Bremick BSW Socket Head Cap Screw, 1/2", 1 1/4"

A socket head cap screw has a cylindrical head with a socket drive, so it is turned with a key or bit instead of a spanner. There are 45 Bremick BSW socket head cap screw items (BSW thread, alloy steel, plain finish): sizes 3/16" to 3/4", lengths 3/8" to 5-1/2".

BSW is British Thread Standard Whitworth and TPI as threads per inch. Threads per inch are shown for each size. Check the key size against a screw in hand. Items shown as Each are single pieces; the others are supplied in the pack or box quantity shown in the table.

Where this product is used

• Machine building and tooling, where a high-strength cap screw sits recessed in a counterbored hole
• Clamping plates, covers and housings down onto tapped holes
• Compact assemblies where a spanner will not fit but a hex key will
• Workshop jobs where the part is protected by its surroundings
• There are 45 items with diameters from 3/16" to 3/4" and lengths from 3/8" to 5-1/2", so work out the size you need first and then read across the table

Features

• 45 items: 3/16" to 3/4"
• BSW thread, socket head cap screw
• Alloy steel, plain finish
• Pack quantity shown for each item
• Plain (uncoated) steel for dry indoor and machinery use
• Material: alloy steel

Key specifications

Choosing the finish

A plain finish means bare steel with only a light oil film on it. It will rust quickly in damp conditions.

Keep plain parts for dry indoor use, machinery and assemblies that get painted, oiled or enclosed. Outdoors or in damp areas, a hot dip galvanised or 316 stainless alternative is the better choice.

Plain alloy steel socket screws are the normal choice for tooling and machine building, where the parts are usually oiled or enclosed.

Thread and strength

The thread is BSW (British Standard Whitworth), a 55° imperial form seen on older British-origin machinery, so the nut or tapped hole must also be BSW.

Fasteners are not lifting rated unless marked.

Choosing the right option

Choose the thread form first: the screw must match its nut or tapped hole in thread form, diameter and pitch. Sizes are nominal diameters in inches; compare the threads per inch with your thread. By convention the length of a socket head cap or button head screw is measured from under the head. Check the key size against a screw in hand.

See also: Bremick Metric Socket Set (Grub) Screw, Alloy Steel, Plain, M3 to M20, Bremick BSW Nylon Insert Lock Nut, Zinc, 1/2", Pack of 200, Bremick BSW Hex Nut, Grade 2, Mild Steel, Plain, 3/4" and 7/8".