Machine Screw Anchor FAQ

What is a machine screw anchor?

Purchase Machine Screw Anchors

Machine screw anchors are setting tools used to expand the anchor in the base of the material. Once the anchor is installed, a bolt can be threaded and unthreaded as needed.

When should I use one?

These anchors work for light to medium duty fastening and can be installed in concrete, brick, block, and mortar joints.

What materials are used to make one?

It has two parts: the sleeve and the internally threaded cone. Both parts of the completed unit are made from a rust-proof material called Zamac.

Are they available in stainless steel?

No, they are only available in a Zamac, which is a rust resistant material.

What sizes are available?

These anchors are available in six sizes: 1/4”, 5/16”, 3/8”, 1/2”, 5/8”, and 3/4”.

Are caulk-in anchors and machine screw anchors the same type of anchor?

Yes, they are the same type of anchor. Caulk-in Anchor is a brand name and machine screw anchor is the generic term that describes the anchor.

What’s the difference between a machine screw anchor and a drop-in anchor?

There are a number of differences between the two. The main difference is that the drop-in anchor can only be used in solid concrete while the machine screw anchor can be used in a variety of base materials.

Why don’t these anchors come with bolts?

They do not come with bolts because every application needs a specific length, type, and head style of bolt.

How do I know what size bolt to put into the anchor?

The designated diameter of the anchor is equal to the diameter of the bolt that it can be threaded into. For example, a 1/2” anchor requires a 1/2” bolt.

What base materials work with this anchor?

The anchor can be used in a variety of masonry base materials including concrete, brick, block, and mortar joints.

How do I install a machine screw anchor?

Installation is easy. Drill the hole, clean the hole, install the anchor, and finish it with a setting tool. For more detailed instructions, please visit our Tips & Tricks page.

How far apart must I install screw anchors from each other?

Installing the anchors too close together can cause an interaction of the expansion forces, thus reducing the holding power of the anchor. As a rule of thumb, the expansion industry has established a minimum standard of ten anchor diameters for spacing between anchors .

Do I have to use a setting tool?

Yes, a setting tool is required. It must be the correct size setting tool for the anchor being installed to ensure that the anchor is set properly.

Can I set this anchor below the surface of a base material?

Yes, these anchors can be set below the surface of base materials as long as the setting tool can still reach the anchor to set it properly.

Can I remove the screw anchor from the base material once it is set?

No. Once set into the base material, the anchor cannot be removed without damaging the base material.

Can I remove the bolt from the anchor without removing the anchor from the concrete?

Yes. Once the anchor is set in the base material it stays set. The bolt can be removed and reinserted without affecting the holding values of the anchor.