Working conditions
Identify temperature, contact fluids and repeated movement.

Custom manufacturing example · Custom silicone rubber stopper/flexible rubber caps for hole
CUSTOM RUBBER & SILICONE MANUFACTURING
A custom component for your assembly.
Define the mating surfaces, dimensions and working conditions. ETOL manufactures the part to the agreed design and material.
Share the part, its application and your estimated quantity.

Selected for the contact, temperature and movement
Define the visible surfaces and intended color
Develop holes, lips and walls around the mating parts
Match the attachment and installation method
Custom flexible rubber caps cover a defined profile with a compliant molded wall. Silicone versions can be dimensioned around the opening, depth, and surrounding clearance. Flexibility helps during fitting, but the cap still needs an internal shape suited to the component it covers.
Consider the entrance and the final seated region separately. A cap may pass the first edge easily and then stop on a wider shoulder farther inside. Stretching the mouth harder can conceal that mismatch without creating the intended contact. Establish the full covered profile and leave a suitable surface for controlled fitting and removal.
Select the formulation and hardness for the actual medium, temperature, and handling frequency. Keep the inside clean before installation and check that the wall has not folded near the rim. For a plug style, define the inserted body separately from the cap cavity. After removal, inspect thin transitions for damage and preserve the complete custom geometry when replacing the part so flexibility is used within the designed fit rather than to overcome an unsuitable opening.
Photos illustrate structure or material appearance only. Silicone versions can be dimensioned around the opening, depth, and surrounding clearance. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.
FIND THE RIGHT FIT
Compare inside diameter A with the outside of the part being covered. Check inside depth C and overall dimensions B and D for available clearance. These RSE references show a round cap with one closed end.
43 closed-end cap sizes. A is the inside diameter and C is the usable internal depth; B and D describe the outside envelope.
| P/N | A | B | C | D | Color | Unit |
|---|---|---|---|---|---|---|
| RSE3.7-7-9 | 3.7 | 7 | 9 | 11 | black,white | mm |
| RSE4.7-8-9 | 4.7 | 8 | 9 | 11 | black,white | mm |
| RSE5.7-9-10 | 5.7 | 9 | 10 | 12 | black,white | mm |
| RSE6.7-10-10 | 6.7 | 10 | 10 | 12 | black,white | mm |
| RSE7.7-11-11 | 7.7 | 11 | 11 | 13 | black,white | mm |
| RSE8.7-12-12 | 8.7 | 12 | 12 | 14 | black,white | mm |
| RSE9.7-14-13 | 9.7 | 14 | 13 | 15 | black,white | mm |
| RSE10.7-15-14 | 10.7 | 15 | 14 | 16 | black,white | mm |
| RSE11.7-16-15 | 11.7 | 16 | 15 | 17 | black,white | mm |
| RSE12.7-17-15 | 12.7 | 17 | 15 | 18 | black,white | mm |
| RSE13.7-18-15 | 13.7 | 18 | 15 | 18 | black,white | mm |
| RSE14.7-19-15 | 14.7 | 19 | 15 | 18 | black,white | mm |
| RSE15.7-20-16 | 15.7 | 20 | 16 | 19 | black,white | mm |
| RSE16.7-21-16 | 16.7 | 21 | 16 | 19 | black,white | mm |
| RSE17.7-22-16 | 17.7 | 22 | 16 | 19 | black,white | mm |
Need a different fit? Share the opening dimensions, mating profile and intended use for a custom size.
Identify key dimensions, mating surfaces and quantity
Agree the compound and manufacturing approach
Review the fit and agreed requirements in the assembly
Manufacture and check against the approved requirements
Identify temperature, contact fluids and repeated movement.
Consider hardness together with wall thickness and support.
Check access, mating dimensions and the fitting sequence.
Yes. Show the receiving opening, contact surfaces and clearance limits. We can review the dimensions and retaining features around the intended fit.
Agree the critical dimensions, material, hardness, visible surfaces and sample requirements. Explain how the part is installed and which interfaces control its function.
A sample can help explain the structure. Compare it with the assembly because wear, swelling or compression may have changed its original dimensions.
The material, part geometry, tooling, quantity and finishing affect the quotation. Include the intended batch size and delivery destination when describing your requirements.
DISCUSS THIS COMPONENT
Share the fit, operating conditions and quantity with our manufacturing team.