Silicone Caps

Our Silicone Caps are manufactured from a 40-80sh grade of Silicone, with varying shore hardnesses of 35-85 capable of resisting temperatures between -40 to +350°C.

Yes, our Silicone Caps produced in line with ISO9001:2000 Manufacturing standards to give you confidence in the quality of product that we supply.

Yes we are able to provide a Data Sheet for each and every size available through our website. You can request one by getting in touch with us using our contact form, or by speaking over Live Chat.

Silicone caps are high-temperature resistant protective covers made from premium silicone rubber. They're primarily used for masking applications during powder coating, anodising, shot blasting, e-coating, plating, and painting processes. These caps protect threaded and non-threaded studs, bolts, tube ends, and holes from coating overspray while withstanding extreme temperatures up to 350°C.

Our high-temperature silicone caps are used across a variety of sectors, including:

• Powder coating and metal finishing

• Automotive manufacturing and maintenance

• Aerospace and defence

• Electronics and electrical assembly

• General engineering and fabrication

• Silicone caps are chosen where heat resistance, flexibility, and a secure fit are essential.

Our high-temperature silicone caps can withstand temperatures between -40°C and 350°C (depending on the type chosen). This makes them ideal for powder coating ovens, anodising processes, and other high-temperature applications where standard materials would melt or degrade.

We stock a wide range of silicone caps to suit different applications, including:

• Standard round silicone caps in a variety of internal diameters and lengths

• High-temperature masking caps for use during finishing

• Tapered and cone-shaped caps for a snug fit on irregular shapes

• Flat and flanged end caps for specialised protection

Our range covers popular metric sizes and bulk pack options for commercial use.

Silicone caps are ideal for use as masking products during powder coating, electroplating, and painting processes:

• They protect threads, studs, and fittings from unwanted coating or contamination

• The flexible, heat-resistant material allows repeated use through multiple cycles

• Easy push-fit design makes installation and removal quick and efficient

• Prevents costly rework by ensuring clean, coated-free threads and holes

To select the correct silicone cap for your needs:

• Measure the outside diameter of the part to be capped

• Choose a cap with an internal diameter slightly smaller than the component for a secure fit

• Consider the application temperature and chemical exposure

• Select the cap length and shape (standard, tapered, flat, or flanged) based on your protection requirements

If you need assistance selecting the right size or would like to discuss custom options, contact our expert team on 01233 713581.

Yes, silicone caps are designed to be reusable multiple times. The premium silicone material maintains its flexibility and doesn't harden, crack, or become brittle after exposure to high temperatures. Simply remove any coating residue by flexing the cap, and it's ready for reuse.

When selecting a silicone cap, the inside diameter (ID) should be 2-5% smaller than the diameter of the stud or bolt you're masking. For optimal fit, choose a cap length that's slightly longer than the masking area. If the cap ID is less than 5% of the stud diameter, ensure you select a longer cap for easier removal.

Silicone caps offer superior temperature resistance (often beyond 350°C) compared to vinyl caps (up to 170°C). While vinyl caps are more economical, silicone caps provide better flexibility, chemical resistance, and durability for demanding applications like powder coating and anodising.

Silicone cone caps feature a tapered design that allows them to fit over a range of diameters, making them more versatile than standard caps. They're ideal when you have varying stud or hole sizes during the masking process. The conical shape provides flexibility for masking threaded studs, rods, bolts, or tube ends where exact sizing isn't critical.

Yes, silicone cone caps are dual-purpose. Their tapered design allows them to function as caps over external features like studs and bolts, or as plugs when inverted to seal holes. This versatility makes them an efficient choice for busy production lines where multiple masking solutions are needed.

Silicone washer caps feature an integrated washer or flange at the base that creates a grounding area around the masked stud or hole. This eliminates the need for two-stage masking and provides both masking and grounding protection in one product, making them particularly useful for powder coating applications.

Yes, silicone washer caps are designed to work on both threaded and non-threaded studs and holes. The flexible silicone material conforms to irregular shapes and provides an effective seal regardless of the surface finish.

Silicone rectangular covers are specifically designed for masking rectangular and square-shaped components such as bus bar terminals, grounding tabs, and electrical enclosures. Their rectangular shape provides better coverage and fit compared to round caps on square or rectangular features.

Eze caps (Easy Pull Tab caps) feature an ergonomic finger pull-tab or extended tab design that makes removal quick and effortless. This eliminates the need for tools during removal, reducing the risk of damage to threads or part surfaces while speeding up the masking process.

Pull-tab caps offer several advantages: faster removal without tools, reduced risk of damaging delicate surfaces or threads, improved efficiency in production environments, and easier handling when wearing gloves. They're particularly valuable in high-volume coating operations.

For tube end applications, create a small slit in the top of the cap to allow air pressure to escape, preventing blow-off during the coating process. Ensure proper sizing (cap ID should be 2-5% smaller than the part diameter) for a secure fit.

Absolutely. Silicone caps are commonly used in shot blasting operations to protect threaded holes, studs, and sensitive surfaces from abrasive media. Their flexibility and durability make them ideal for withstanding the mechanical forces involved in blasting processes.

Simply flex and squeeze the silicone cap after use. The flexibility of the material causes any dried coating to crack and flake off, returning the cap to near-new condition. Avoid using sharp tools or pliers, as silicone has low tear resistance.

Inside Diameter (ID) is the internal measurement of the cap opening - this should be 2-5% smaller than your stud/bolt diameter for proper fit. Outside Diameter (OD) is the external measurement of the cap. When using caps as plugs, the OD should be at least 7% larger than the hole diameter.

Select a cap length that's slightly longer than the area you need to mask. This ensures complete coverage and makes removal easier. If the cap ID is very close to the stud diameter (less than 5% difference), choose a longer cap to provide adequate grip for removal.

Store silicone caps in a cool, dry place away from direct sunlight and ozone sources. Avoid contact with oils, solvents, or sharp objects. Proper storage helps maintain the material's flexibility and extends service life.

With proper care and within temperature limits, quality silicone caps can be reused dozens of times. The exact number depends on the application severity, temperature exposure, and handling care. Replace caps when they show signs of cracking, hardening, or permanent deformation.

When stored properly, silicone caps have an excellent shelf life of several years. Silicone doesn't degrade significantly over time when stored correctly, making it economical to stock various sizes for different applications.

Need your parts tomorrow? Our rapid same day dispatch has got you covered! Simply place your order before 4pm Mon-Thurs or 2pm Friday and select our Next Day Delivery service in the shopping cart. We also offer Guaranteed AM delivery when required, in addition to a Saturday delivery option.

If you don't mind waiting, we have a Free delivery method for orders over £30, and an economic £4.85 2nd Class delivery for orders between £20-£30.

Free Samples can be requested through our product pages, displayed in the sizing table beside the product you require. Please note you can always give us a call on 01233 713 581 or contact us on Live Chat to discuss samples.

You do not need to sign up to place an order, but it is recommended if you'd like to gain loyalty points, giving discount off future orders. To learn more about loyalty points, please view our rewards scheme page.

If you're unsure which part you need then please do not hesitate to give one of our friendly Sales Team a call on 01233 713 581 and they can assist you. Alternatively, we're active on Live Chat during office hours. You can open this using the button in the bottom right corner of the website. Alternatively, you can write to us using our contact form.

We offer a return period on all of our products to give you peace of mind, to view our policies and learn more about this process should it be required, please see our returns policy page.

In most cases we have the facilities to offer you different colours of a product, specific to your requirements. Minimum order quantities may apply depending on the manufacturing technique in question, but please get in touch with any queries you may have.

Please note that there is a minimum order value of £10 through our website (inclusive of VAT).
If you're new to our website you may want to check out our frequently asked questions section for answers to common customer queries.

While browsing the website you may come across abbreviations used for material names that you are unfamiliar with. You can find an explanation for these in our material abbreviations guide.