Processing Technique 1: Usage of Marking and Punching Machine
Dashing
When manually performing drilling operations, it is necessary to determine the hole position and draw the center of the hole in a cross shape (X, Y direction) on the workpiece. When high-precision marking operations are required, the workpiece will be fixed on the platform and a marking frame or altimeter will be used. In addition, accuracy may decrease, but sometimes a marking needle and ruler (ruler) are used.
punch
If a cross is drawn during the marking operation to indicate the center of the hole for drilling, the intersection point between the top of the drill bit and the cross will be misaligned. The reason is that the drill bit has the characteristic of being detached from the target position due to rotation. To prevent this detachment, a punch can be used to create a dent at the intersection of the cross to prevent detachment. But punching also requires skills. Due to the small grooves on the cross line, this groove is used as a guide to slide the top of the punch and align it with the intersection point. The trick at this point is to use the lines drawn later.
Processing technique 2: Process larger holes in stages
Even with the use of a punch press, it is not possible to cleverly locate the center of a large diameter drill bit. This is because the top of the large-diameter drill bit has a flat part called the cross edge, which cannot be positioned because it is larger than the punching hole. In this case, first use a small diameter drill bit to drill a shallow pre hole, so that the top of the large diameter drill bit can enter and be correctly positioned.
Handling technique 3: Reduce damage rate
Based on my experience, I feel that there are more injuries when working on a drilling machine. When the drill bit penetrates, the workpiece is driven by the drill bit to rotate violently, which can damage the hand holding the workpiece.
Avoidance measures ①
By placing a scrap board under the workpiece during processing, it is possible to prevent the drill bit from biting through.
Avoidance measures ②
If possible, please use clips or other tools to secure the workpiece. But it needs to be tightened after aligning with the punching position.
Avoidance measures ③
Properly control the speed of the drill bit. The product catalog of tool manufacturers lists suitable rotational speeds and feed rates based on the diameter of the drill bit and the material of the workpiece. Therefore, these data are referenced for machining to prevent workpiece rotation and improve machining accuracy.
Avoidance measures ④
By using cutting oil, the resistance during machining can be reduced and the rotational force transmitted to the workpiece can be reduced.
