Can anyone give me any idea how to fit a new rubber speedo mounting ring into the divers helmet on my BSA B31?

Question

I have tried to fit the new rubber ring to the helmet and then fit the speedo but as the speedo goes into place the ring comes out of the helmet. I have tried fitting the ring to the speedo first and then to the helmet but it refuses to go in. I have used washing up liquid and bad language but i have had to admit defeat. The rubber ring seems very hard and 'plasticy' and i am now considering boiling it in water to make it softer but i would prefer to ask for the advice of someone who has mastered this black art before i try again.

I would be most grateful for any advice. Thank you. Richard.

Answer 1

silicone spray is the best thing to use on rubber. Also a blunt edge (butter knife) can help. Most rubber seals are made with a small side. It may be hard to see but if it is the last part to be inserted it CAN make a big difference. A tire (for example) can only be installed from ONE side of the rim and people installing the tire know what to look for.