Cotton Cobs

Cotton cobs are a traditional and reliable fibre used for sealing threaded pipe joints. Commonly applied alongside jointing compounds such as Boss White, they help create a tight, secure seal on male threads. Available in 250g and 1kg, cotton cobs are suitable for plumbing, heating, and mechanical pipework installations.

 
Key Features

• Natural cotton fibre for thread sealing 
• Used with jointing compound for leak-free joints
• Ideal for threaded pipe fittings
• Available in 250g and 1kg

 
In-Depth Description

Cotton cobs are widely used by plumbers and installers as a proven method for sealing threaded pipe fittings. When wrapped around the male thread and combined with a suitable jointing compound, the cotton fibres fill gaps and imperfections between threads, helping to form a strong, reliable, and leak-free seal once the joint is tightened.

 
The natural cotton material is easy to handle and wraps smoothly around threads, allowing the installer to control the amount applied for each joint. When used with compounds such as Boss White, the cotton fibres absorb the paste, improving lubrication during assembly while ensuring the fibres compress evenly within the joint. This results in a tight, durable seal that remains stable under normal operating pressures and temperatures.

 
Cotton cobs are suitable for a wide range of plumbing, heating, and mechanical applications, including water pipework and general threaded connections. They are particularly valued in traditional installations and maintenance work where a dependable, adjustable jointing method is preferred. The joint can be aligned correctly during installation without compromising the seal.

 
Available in small 250g for light or occasional use and larger 1kg for regular or high-volume installations, cotton cobs offer flexibility to suit different project requirements. Simple, effective, and time-tested, they remain an essential consumable for achieving secure threaded pipe joints.

We offer nationwide next working day delivery on stocked products for orders placed before 12:00 pm, subject to stock availability.

Delivery charges are calculated based on your order's size, weight and destination and will be shown at checkout where applicable.

Some oversized, bespoke or non-stock items may require additional lead time. If this affects your order, we'll let you know as soon as possible.

Collection is available from our warehouses in Rochdale, Halesowen and East Kilbride, subject to stock availability. Please check the individual product listing for collection availability.