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Field Guide

Covering · Seat the washer, don’t spin the tip off

Screw installation

Electric screw gun, 0–2000 RPM, depth nosepiece. No impact drivers. Three threads past the substrate. Swarf off the panel or it rusts.

screw
SDS
RPM
overdrive
washer
swarf

Proper installation is structural and weathertight. The erector furnishes the guns, the bits, and the technique. Bad seating leaks, snaps heads, or burns drill tips.

The gun

  • Minimum 6 amp.
  • Variable speed, 0–2000 RPM no-load. Do not use high-speed guns over 2500 RPM.
  • Depth-sensing nosepiece or adjustable clutch.
  • Correct magnetic bits. Replace worn bits — they wreck heads.
  • Keep steel filings out of the magnetic socket so the head seats.

Do not overdrive

Screws with sealing washers must seat the washer for weathertightness. ALL drill filings come off the steel or they rust. Screws without washers seat snug, head flush with the steel. Excess torque snaps heads. Screw length must penetrate all connected material — at least three threads past the substrate.

Underdriven, correctly driven, overdriven — with and without a sealing washer.

Drill-point speed

Avoid tip burnout. Set RPM for the point type. Apply steady, uniform pressure.

Maximum RPM by drill point

PointMax RPMTotal thickness
Dp-120000.018″ – 0.095″
Dp-2 & 318000.036″ – 0.175″
Dp-418000.125″ – 0.250″
Dp-4.518000.125″ – 0.375″
Dp-518000.125″ – 0.500″
Self-tapping1000Pilot hole required

Screw gun RPM

Variable speed 0–2000. Depth nosepiece. No impact. ≥ 6 amp.

Maximum RPM

2,000 RPM

Total thickness 0.018″ – 0.095″. Steady pressure. Three threads past the substrate. Swarf off the panel.

Screw bolts

Install with a ½″ electric impact wrench, 5″ extension, and magnetic sockets. Screw bolts are not self-drilling — they need a pilot hole. With a sealing washer, do not overtighten. Without a washer, seat flush, do not overdrive.

Improperly installed screws come out and get replaced.