Post by Glenn AUS 719 on Oct 30, 2008 11:06:35 GMT 10
Questions regarding lower bearing location. I noticed last weekend that the new masts have their heel located further forward than where it is for the old alloy's IF the new masts require the lower bearing further forward I will need to relocate the bolts and now is the time to do it before I epoxy everything. Can someone give me some rough measurements so that I can make sure the bearing bolts are located in a good position so that I have room for adjustment.
If you were looking at the new Jason King Boats, they have the mast forward as they have a larger bow. I would not suggest moving yours forward as this will make you nose dive, have a look at the similar hull types to help make your decision.
When I launched my boat I tried it with the mast shifted right forward in an attempt to make the helm nice and light. The further forward it went the slower I got. I then shifted it massively back and suddenly the helm went lighter and the boat got faster...back to front and weird I know but that is how it was. Since the worlds I've shifted it even further back and got faster again.
One of my things now is to get the mast as far back as I can without getting excessive windward helm. Prob having a stiff mast helps here. I think as far as weight in the bow is concerned that is the way to go. But hey that's just my thought. Don't ask me for the measurements because I really don't know what they are. I just set the boat up by feel and go from there. Optimum mast position depends I think on your hull shape in the bow and your rig stiffness.
In my boat i have chocks similar in range at the bottom as I do at the top, hence I can move my mast back and forward heaps.
Post by Glenn AUS 719 on Oct 30, 2008 18:44:05 GMT 10
Thanks Karl, I see the sense in all of this and will keep the design as close as to how it was originally built. Should have about 200mm movement fore and aft both at top and bottom bearing, which from my observations of other OK's should be more than enough. Epoxying in the new base plate tomorrow, then down to the fun part running rigging. All being well will be on the water for trials early next week. Just wish I had my new mast but C-tech have a huge back load and as luck would have it I am near last . There you go.
I'd support Andre and Karls comments. When I had 668 a similar hull shape to yours moving the keel position was risky as you can kill upwind performance. I think I settled on 5mm forward after getting my carbon mast. I'd suggest not moving it until you have somrthing to measure it against.