Let Gun Drills suppliers tell you How to calculate the Gun Drills length as below:

1.The nominal cutting blade diameter can be subdivided to 0.001mm according to customer needs

2. Please mark the order according to the following standard

D(Drill Bit Diameter)xL(Overall Length)- Driver Number

L(Overall Length)

D=drill bit diameter

W=drilling depth

LB=width of supporting guide casket

L1(Useful Length)

H=driver number

LA=drill tip length

L1(useful length)

L2=minimum for chips discharge allow

overall length calculated as follows:

overall length=LA(drill tip length)+W(drilling depth)+LB(width of supporting guide casket)+ L2 (minimum for chips discharge allow)+ H(driver length)

3. Please highlight the workpiece material, hardness, hole tolerance, and hole roughness

4.Mark the driver code number

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