Shaft Anodes

[Stemar]

I had to remove a shaft anode recently and it's hollow. Not eroded, but cast hollow - the erosion is on the outside, which does at least suggest it's doing its job, but a hollow anode isn't going to do its job for as long.

Is there a good technical reason for this, or is it just a way of boosting profits at my expense?

 

[rotrax]

Weight reduction.

If solid it would be far heavier. Inertia would tend to keep it rotating when the shaft stopped or changed direction.

As Phil Irving, designer for HRD Vincent Motorcycles once said "We must make friends with inertia!"

AFAIK, we are still trying.............................

 

[jwilson]

I fitted one exactly like that hollow-centre one this morning. I change this every year, along with a prop tip anode. I wouldn't want to keep it in use once it has eroded down as far as the hollow, and I've never had that happen. I do not however remember previous shaft anodes I've fitted having the hollow centre.