Keyword: PCB drilling holes, PCB
PCB drilling holes in the hole size is not allowed, how to deal with distortion, firstly analysis the reasons of the problem: drilling tsui specification error; Feed speed or speed is not appropriate; Drill tip excessive wear; Amounts of drill tip resharpening and crumbs slot length back bottom below the prescribed standards; Excessive deflection axis itself; Drill tip tip, borehole diameter larger; Wrong size; When change drilling tsui not bore; Drill tsui alignment error; In drill tip position when inserted wrong; Not check the aperture figure; Spindle put down the knife, resulting in pressure knife; Mistyped the serial number of parameters.
Then suit the remedy to the case and find out the solution:
(1) before the operation should be check bit size error and control system instructions.
(2) to adjust the feed rate and rotational speed to the ideal state.
(3) replacement drilling tsui, and limit the number of each drill tsui drilling. Usually according to the double panel (per stack four) to 3000 ~ 3500 holes; High density multilayer can drill 500 holes; For FR - 4 (every fold three block) to 3000 holes; For a hard FR - 5, the average 30% reduction.
(4) limit the number of drills resharpening and resharpening size changes. 500 per drill for drilling sandwich plate hole grinding time, allow grinding 2 ~ 3 times; Once every 1000 holes can be grinding; For double panel 3000 per drill holes, grinding time, and then 2500 holes; Sharpening again 2000 holes. Bit timely resharpening, can increase the number of drills resharpening and increase the bit life. Through measuring tool microscope, wear depth within the two main cutting blade length should be less than 0.2 mm. When heavy grinding mill to 0.25 mm. The shank drill can resharpening 3 times; Spade bit resharpening twice.
(5) feedback to maintenance operation process of dynamic deflection tester checks the main shaft deflection, serious when by professional supplier for repair.
(6) with 20 times mirror inspection before drilling cutters, bad will drill tip sharpening or scrap processing.
(7) check, measure for many times.
(8) in replacing drill tip can be measured in drilling tsui, has been replaced by measuring drill tsui drilling the first hole.
(9) is arranged to count when drilling tsui tool storage location.
(10) replacing drilling tsui see serial number.
(11) in the case of a knife to one by one check figure the actual aperture of the aperture.
(12) cleaning nozzle, pressure measurement and check carefully after knife surface.
(13) in the input tool serial number to check again and again.
Source: //www.seekic.com
