欧美人妻精品一区二区三区99,中文字幕日韩精品内射,精品国产综合成人亚洲区,久久香蕉国产线熟妇人妻

Góc trên cùng c?a m?i khoan xo?n th??ng là 118 °, c?ng có th? ???c s? d?ng là 120 ° Nhìn vào nó. Bit mài ch? y?u thành th?o các k? n?ng sau:

the edge shall be leveled with the grinding wheel surface

Before grinding the bit, the main cutting edge of the bit and the grinding wheel surface shall be placed on a horizontal plane, that is, when the edge contact the grinding wheel surface, the whole edge shall be ground. This is the first step in the position of the bit relative to the grinding wheel. Set the position and then slowly lean on the grinding wheel surface.

The Must-know Manual Sharpening Technique of Twist Drill 2

the axis of the drill bit shall be inclined out from the grinding wheel surface by 60 ° Angle of

This angle is the front angle of the bit. The wrong angle will directly affect the size of the top angle of the bit, the shape of the main cutting edge and the angle of the horizontal edge. This refers to the position relationship between the bit axis and the grinding wheel surface, taking 60 ° OK, this angle is generally quite accurate. Here, the relative horizontal position and angle position of the drill edge before grinding should be paid attention to. Both should be considered. Do not neglect the setting angle for the purpose of flattening the edge, or ignore the blade edge for the sake of setting the angle.

grind back from the edge

After the edge contacts the grinding wheel, it is necessary to grind from the back of the main cutting edge, that is, the edge of the drill bit first contacts the grinding wheel, and then slowly grind down along the whole rear blade surface. When the drill bit cuts in, it can touch the grinding wheel gently, and conduct a small amount of edge grinding first, observe the uniformity of sparks, adjust the pressure on the hand in time, and pay attention to the cooling of the bit, so as not to make it wear too much fire, causing the edge to change color, and then anneal it to the edge. When the temperature of the edge is high, the drill bit shall be cooled in time.

the edge of the drill bit shall be swinging up and down, and the tail of the bit shall not be warped

This is a standard bit grinding action. The main cutting edge should swing up and down on the grinding wheel, that is, the hand holding the front of the bit should swing the bit up and down evenly on the grinding wheel surface. The hand at the grip can not swing, and the back handle should not be warped upward, that is, the tail of the drill bit cannot be higher than the horizontal center line of the grinding wheel, otherwise the edge will be blunt and cannot be cut. This is the most critical step, the bit is well and bad, and it has a great relationship. When grinding is similar, start with the edge, and gently rub the back corner to make the back of the blade more smooth.

ensure that the blade tip is opposite to the axis, and the two sides are symmetrically and slowly repaired

After one edge is well polished, then the other edge must be worn. It is necessary to ensure that the edge is in the middle of the drill axis and the edges on both sides should be symmetrical. Experienced masters will look at the symmetry of the drill point in the light and slowly repair and grind. The back angle of the cutting edge of the drill bit is generally 10 °~ fourteen °, The back angle is large, the cutting edge is too thin, and the vibration is strong during drilling. The hole is in the shape of three or five sides, and the chip is needle shaped; The back angle is small, the axial force is very large during drilling, it is not easy to cut in, the cutting force increases, the temperature rises greatly, the bit is hot, and even cannot be drilled. The back angle grinding is suitable. The front point is centered and the two edges are symmetrical. When drilling, the bits are light and fast in chip discharge, without vibration and the hole diameter will not expand.

The Must-know Manual Sharpening Technique of Twist Drill 3

after grinding the two edges, pay attention to the bit tip of the bit with larger diameter

After the two edges of the drill bit are well ground, there will be a plane at the tip of the two edges, which will affect the center positioning of the bit. It is necessary to reverse the angle behind the edge to grind the plane of the tip as small as possible. The method is to erect the drill bit, align with the angle of the grinding wheel, and pour a small groove towards the edge tip at the root behind the edge. This is also an important point for the bit to be centered and cut lightly. Note that when grinding the chamfer of the edge tip, it is not allowed to grind on the main cutting edge, which will make the front angle of the main cutting edge larger and directly affect the drilling.

Of course, there is no certain setting of grinding bit, and experience needs to be accumulated in practical operation. Through comparison, observation and repeated test, it is sure to grind the bit better.

Tr? l?i

Email c?a b?n s? kh?ng ???c hi?n th? c?ng khai. Các tr??ng b?t bu?c ???c ?ánh d?u *

精品国产Av无码久久久一区二区| 日本高清一区二区三区水蜜桃| 大男人在线无码直播| 少妇无套带白浆嗯呢啊污| 裸体美女被操的啊啊直叫| 亚洲综合青青草原在线| 黄色软件大屌怒戳粉嫩小穴| 欧美亚洲熟妇视频在线观看| 亚洲日韩不卡一区二区三区| 快速了解国产一级a爱片| 高清最新操逼吃鸡巴视频| 一级做a爱过程免费视频俩| 久久国产精品二卡| 精品少妇一区二区三区中文字幕| 91久久高清国语自产拍| 久久亚洲精品无码AV宋| 骚片视频在线观看| 国产精品国产精黄 | 人妻人久久精品中文字幕| 日韩av大片一区二区三区| 亚洲欧洲精品无码久久久| 男生狂操女生污视频| 大鸡巴抽插小穴色虐视频| 国产熟女视频一区二区三区| 美女麻豆颜色光屁股眼子| 欧美日韩一区二区成人在线| 日韩一区二区三区夜色视频| 日本不卡免费一区二区视频| 国产高清在线观看一区二区三区| 18岁以下禁看美女的胸| 伊人久久久久久久久香港| 黄色软件大屌怒戳粉嫩小穴| 精品久久久久亚洲中文字幕| 日韩在线视频不卡一区二区三区| 那种视频在线观看你懂的| 久久综合色伊人九色91| 新视觉亚洲三区二区一区理伦| 鸡巴插进缝里 日本| 97国产精品免费一二区| 骚穴手机在线视频| 久久综合色伊人九色91|