Unthreaded Round Spacers are selected when an assembly calls for setting a fixed distance on a screw that passes straight through it, with no thread of its own. This application guide to the Trade series (plain bore spacer) type covers concrete end-uses, the specification checklist, correct installation, and where an alternative fastener performs better. Stocked across roughly 3.2 mm to 6.4 mm, they cover general to heavy-duty work.
Typical Applications for Unthreaded Round Spacers
The most common settings where these are specified:
- Fabrication & metalwork: bench and on-site assembly of steel frames, enclosures and weldments.
- Electronics assembly: holding boards off a chassis and stacking multiple boards at a fixed pitch.
- Enclosures & panels: spacing a fascia, guard or label plate off the surface behind it.
- Machine alignment: setting and correcting the height of a component on its mounting.
- General machine building: fastening covers, brackets, motors and sub-assemblies on production equipment.
How to Specify Unthreaded Round Spacers for Your Application
- Size: Select on bore diameter, and confirm it against the mating feature in the assembly. This product spans 3.2 mm–6.4 mm; check the full table below for the exact dimensions of each size.
- Material: Choose the material and finish for the service environment — plated steel for general use, stainless for corrosion resistance.
- Environment: For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient.
- Standard: This product is supplied to Trade series (plain bore spacer). Quoting the standard on your order guarantees interchangeable dimensions between suppliers.
Where Unthreaded Round Spacers Are Not the Right Choice
Match the fastener to the load, environment and whether the joint must be reopened; the wrong class or style is the usual cause of joint failure.
