In modern retail outlets can be purchased jig boring machine for the processing and creation of holes with the exact placement of Cartesian axes, light milling, drilling, marking and accurate measurement of linear dimensions, especially the spacing.For treatment of holes and inclined holes that are defined in the polar coordinate system to the machine, you can purchase a turntable.However, prices jig boring machines, "bite", so you can always try to get the machine with their own hands, after referring to the construction and operation of the machine.
- design jig boring machines
- The principle of coordinate-boring machine
- cutting tool for jig boring machines
- Traffic management table and slide
- Making Jig-boring machine
- Carriages of typewriters
- Drive tools and table
- Homemade kardanchik
- Threaded shaft
- Floating bronze nut
- calculation speed and feed rate
- Some recommendations
design jig boring machines
Performs coordinate-rastochnye machines particularly hard, with careful balancing of rapidly building blocks and components to reduce vibration and smooth motion.Machines require special conditions of use, so they are usually installed in isolated termokonstantnyh rooms where constant temperature is maintained at 20 degrees above zero Celsius ± 1gradus.
main parts Single Column Jig-boring machines are stand, boring head, rack, table slides.Double column jig boring machines have a rack frame, boring heads, desk and Traverse.Cutting tools and products for jig boring machines are mutually move in rectangular and polar coordinates.
Stand acts base machine.It has two blades and a T-shaped guide, which is made moving the slide.Located on the frame and remote control mechanism set of coordinates.Rack support structure is the rear part of the frame.On the rack are placed the following elements: gearbox, power rails and a casing V-belt transmission.
The headstock spindle sleeve is located.Lowering and lifting spindle head takes place by rotation of the flywheel.Desk is designed for installation on a workpiece and move them in the direction of the axis X, which is made by moving the table on the rails.The sled serve for movement of the table and the workpiece, mounted on it, in the direction of Y axis while moving the transverse slide guide frame.
precise measurement of positioning the carriage and the table is carried out with the aid of optical devices and high-precision glass ruler.The range table has a thousand divisions, and slide rule - 630. Each division equals one millimeter.Optical unit carriage and the table are the same.Also koordinatnor boring machines are equipped with a variety of devices and tools for boring, drilling, milling, tapping and line marking.
The principle of coordinate-boring machine
The principle of jig boring machines is as follows.The workpiece is fixed on the surface of a table, spindle boring heads boring tool is located.Depending on the height of the workpiece, the boring head and traverse set at a certain height and fixed.
at specified coordinates of the spindle occurs by moving the table in two directions that are mutually perpendicular, when working on the single-column jig boring machines, or moving a table along the guide rails in the longitudinal direction and moving the boring head by the boom in the transverse direction in the case of worktwo-post gantry machine.
features of the device coordinate boring machine, its installation and maintenance are:
- presence corrective devices that compensate for the error of pitch;
- use of optical devices to reference coordinates;
- use of roller guides who take mass slides, products, table and cutting force;
- considerable precision assembly machine components, machining and high quality of work;
- good resistance to vibration and a massive foundation.
process of spindle rotation is derived from the regulated electric DC motor through a three-stage gearbox.The boundaries of each stage is infinitely adjustable spindle speed in the range 50-3000 rpm.The procedure for making the spindle is also infinitely variable friction variator.There mechanism shutoff spindle automatically at a predetermined depth, and provides for a mechanical clamp table clamp and hand headstock.
cutting tool for jig boring machines
cutting tool attached to the spindle hole.When working on jig boring machines are most often used boring cutters - scoring, communicating, and threaded grooving, also use drills, reamers, core drills, cutters and taps.The most widely got boring tool that is shaped cantilevered boring bar with rod cutter enshrined in it.
facilitates setup tools in the application of cutting tools, inserts with micrometer regulation size.Boring heads are boring bars, cutters are located on diametrically opposite sides.Designed for trimming cutters, cutting part of which is carried out at an angle.On jig boring CNC boring assembly is usually installed tool that includes a unified shank, head and extension member.
Boring boring cylindrical holes made bushing cutters, pruning the ends of the Greatest size - Scoring tool for work, the internal cylindrical surface of a large diameter - boring cutter, which is mounted on the faceplate jig boring machines in the mandrel.
main movement holds the tool that rotates with the faceplate.Similarly handled short cylindrical surface.Internal grooves and end surfaces of details necessary to process the relevant incisors, which are fixed in a radial caliper.
Traffic management table and slide
movement of the workpiece in a position that is required to process the next hole, produced by controlling the movements of the slide table and manually or with the commission of a preliminary set of coordinates.
Traffic management table to manually by turning the knob from the zero position in the division, which indicates the speed of the table in millimeters per minute.Spin the table takes place at the turn knob, with red light goes out and lights up green.Then the table is moved at a preset speed in the direction that corresponds lettering and arrow.The new position of the table are counted roughly the pointer and a scale ruler.
When approaching the table to the desired position of its movement speed is recommended to reduce turning the switch off and then placing against a fixed scale of zero risk regulator.Manage transverse movement of the slide on a vertical jig boring machines can be similar to using a controller as control the movement of the table.
Predialling required amount of movement of the carriage and the table to reduce the time to fit them in the right position.The direction of movement of the table set a special switch.The switch is turned to the left to move the table to the left and right to move the motion of the table to the right.
required amount of movement of the table will be recruited by rotating the limb.Table travel per revolution is reduced or increased by 100 millimeters.And dividing by the number of scales indicate the progress of the table in hundredths of a millimeter, and help set the course of the table, keeping to the millimeter.The countdown turn table is always made from the zero division limb.A preliminary set of stroke and direction of the slide make another limb and switches that are arranged in a similar way.
Making Jig-boring machine
Many owners dream of jig boring machines with CNC.The basis of any CNC machine performs coordinate table that moves the workpiece and the tool in three dimensions -Forward-back, right-left, up and down.The table is a plate of duralumin, measuring 260 by 340 millimeters, below which are fixed two parallel rails.
main part of the coordinate table are guides that provide easy and precise movement relative to each other moving parts.In practice improvised machine tool usually use round rods and bushings that slide on it, such as a jet and dot matrix printers or scanners.But there are many challenges that await anyone who will install them on the machine-related wear and tear.
machines operate in the harsh environment of metals, dust and chips are deposited on a greased rod and under bushes.In addition, there is no hope to achieve high accuracy.Finished guides differ only at the cost of space.The most primitive "rail" with a cart, two feet long, is worth more than $ 200.And for the good of the machine must be at least 6 guide, so thoroughly have to spend.
Adjustable gap in the guide with the four screws that are screwed into the side of the channel at the level of the rails.To u on the sides attach two braces of steel plate, thickness of 4 mm, and on top - a guide.Vertical guide attached perpendicularly to the movable part.All moving parts are in motion stepper motors through the drive.
carriages from typewriters
Thus, the search for the necessary equipment to use as a guide led us to the predecessors of computers - old mechanical and electric typewriters.They are necessary only carriage.Removed carriage is very simple - push it to the left, the right one spun the nut that holds the entire device, and then shift the carriage to the right and spun to the left the same nut, then lift the carriage and disconnected cotton leash of her return.
then need to dismantle and remove the guide carriage relsy- long black metal rods.It is necessary to act carefully, because when removing the rail will sleep balls or rollers that provide easy sliding carriage.Need these rods, rollers and balls, the return spring of the carriage and the rail unit, which is located on the movable part of the carriage.
What good are the details?The carriages of the old printing machine made of stainless steel.These rails are subject to wear very slowly.Almost all of the carriage can be used whole or in part by cutting the desired portion of the carriage, if the machine is large.Easily adjustable carriages bearing clearances, this is due to the design of the carriages.Also today, typewriters are not deficient, it displaces the computerization of their offices, and they are written.
If you plan to make your own hands jig boring machine small size, you can use half of the carriage, which will serve as a guide for the desktop.The second half can be used as a guide for the movement of the tool along the transverse coordinate Y. To move the tool vertically using another part of the carriage.
Drive tools and table
Nothing complicated in the drive of the tool and the table is not - each axis stepper motor movement, homemade kardanchik, running shaft bronze split nut is attached to the movable part of the carriage.Screw necessarily apply, you can take and the timing belt, but discrete movements and accuracy will be better than an order of magnitude with the screw.In addition, it provides high tractive effort.
It is best to take the engine bearings and subject him to finalize, if it is necessary to eliminate the longitudinal play of the shaft.To the rear side of the motor for this purpose to fasten a square plate made where near done recess and inserted between the shaft and the plate of the ball bearing.When the plate is attracted to the back of the motor, the ball will put pressure on the shaft of the engine and do not give him a play.
Make homemade kardanchik of bronze or steel bushings, an inner diameter equal to the diameter of the first, making the motor shaft and the lead screw.Then put on the motor shaft sleeve drill through the through hole, whose diameter is equal to the diameter of the needle from a small needle bearing.Insert the sleeve shank spindle, turn the sleeve on the motor shaft by 90 degrees and drill a second through-hole.
Remove the sleeve, increase its inner diameter of 0.5 - 1 mm.Then again, insert the motor shaft and the shank threaded shaft Press fit bicycle spokes or segments of the needle bearing.To saw off the sleeve bore so as not to fall out of the needle.Do not forget to kardanchik drip a few drops of oil.With a suitable drill diameter play in kardanchike be only a few microns, which is suitable for most operations.
Khodov shaft is a simple steel threaded rod that is cut on it.You can buy it in the household goods, and you can try to cut the thread.For small enough machine shaft diameter of 6 mm, for large - about 8-10 millimeters.Pitch should be standard.
With self-cutting bars take longer than 100-150 millimeters than necessary, and cut at the entire length of the thread, except for a tail - the last 10 millimeters.Then measure out the desired length of the shaft from the start of the thread, cut an extra piece.Usually
thread leveled after 100 millimeters, and further nut will go smoothly.Please note that it is not always the thread pitch will be exactly the same as specified, and at considerable length of the screw nabezhit small error.Thus, the length of the thread turns 400 in increments of 1 millimeter is not always equal to 400 millimeters deviations will reach 2 millimeters.
Floating bronze nut
In order to create a split nut is recommended to take a rectangular bronze brusochek in which the machine with a horizontal table, drill a hole for the thread, the thread and cut the first tap, with a diameter that is equal to the diameter of the threaded shaft.Then lubricate the threads of the nut and shaft nut screw several times before the end of the threaded portion of the shaft until the nut does not turn easily.This helps to minimize backlash in the nut.
To reduce the gap even more, it is necessary to make a cut across the nut thread, but not completely, then set the adjustment screw to secure the nut a little tightness.After this must be secured to the movable part nut and the motor with a fixed shaft and screwed kardanchikom - on the fixed part of the carriage.It is mandatory to provide the required ratio of the motor shaft and the hole in the slotted nut.
calculation speed and the amount of feed
After making supply unit need to figure out how far it will travel in one step.Spindle large jig settlement machine is different in increments of 1 millimeter, and the rotation angle of the stepper motor to step up 7.5 degrees.Divide 360 by 7.5 and you will get the number of steps per revolution.