Drill Parameter Study.
Abstract
The purpose of this study was to evaluate methods of monitoring the hole drilling process and determining when the drill becomes dull and inadequate for producing high quality holes in multilayer circuit boards (MLBs). A literature search/vendor survey provided sufficient information to conclude that the detection of heat generated by the drilling process would be the best means of accomplishing this task. Two types of infrared sensing devices were used to monitor the temperature increase of the drills during the hole drilling operation and the results were correlated with microsections of the holes. Various drill geometries and surface finishes were evaluated and a significant difference in performance was obtained using the newer micro-grade type drills. The scanning electron microscope was used in the evaluation of the drilled hole microsections and in the examination of the cutting surfaces of the carbide drills before and after drilling. In the last phase of the study, four various sized drills were monitored at drill speeds of 50,000 and 80,000 RPM using the IR sensing device. Every 500th hole was cross-sectioned, stained and examined for evidence of smear.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1979
- Accession Number
- ADA065541
Entities
People
- Jack Quintana
- Tom Weismuller
Organizations
- Hughes Aircraft Company