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9 Points about Machining with Drill Press Skills and Precautions Machining with Drill Press is usually used to process holes with small sizes and low precision requirements, such as cooling water holes and threaded bottom holes. In addition to drilling, the drilling machine can also perform processing such as reaming, reaming, tapping, countersinking, and scraping. Machining With Drill Press
The ground drill bit will have a larger relief angle at the drill core, which is conducive to drilling. When sharpening the edge, the angle of the cutting part of the drill bit should meet the requirements, the two main cutting edges should be equal in length, and the top angle should be equally divided on the center line of the drill bit. Most of the eyes are checked during work, and the cutting part of the drill bit is erected upwards, and the eyes are flat to watch the cutting edge. Because the two cutting edges are in front of each other, there will be parallax, and it often feels that the left edge (front edge) is higher than the right edge. Therefore, the drill must be rotated 180° before the visual inspection. In addition, trial drilling can also be carried out on machining with drill press
e. Workpiece Clamping of Machining With Drill Press: The workpiece can be directly fixed with a pressure plate and screws. The screw should be as close to the workpiece as possible so that the pressing force is greater, and the pad iron should be slightly higher or equal to the height of the pressed workpiece. If the surface of the workpiece has been finished, a copper sheet should be placed under the pressure plate to avoid imprinting on the workpiece. When machining with the drill press, first start the drill press, and the tip of the drill bit is aligned with the intersection mark. Feed the tool manually during trial drilling, and when the diameter of the hole is about 114in, lift the drill bit again to check whether the center of the drilled hole is on the cross point of the marked line. If the position is correct, continue drilling until it is almost the same size as the diameter of the drill bit, lift the drill bit, and check again. In addition to checking whether the position is correct, it also depends on whether the drill bit is vertical. After everything is correct, the pressure plate and screws can be used. Lock the workpiece tightly and drill to the desired depth or through. However, if you drill through holes, you must leave a space for the drill bit, otherwise, the drill bit will damage the work surface. And if the drilled hole deviates from the center, it must be corrected. Generally, you only need to put the workpiece over a few. If the drill bit is large or has a lot of eccentricities, use a sample punch or a sharp chisel on the opposite side of the drilled crooked hole to gradually move the deviated part to the right. When machining with drill press, whenever the drilling depth of the drill bit reaches 3 times the hole diameter, the drill bit must be lifted to remove iron filings, prevent excessive wear or breakage of the drill bit, and affect the roughness of the hole wall. When drilling a large-diameter hole, because the cutting effect of the drill tip is very small, it should be processed twice this time, first drill a small hole, expand the guide hole of the drill, and then use a large drill. This can save effort, and the accuracy of the hole can be easily guaranteed. Generally, holes exceeding φl12in can be drilled two or more times, and each time the diameter is increased by 1/4in.
g.To drill and tap the 1/4in NPT throat on the inclined surface, first use a φ1/2in 45° head countersink to mill out a full φ1/2in the hole, and then match the drill bit and tap that should be drilled. h.Reaming of Machining With Drill Press: According to the method of use, reamers are divided into machine reamers and hand reamers. In the previous process of reaming, a certain machining allowance must be left for processing during reaming. The processing amount of the reamed hole is appropriate, and the wall of the reamed hole is smooth. If the allowance is too large, it is easy to wear the reamer, affects the surface roughness of the hole, and polygons will appear. The reaming allowance should be determined according to the size of the aperture, generally between 0.2 and 0.4mm. When the reamer is working, the friction of the hole wall behind it is very large, so cooling lubricant must be used when reaming. i. Ream the knife by hand, and the work clamping must be correct. After the handle of the reamer is installed, insert the reamer into the hole and correct it with a square. Hold the handle with both hands, apply a little pressure, and twist in a clockwise direction. Machine reamers and hand reamers are also strictly prohibited from being reversed. If there is difficulty in reaming, it is still necessary to lift it clockwise, find out the cause, and deal with it in time. |
