. And you won't find much. The sharpening process itself does not tolerate “quickness”; the knife can simply be “burnt”. This takes a lot of time and it is advisable to do it at home. The machine must be automatic or at least semi-automatic. In order to remove as much tedious work as possible from the machine operator.
As always in my practice, I use, first of all, to make from “what is.” Reduce costs to a minimum, while the quality of work and the future manufactured product should not suffer.
The result is this “unit”. I am satisfied with the operation of the machine, the problem of sharpening knives has been resolved.
The power engine was borrowed from an unnecessary pumping station, approximately the same modification.
Its parameters are quite acceptable for this machine.
The machine frame was welded from profile pipe(20x40) and screwed it with self-tapping screws to a wooden base, thereby increasing the rigidity of the structure. Which is very important. I welded a guide profile of the same size in the center. It serves to direct the movement of the sharpening unit carriage.
The base of the sharpening unit is made of strong metal from railway rail chocks. Found on the farm.
After appropriate processing, I installed a guide plate on it, on which I secured the electric motor at three points. One of them is adjustable. The guide plate, relative to the support plate, is movably mounted on two piston pins from the Muscovite, the rollers (guide shafts) fit exactly from the UAZ gearbox. To supply the whetstone to the part (knife), there is a screw with a fine thread.
The entire unit moves along guides on sealed ball bearings, 4 support and 4 guides. This must be done very accurately, since the backlash here is not acceptable.
The emery itself (stone) is plate-shaped, which allows sharpening according to the rules for sharpening such knives.
The knife is fixed in a special device that can change the sharpening angle. For a planer sheath it should be 45-60 degrees. To attach the knife to the device, I used canopies from furniture sets.
There are two adjustment screws at the bottom to adjust the knife when sharpening, along the gap between the knife plate and the sharpening stone.
The fasteners turned out to be reliable and inexpensive.
After the adjustments, turn on the emery and begin to move the unit along the guides, from one end to the other of the bed. At the same time, gradually tighten the feed screw. But don't overdo it, otherwise you might burn the knife.
Naturally, this process takes a lot of time and I had to do this part self made, automate. I found in stock (as many as three) an electric motor with the required speed. I came up with a “power supply” from 220 V. (there it has 127 V.) and most importantly, reversible switching of the engine. Installed limit switches and relay,
Val, to move the carriage I had to order a kit from the Chinese, which suited me quite well. The set consists of a shaft (60 cm), bearings, a self-aligning coupling, and a guide sleeve.
