Concrete Leadwood Screw Anchor

Purchase Concrete Leadwood Screw Anchors

Technical Information:

The cavity of the Leadwood screw anchor tapers and is designed to facilitate proper expansion in masonry. The anchor is split from the bottom up for most of its length and has longitudinal ribs for a portion of its length. The top end of the anchor tapers outward from the anchor diameter into a tubular thin section cone. The tapered diameter at the outer end of the anchor, in combination with the longitudinal split, facilitates ease of initial expansion and prevents the anchor from turning in the masonry. As the screw progresses deeper into the anchor, the longitudinal ribs bite into the masonry, preventing the anchor from twisting and allowing the screw to form its own threads.

Leadwood Screw Anchor concrete anchor/fastener - Approvals:

Meets G.S.A. Specification FF-S-325, Group IV, Type 1.

Leadwood Screw Anchor concrete anchor/fastener - Applications:

Light-duty into concrete, brick and block

Leadwood Screw Anchor concrete anchor/fastener - Installation:

  1. Drill a hole in the base material (see chart below for recommended hole size) using a hammer drill and a carbide-tipped masonry bit to a depth equal to the anchor length, plus one-quarter inch (1/4") or more.
  2. Clear the hole of all debris.
  3. Place the leadwood screw anchor into the hole and, with light hammer blows, tap the anchor until it is flush with the surface of the base material.
  4. Insert the sheet metal screw through the fixture and into the anchor and tighten.

Leadwood Screw Anchor concrete anchor/fastener - Screw Length:

The length of the sheet metal screw required is equal to the thickness of the material to be fastened, plus the anchor length, plus 1/4" (for complete expansion of anchor). 

Leadwood Screw Anchor concrete anchor/fastener - Anchor Spacing:

The forces on a Leadwood screw anchor are transferred to the material in which it is installed. If the anchors are installed too close together, it can cause an interaction of the forces, thus reducing the holding power of the anchors. As a rule of thumb, the concrete anchor industry has established a minimum standard of ten (10) anchor diameters for spacing between anchors and five (5) anchor diameters from an unsupported edge. When vibration or sudden impact are part of the load condition, anchor spacing should be increased.

Leadwood Screw Anchor concrete anchor/fastener - Technical Data

Anchor Size Hole Size Screw Size Pull-Out 3000 psi concrete
6-8 x 3/4" 1/4" 1/8" - 3/16" 286 lb.
6-8 x 1" 1/4" 1/8" - 3/16" 352 lb.
6-8 x 1-1/2" 1/4" 1/8" - 3/16" 440 lb.
10-14 x 3/4" 5/16” 3/16” – 1/4" 792 lb.
10-14 x 1" 5/16" 3/16" - 1/4" 792 lb.
10-14 x 1-1/2" 5/16" 3/16" - 1/4" 990 lb.
16-18 x 1" 3/8" 5/16" 1254 lb.
16-18 x 1-1/2 3/8" 5/16" 1254 lb.

Values shown are average ultimate values and are offered only as a guide and are not guaranteed. A safety factor of 4:1 or 25% is generally accepted as a safe working load. Reference should be made to applicable codes for the specific working ratio.