dartsrules

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SECTION 2: DIRECTORY OF GENERAL INFORMATION

TECHNICAL INFORMATION FOR DARTSâ SELF-DRILLING SCREWS

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SELF-DRILLING SCREW SELECTION GUIDE
\| SELF-DRILLING SCREW SELECTION GUIDE \| RECOMMENDATIONS FOR DRILL CAPACITY \|

Drill Flute The length of the drill flute determines the metal thickness that can be drilled. The flute itself provides a channel for chip removal during drilling action. If it becomes completely imbedded in material, drill chips will be trapped in the flute and cutting action will cease. This will cause the point to burn up or break. Point Length The unthreaded section from the point to the first thread should be long enough to assure the drilling action is complete before the first thread engages the drilled metal. Screw threads advance at a rate of up to ten times faster than the drill flute can remove metal. All drilling therefore should be complete before threads begin to form. Drilling Through Wood To Metal If your application calls for drilling through wood over 1/2" in thickness, a clearance hole is required. Select a fastener with break away wings for this type of job. The wings will ream a clearance hole and break-off when in contact with metal surface (minimum metal thickness .090") to be drilled.

RECOMMENDATIONS FOR DRILLING CAPACITY

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