Re: [bolger] Oldshoe, the aluminum version - more issues
.
Took the aluminum Old Shoe out Friday.
Weather was worse than predicted. Had about 15 mph winds. 1 to 2 foot chop.
Heading upwind with the 50 lb thrust trolling motor in those conditions was pretty marginal. Rough ride and more importantly pretty slow. The other day in pretty calm seas and about a 10 mph headwind we did 2.8 miles per hour. Under these conditions we were doing 1.4 mph ( masts up with sails tightly furled...would be interesting to see performance with masts down...but taking that tall arsed mast down in a rocking Oldshoe might be a bit too much excitement).
So, it is looking like a trolling motor is looking fine for getting home or cruising around in calm seas and moderate winds....and rather marginal for rough seas and very high winds. For those conditions, I'd WAG that three large deep cycle batteries and more like 100 lbs of thrust would still be workable.
I'd still prefer to use a trolling motor....and probably will when the weather's possible "failure" mode is for the wind to die out. Alas...I also think an outboard will almost be a necessary purchase...
And those waves....they convinced me that this Oldshoe may well have a more proper bow added and which will include something to streamline that wide blunt keel front as well.
Some fun news...my sail repairs held under some pretty strong loads...and I was surprised how little the boat tilted under the loads...managed 4 plus mph fairly easily...even hit 5 mph on occasion.
The bad news?
Those high loads?
Bent the heck out of the mast!
Now I get to fix/re engineer that !
In a perfect world a mast would taper in strength/resistance to bending as you went from bottom to top. What does that "function" look like? Should a point half way up the mast be half as resistance to bending (linear)? Or 1/4 (squared function)? Or 1/8 (cubed function)? Something else?
I'll reinforce this aluminum tube mast by inserting another aluminum tube that goes inside the original and goes a good ways up....then one inside that goes not quite as far up...then another inside that not quite as far...then maybe a final one...or something like that..
Which brings me to one number I'd really need first to start doing some calculations.....what is the max sideways load I could expect on the mast? My guess is that the number I need here is force required to flip the hull sideways (though obviously when the boat is actually sideways....the force on sail goes WAY down)....and then maybe throw in a safety factor of X.
Thanks for any input folks!
And hope to get back to old input later this weekend !
take care
Buddy
Took the aluminum Old Shoe out Friday.
Weather was worse than predicted. Had about 15 mph winds. 1 to 2 foot chop.
Heading upwind with the 50 lb thrust trolling motor in those conditions was pretty marginal. Rough ride and more importantly pretty slow. The other day in pretty calm seas and about a 10 mph headwind we did 2.8 miles per hour. Under these conditions we were doing 1.4 mph ( masts up with sails tightly furled...would be interesting to see performance with masts down...but taking that tall arsed mast down in a rocking Oldshoe might be a bit too much excitement).
So, it is looking like a trolling motor is looking fine for getting home or cruising around in calm seas and moderate winds....and rather marginal for rough seas and very high winds. For those conditions, I'd WAG that three large deep cycle batteries and more like 100 lbs of thrust would still be workable.
I'd still prefer to use a trolling motor....and probably will when the weather's possible "failure" mode is for the wind to die out. Alas...I also think an outboard will almost be a necessary purchase...
And those waves....they convinced me that this Oldshoe may well have a more proper bow added and which will include something to streamline that wide blunt keel front as well.
Some fun news...my sail repairs held under some pretty strong loads...and I was surprised how little the boat tilted under the loads...managed 4 plus mph fairly easily...even hit 5 mph on occasion.
The bad news?
Those high loads?
Bent the heck out of the mast!
Now I get to fix/re engineer that !
In a perfect world a mast would taper in strength/resistance to bending as you went from bottom to top. What does that "function" look like? Should a point half way up the mast be half as resistance to bending (linear)? Or 1/4 (squared function)? Or 1/8 (cubed function)? Something else?
I'll reinforce this aluminum tube mast by inserting another aluminum tube that goes inside the original and goes a good ways up....then one inside that goes not quite as far up...then another inside that not quite as far...then maybe a final one...or something like that..
Which brings me to one number I'd really need first to start doing some calculations.....what is the max sideways load I could expect on the mast? My guess is that the number I need here is force required to flip the hull sideways (though obviously when the boat is actually sideways....the force on sail goes WAY down)....and then maybe throw in a safety factor of X.
Thanks for any input folks!
And hope to get back to old input later this weekend !
take care
Buddy