by Killick69 » Sat Jul 23, 2011 3:42 pm
Drawing 1 means next to nought to me. From drawing 2 it seems there should be a bush bolted/screwed to a 'flange' Thickness 10mm and 50mm OD (ID = 17?) and material unknown.
From drawing 3 it looks like there is a mounting (brass?) bolted to the keel and it seems a pintle (rod) screws into it and the distance the pintle protrudes is shown, but unfortunately I can't read the dimension. There is a bush (nylon?) of undecipherable dimensions sitting on this pintle.
The pintle is locked by a pin and I guess if the top of the pintle wears, one can remove the pin, screw the pintle out the appropriate distance and reinsert the pin to lock the pintle. Maybe if the pintle is worn/damaged, too short, one could insert a bolt which has been rounded on the end. Probably stainless steel.
What determines the height of the rudder? is it the bush at the top, the bush at the bottom or the pintle. I guess the bush at the bottom and I guess the pintle is just short of touching the end of the recess in the rudder that it sits in. So if bush wears sufficiently, pintle will become the bearing point. Guess the top bush locates the shaft inside the tube, but does not determine height.
A few issues crop up:
dissimilar metals.......s/s and bronze
The bottom bush will be lubricated by water, however, the top one will be dry and will wear faster. The Cassells Marine bushes are rather thin walled, and looking at top of my rudder post thin walls are needed, and this is probably why top bush is nowhere to be seen.
Nylon is not ideal in wet environment. Delron and vesconite dont' swell nor delaminate.
John
