On boat ownership

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Re: On boat ownership

Postby KingsTransom » Tue Sep 13, 2016 2:22 pm

The mast is 22 foot, one eighth inch from the bottom of the tabernacle to the top of the masthead casting.
The mast foot is 27-1/2 inches long.
I have not found any precise specifications for the mast, so perhaps someone here could measure their mast for comparison.
I believe the sails are the originals. The label says "Made for O'Day of Bainbridge by Neil Pryde". There is a big red DS logo near the top of the mainsail.
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Re: On boat ownership

Postby DigitalMechanic » Tue Sep 13, 2016 5:34 pm

I measured 22' 1" from tabernacle to bottom of masthead. So, I would say 22' is right in the ballpark. Then the tabernacle itself sticks up out of the top of the cuddy/deck 3-4". Neil Pryde did make the original sails (I have a pair that came with the boat, lol). I am not sure that the the bottom mast height matters more than to push the tabernacle roughly a few inches above deck (but could be wrong). The tuning guide says that you want to distance between the transom of the boat and the highest part of your mast the halyard can reach to, to be 25' 1" to 25' 2" when all pressure is applied to the rig (forestay and sidestays). That might help get things in a good starting place. Also, I know that pulling the sail up on my boat can be a challenge (I need to replace my masthead sheaves). It may simply be that you did not get the sail all the way up. Not sure about you, but I have another block at the bottom of the mast to give some extra purchase on raising the main sail. Anyway, I would play with it on the trailer some. Do some dry sailing! ;)
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Re: On boat ownership

Postby KingsTransom » Wed Sep 14, 2016 6:50 pm

The masthead casting is 2" tall, making your mast almost 3" taller than mine. Interesting if that difference is just variation, or if there is some reason for it. I see no evidence that my mast was cut, like crude ends or stay adjusters near their shortest point of travel. The sail and the boom are both on the mast proper so yes, a taller mast foot would do nothing more than push the whole rig up some. There is one cheek block on each side of the mast, just above the tabernacle. Once near the top, I cleat the halyard and pull horizontally on the vertical part of the halyard (like a bow & arrow) to get some mechanical advantage.

Short of using a surveyor's transit, how would one measure from the transom to the top of the halyard's travel?

I tried to straighten the mast, or at least spread the narrowed track for the bolt rope. I put a milk crate and a sandbag beneath the bend, with the bend facing down. I hung 40 lbs from each end and used spreading pliers to open the bolt rope track. I don't believe the bend or the narrowing was improved at all. Since the sail runs freely past that point, I think the best fix is no fix at all.
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Re: On boat ownership

Postby GreenLake » Wed Sep 14, 2016 7:11 pm

Removing a bend in a mast requires something like a crew member's weight at several feet of lever arm. I gently balanced on mine and walked back away from the bend (carefully observing the distance at which change started showing up, so as to not overbend the mast). My bend was close enough to the end that I used additional weight (40lb cat litter boxes in each hand :oops:) to get to just the correct bending moment required.

No fix may still be the best, because wrong fix will = lost mast.

You can lead a halyard to the transom to measure the fore/aft distance of mast tip from transom. You can weigh one down with a shackle and let it drop to the deck (boat must be in water) to check how far the mast tip leans left/right and also to check on the mast rake (some leaning backwards is desired).
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Re: On boat ownership

Postby DigitalMechanic » Wed Sep 14, 2016 11:40 pm

Lash a tape measure to the main halyard and raise it all the way up. Then measure the distance from the masthead to the transom with the tape measure. You want to be in the ball park of 25' or just short if there is no tension on the rig. Once the rig is tightened down it should be 25' plus an inch or two (give or take). Then take your main halyard and bring it to each chain plate of the side stays and keep adjusting the tension on them until the halyard touches the gunwale chainplate at the same length (on the halyard) on each side to get a straight mast. Go back and check your masthead to transom distance to make sure that it is in the ballpark spec of 25' ish (plus an inch or two). If not tighten or loosen the forestay turnbuckle as necessary. I have a loose gauge to measure the tension, and I have roughly 110lbs on the forestay and 180lbs on the sides tays if I remember correctly. I was told that my rig should be tightened up considerably by a guy who races boats. I told him I would prefer for it to not be that snug considering the boat is 40 years old. He said for cruising it felt fine then. Other racing rigging guides will tell you to go as much as 300-400lbs on the stays. Rudy at D&R told me to just make sure they have a twang when plucked and should go sloppy when the boat heals. I believe that is what the I have at 110/180lbs, and the leeward stay does go sloppy. You have to play with it for a little bit on the trailer to get it close enough to start, and everything lined up. Then go sailing and see if the boat handles correctly. If it does you should get slight weather helm going upwind that draws you into the wind when you release the rudder. The boats natural reaction should be to round up (into the wind) and stall when not under command. If the boat does this correctly, as I previously mentioned you will be able to use the rudder as a gas pedal of sorts. To power up when going upwind, steer the boat away from the wind (pull the tiller toward you), putting more pressure/power on the sail. To power down, let the tiller go away from you (it will do this on it's own), and the boat will draw itself into the wind and begin to stall. Fun stuff. Tweaking it out is not really that bad. I think it took me an hour or so with it set up on the trailer. After you sail you can make minor adjustments if you see fit. But your adjustments on the trailer alone should put you near where you want to be and your next sail should be a good one.

Edit:
Oh, I almost forgot. When you get everything in place, you have to measure the mast pre-bend. You can take your main halyard and pull it straight down to the bottom of the mast and press it to the mast track near the tabernacle or gooseneck (thereabouts). You should be able to see a 1 inch gap between the halyard rope and the mast half way up near the spreaders. If you have a 1 inch gap your rake should be set. If not you will have to tighten/loosen the rig down to bend the mast more/less.
Last edited by DigitalMechanic on Thu Sep 15, 2016 7:43 am, edited 1 time in total.
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Re: On boat ownership

Postby GreenLake » Thu Sep 15, 2016 2:49 am

DigitalMechanic wrote:Lash a tape measure to the main halyard and raise it all the way up. Then measure the distance from the masthead to the transom with the tape measure. You want to be in the ball park of 25' or just short if there is no tension on the rig. Once the rig is tightened down it should be 25' plus an inch or two (give or take). Then take your main halyard and bring it to each chain plate of the side stays and keep adjusting the tension on them until the halyard touches the gunwale chainplate at the same length (on the halyard) on each side to get a straight mast. Go back and check your masthead to transom distance to make sure that it is in the ballpark spec of 25' ish (plus an inch or two). If not tighten or loosen the forestay turnbuckle as necessary.


Nice summary.

DigitalMechanic wrote: When you get everything in place, you have to measure the mast rake. It is essentially the bend in the mast. You can take your main halyard and pull it straight down to the bottom of the mast and press it to the mast track near the tabernacle or gooseneck (thereabouts). You should be able to see a 1 inch gap between the halyard rope and the mast half way up near the spreaders. If you have a 1 inch gap your rake should be set. If not you will have to tighten the rig down to bend the mast more.


Mast rake and pre-bend are two different things. I think you are describing prebend. Mast rake is the angle of the mast and you set it with measuring the distance to the transom (you can roughly check it also with the "weighted" halyard method, measuring the distance between the mast and a the vertical at the deck level - however for that you'd need the boat on the water, for the other methods dry rigging is fine.
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Re: On boat ownership

Postby DigitalMechanic » Thu Sep 15, 2016 7:45 am

Thanks GL! I edited it. Maybe I had a dyslexic moment, maybe it was the wine, lol. :D
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Re: On boat ownership

Postby KingsTransom » Mon Oct 17, 2016 12:50 am

I had her out last Saturday (10/8) afternoon, and she really handled well. The local bouy measured winds of about 6 knots. Blowing into the dock meant I needed to motor out of Burnham harbor and we raised sail once out of the mouth. We sailed from south of McCormick Place north to Navy Pier. One crew member spent the trip laying on his side, watching the Chicago skyline since that helped with the seasickness. I spent some of the time with the other (newbie) at the helm, until the wandering point of sail started to make me feel a little off, at which point I took over. We got to watch the sun sink behind the skyscrapers and the sky slowly fall into twilight. I became pretty focused on making the best speed possible to get into harbor before dark, since the boat has no lights other than a headlamp and an SOS flasher.

Overall the boat was well behaved and fun to sail. I'd like to sail more before the harbors close for the season, but do so with incrementally stronger winds rather than a quantum leap like the 20 - 25 knots expected tomorrow.
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Re: On boat ownership

Postby GreenLake » Mon Oct 17, 2016 2:33 am

Legally, a powerful flashlight to light up your sails (in time to prevent collisions) may be all that is required (as long as you are under sail).

There are various sets of LED lights that you can install to show the typical navigation lights pattern.

I decided to make an adaptor for these lights:
877876
(Not shown in the drawing is the bolt that I epoxied into the middle, to which the lamp gets screwed).

Six knots is great to get the boat moving but very safe with newbies. Perhaps a bit on the weak side if the water isn't flat. Good plan on not jumping to 20 knots the next time.
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