R&R WTC motor shaft Seal... Help needed

[Timothy L]

What are the O-rings in R&R cylinders usually made of and what lubricant is normally used with them. Thank you.

[Subculture]

They're silicone rubber seals. If it has bellows they will likely be nitrile, but any o-rings used will be silicone. Silicone o-rings tend to be a little softer than most nitrile o-rings, I think that's the main reason Ron uses that compound, but he would be the best person to ask.

[Timothy L]

Thank you.

[Subculture]

If you use a good quality PTFE grease, that will work with all the rubber compounds we use in model submarines.

e.g. https://www.polymax.co.uk/o-rings/si...se/ptfe-grease

[Wax Savage]

What are the O-rings in R&R cylinders usually made of and what lubricant is normally used with them. Thank you.

Hi Timothy,

Here is the lowdown on the red O-rings used in R&R WTC's. They are called VMQ (Silicone) O-rings.

In the world of O-rings and industrial seals, VMQ is the standard industry abbreviation for Vinyl Methyl Silicone rubber. It is the most widely used material in the silicone family, highly prized for its incredible resistance to extreme temperatures and excellent flexibility
Key Characteristics of VMQ O-Rings

• Extreme Temperature Range: VMQ performs reliably in temperatures ranging from -60°C to 200°C (and up to 250°C for short periods).
• Weather & UV Resistance: Highly resistant to sunlight, ozone, and general atmospheric aging.
• Safety & Hygiene: Physiologically neutral, odorless, and tasteless. Many compounds meet FDA/NSF requirements for food and medical applications.

For VMQ (Silicone) O-rings, the golden rule is to never use silicone-based grease or oil. Applying silicone lubricant to a silicone O-ring causes the material to over-swell, degrade, and fail prematurely.

Use the following compatible lubricants:

• Fluorosilicone or PTFE (Teflon) Based Greases: These are the best choice for VMQ O-rings. They offer excellent lubrication without causing the silicone to swell or degrade.
• Glycerin or Vegetable-Based Lubricants: Safe for static (stationary) seals and excellent for applications requiring food-safe or environmentally friendly materials.
• Soap and Water: Can be used as a temporary lubricant for installation if no specialized grease is on hand, though it is not a long-term lubricant. [1]

What to Strictly Avoid

• Silicone Grease/Oil: Will degrade VMQ material over time.
• Petroleum-Based Products (Vaseline, WD-40, motor oil): Will chemically break down, swell, or dissolve silicone rubber
• How to Apply;

1. Clean the housing groove and the O-ring to remove dirt or debris.
2. Apply a thin, uniform film of your chosen lubricant to the O-ring. Excess grease can attract contaminants or compromise the seal.

[Timothy L]

Wow - thank you for the helpful recap!!