Association Forum - Shoot holes or Fill in Blanks

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Shoot holes or Fill in Blanks

New Topic

Topic Locked

Printer Friendly

Author

Topic

Page: of 2

Champipple
Master Marine Consultant

Member Avatar

USA
6855 Posts

Initially Posted - 01/29/2008 : 19:12:49

I have a friend who lives on a river that is a tributary to Lake Erie. He has a dock in his back yard but is relegated to power-boating because of the bridges he needs to go under to get to his home. We’ve come up with the following plan and knowing how adept this group is at playing devils advocate I wanted to run it past you.
Goal: Raise and lower mast easily, single handed with zero to minimal physical effort and in very short timeframe – say 5 minutes. Be able to sail the boat safely with little to no impact from the stuff we used.
For sake of discussion, the boat we are would be a swing keel 25 but any deck stepped mast that is hinged such as the 25 would do. Money was not considered, though getting Bruce Farr to just design a boat was considered out of the question.
Concept:
Two gas lifts, Similar to car hood or trunk Lifts, length and lifting capaacity still unknown but guessing 20 or 50 pounders, would extend from the mast forward and connect to a fitting on the deck. The mast, which would be dropped forward would be able to be lifted and held at Z degrees above the deck with these lifts.
The lowers would need to be quick release and the uppers would need to be some sort of quick tightening shroud.
Windlass mounted somewhere in the cockpit would lift the mast once the gas lifts did there job for the first couple of feet. Once the mast is up, the backstay would be disconnected from the windlass and connected to a bridled adjustable backstay system.
Lowers could then be connected.
Other considerations:
Vang, sheets and halyards would need enough slack to allow the mast to go all the way forward.
Topping lift must be capable of lifting boom parallel to mast (possible gooseneck modification)
Probably would want a roller furler
Location of windlass in cockpit still unknown.

Please shoot some holes or fill in the blanks

D. Wolff
DPO C25 Hull 401
Currently Sailing "Champagne and Ripple" 1982 O'day 30

Chief Measurer 2002-2006
Vice-commodore 2007

Edited by - Champipple on 01/29/2008 19:14:37

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 01/29/2008 : 21:17:48

Remove the aft lowers only, tension release levers on the uppers. Run a tight line from the end of the boom to each aft chainplate when the mast is lowered and fix that length. With the mast lowered and supported @ 20-30 degrees,both lines to the chain plates and topping lift attached, haul the mainsheet using the boom as a gin pole. The lines to the chainplates will slacken as the mast comes up, so you may need a hand on the boom. But as those lines slacken, the forwards and uppers will tighten to stabilize the mast.

It is the opposite of what I do when rigging the boat. I have a molded fitting on the forward side of the mast foot to hold the boom, attach jib halyard, lines to the forward chainplates, and main sheet from the boom to stemhead fitting. The mast is supported on a 2x4 with a roller that hooks over the sternrail and a pin with the rudder removed. It is easy with 2 people, but I did it alone yesterday and it worked ok, but not effortless. I inherited the system from the PO - it works, but I can see changes coming - like running the mast forward instead of aft to avoid moving the boom, mainsheet, and rudder (time consuming) or using an A-frame and MastUp. I just need more info on the MastUp - like how high it raises the mast.

And if the boat isn't fixed in stone, when you drop down to 21 -22 ft., the process is much easier. On my Clipper 21, I could lift the mast and walk forward until it was up. The step up to the cabin top got a little tougher in later years, but a 1 or 2 step bench or ladder would have addressed that.

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/29/2008 : 21:25:59

Thanks for the insight Dave. I was never a fan of using the boom like that. Still the tension release on the shrouds and keeping the forwards on is a good note. We also wanted to have an automated system to haul up and down on, thus the windlass.

Edited by - on

dmpilc
Master Marine Consultant

Members Avatar

USA
4593 Posts

Response Posted - 01/29/2008 : 21:28:44

I remember seeing a film about 20 years ago about sailing the canals of Europe. The sailboat in the film had a mast that was hinged to pivot about 1-2 ft above the deck, with a suitable reinforced and anchored mast step that allowed it to pivot at that height. The mast pivoted aft, coming down to a crutch straddling the stern. i wonder if a C-25 could be modified in such a way. To negotiate the many bridges, it could be raised and lowered easily by the couple sailing the boat. Just a thought!!

Edited by - dmpilc on 01/29/2008 21:29:10

britinusa
Web Editor

Members Avatar

USA
5404 Posts

Response Posted - 01/29/2008 : 21:35:30

Great question Duane,
What's the lowest clearance of the bridges at high tide?

Could Electric winch could find it's way into this solution?

Re lowering fwd, I'm guessing, but doesn't the weight of the mast fwd of the pulpit exceed the weight aft of the pulpit?
Is the pulpit up to the weight? (lots of leverage)

Paul

Edited by - on

stampeder
Master Marine Consultant

Members Avatar

1608 Posts

Response Posted - 01/29/2008 : 21:53:04

2 things would have to be clarified:
what boat and what minimum clearance?

To best answer theoretical questions, you need to eliminate as many variables as possible.

I am going to think about this wonderful problem assuming its a C25 swing keel but would need to know what bridge clearance is. These are probably tidal rivers or subject to fluctuation from the Great Lakes.

My first thought would be to forget about the gas struts and put the engineering into the cockpit area where you have more control of the boat. Centralized control is a mechanical maxim. You could have an ~8:1 purchase block and tackle or a windlass (block and tackle could be stored in the rope locker and would be less invasive for sailing than a windlass in a cockpit) with quick release hardware that could be used to raise and lower the mast via the boom as a lever.
I'd make some some Heavy duty, low strech bungees to quick attach to the lower shrouds to prevent side-sway. I would have a hinged mast step. On the forward side of the deck or even attached to the mast, you could put a stopper (purpose built) that would limit the distance (travel) that the mast would go forward and possibly also act as a rest or holder for the mast when it was in its forward-most position. This would necesitate knowing the minimum clearance your boat would have to pass under. This would also be a great safety feature. This stopper could be made of wood with a high density foam cover, or made of rubber - perhaps you could use one or two of those rubber blocks that truckers use to limit the travel on shocks under Gravel Truck boxs.

As an idea, it is very do-able and sounds like a terrific mental exercise. You could modify and expand on it as your experience with your set-up progresses. You need to start with a good concept but you don't have to have the perfect set-up from the outset.

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/29/2008 : 21:57:07

Gas struts should carry some or all of that weight Paul so the pulpit would be up for it. We picked forward for a number of reasons - If we had an automated enough solution, you could do it while going up the river and have a clear enough cockpit to steer (with crew in this particular scenario of course). Plus any gas lift struts would have to stay clear of the boom if we were to drop the mast aft. I also figured that the tacking of the headsail over the struts would be similar to that of the the headsail over the spinnaker pole on the upwind leg.

I haven't actually looked at the height of the bridges yet - that's a springtime thing. But I can tell you that the clearance at High tide is the same as the clearance at low tide.

Edited by - on

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 01/29/2008 : 22:02:06

Duane's about to ask, "What's a 'high tide'?"

How about this?

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/29/2008 : 22:08:13

2 things would have to be clarified:
what boat and what minimum clearance?C-25, not sure on the clearance yet - but I've seen 30 sea rays type doodads, Edgewaters, and other Pilothouse like boats going in and out.

To best answer theoretical questions, you need to eliminate as many variables as possible.

I am going to think about this wonderful problem assuming its a C25 swing keel but would need to know what bridge clearance is. These are probably tidal rivers or subject to fluctuation from the Great Lakes. not much tidal fluctuation....its a lake. Spring run off is the highest followed by dropping depths from there on out.

My first thought would be to forget about the gas struts and put the engineering into the cockpit area where you have more control of the boat. Centralized control is a mechanical maxim. You could have an ~8:1 purchase block and tackle or a windlass (block and tackle could be stored in the rope locker and would be less invasive for sailing than a windlass in a cockpit) with quick release hardware that could be used to raise and lower the mast via the boom as a lever.the boom as a lever again, I'll have to rethink that but I'm not seeing it in all weather conditions. My mental picture is telling me unstable boom flopping all over. Also want to be able to flip a button (not sure where to locate the button) and help guide the mast up and down if single handing
I'd make some some Heavy duty, low strech bungees to quick attach to the lower shrouds to prevent side-sway. givenI would have a hinged mast step.as opposed to the bolt that it already swings on? On the forward side of the deck or even attached to the mast, you could put a stopper (purpose built) that would limit the distance (travel) that the mast would go forward and possibly also act as a rest or holder for the mast when it was in its forward-most position.that was one of the 3 purposes of the gas lifts. stop it from going too far forward, act as a holder, minimize some side sway, and help lift the first 5 feet before the windlass kicks in. This would necesitate knowing the minimum clearance your boat would have to pass under. This would also be a great safety feature. This stopper could be made of wood with a high density foam cover, or made of rubber - perhaps you could use one or two of those rubber blocks that truckers use to limit the travel on shocks under Gravel Truck boxs.

As an idea, it is very do-able and sounds like a terrific mental exercise. You could modify and expand on it as your experience with your set-up progresses. I'dd be sailing my own boat on the lake while he's stuck behind the bridge. He can hone the concept You need to start with a good concept but you don't have to have the perfect set-up from the outset.

[/quote]

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/29/2008 : 22:11:52

Duane's about to ask, "What's a 'high tide'?"
 I almost did, with one of those emoticon things that I haven't quite mastered yet. I think my approach on this one was better. 
How about this? okay - I likey, did we ever figure out how they got the balls to swing out to begin with? Could you pull it off without crew?....I don't think he'll have that kind of clearance though.
but if he did, how would you effectivley fill up the ball

Edited by - Champipple on 01/29/2008 22:12:28

stampeder
Master Marine Consultant

Members Avatar

1608 Posts

Response Posted - 01/29/2008 : 22:19:01

A good machine shop could build a hinged mast step for ~$100. WM has hinged mast steps but I think I would design one and have it built. Properly designed, it could integrate side sway control and possibly have gas strut connectivity.

I've spent a lot of time around machinists and metal shops - I'm always amazed at what they can come up with when challenged with an idea.

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/29/2008 : 22:31:26

you can see the bridge in question in the background of this photo... As you can tell, it is stinkboat clearance only
http://www.vyc.us/Section3/image%20gallery/2004%20Memorial%20day/pages/DSC_9934.htm

Edited by - on

dmpilc
Master Marine Consultant

Members Avatar

USA
4593 Posts

Response Posted - 01/29/2008 : 22:41:20

Perhaps a sailboat with a gaff rig. they have shorter masts.

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 01/30/2008 : 05:53:29

If you hinge the mast about 4' above deck, you could add enough weight to the end of the mast to counterbalance it and make it easier to raise and lower the mast.

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/30/2008 : 06:43:22

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Steve Milby
 If you hinge the mast about 4' above deck, you could add enough weight to the end of the mast to counterbalance it and make it easier to raise and lower the mast.
<hr height="1" noshade id="quote"></blockquote id="quote">

In other words rais the mast step about 4'?

Edited by - on

lewalskim
1st Mate

Members Avatar

USA
70 Posts

Response Posted - 01/30/2008 : 07:18:53

Duane,

I hate to go outside of Catalina but when I was at the St. Petersburg Sail Expo in Nov, I was shown the new Hunter 25 with a shoal draft keel and a mast that could be raised and lowered while on the boat in the water. I asked specifically about doing this in order to go under bridges and the rep demonstrated it on the spot. It is a backstayless design with an interior much like the C250 although not in the same class of fit and finish.

Com-Pac Yachts also had a hinged mast design that was WAY cool that I liked better but with much less interior room on the 23'(?) cat-rigged boat. It was way more expensive too.

I think that these designs would fit your ideas.

Edited by - on

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/30/2008 : 07:25:02

Thanks Mark. I'll take a look, but buying new isn't as fun as creating from spare parts...

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5902 Posts

Response Posted - 01/30/2008 : 07:36:57

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Champipple
 <blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Steve Milby
 If you hinge the mast about 4' above deck, you could add enough weight to the end of the mast to counterbalance it and make it easier to raise and lower the mast.
<hr height="1" noshade id="quote"></blockquote id="quote">

In other words rais the mast step about 4'?
<hr height="1" noshade id="quote"></blockquote id="quote">No. What I'm thinking is to devise a mast tabernacle who's sides are about 4' high, with a bolt through it about 4' above the deck. The mast could pivot on that bolt. The factory original mast tabernacle is U-shaped, and the sides are about 6-8" high. The pivot bolt is at the end of the mast. I'm think about extending the sides of the mast tabernacle so that they're about 4' long, and the pivot-bolt is about 4' high. Weight could be added to the lower end of the mast, to counterbalance the weight of the upper part, and make it easier to raise and lower the mast. The amount of the weight that is added wouldn't have to be enough to equalize the upper and lower parts of the mast. It would just have to be enough to make the weight of the mast more manageable by one person.

Edited by - on

John Russell
Master Marine Consultant

Members Avatar

USA
3444 Posts

Response Posted - 01/30/2008 : 07:51:33

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by lewalskim
 Duane,

I hate to go outside of Catalina but when I was at the St. Petersburg Sail Expo in Nov, I was shown the new Hunter 25 with a shoal draft keel and a mast that could be raised and lowered while on the boat in the water. I asked specifically about doing this in order to go under bridges and the rep demonstrated it on the spot. ....
I think that these designs would fit your ideas.
<hr height="1" noshade id="quote"></blockquote id="quote">
I seem to recall seeing something at the boat show a few weeks ago that involved a set of tubes extending from the mast to the deck that acted like the baby stays on my 250. At least, that's what I thought they were when I saw them. They seem to make sense for an application like this. They'd provide lateral support better than the wire stays.

This past spring, there was a guy with a home built gaff rigged schooner prepping his boat for a trip across lake Erie and out the canals to the Atlantic. He had tabernacles like Steve Milby describes for exactly this purpose. I don't know if he weighted the mast.

Edited by - on

Davy J
Master Marine Consultant

Members Avatar

USA
1511 Posts

Response Posted - 01/30/2008 : 08:04:04

I have a bridge on my canal that has 11' clearance at high tide. I have to raise and lower the mast on the way out and the way in. I do this while underway. I have done it the same way for four years. I have done it single handed, but typically my wife takes the helm and I disconnect/reconnect everything. We use an a-frame. A line runs from a-frame thru blocks back to cockpit. The starboard winch is used to lower and "crank up" the mast. The boom is removed from mast and laid on deck. The mast is lowered to the rear of the boat and then rests on a stainless "frame" that is permanently attached to stern rail. This holds the mast at an angle low enough to clear the bridge. The mast is not disconnected from the tabernacle. Once thru the bridge the mast is brought up using starboard winch. It takes about ten to fifteen minutes to lower, then raise mast and reconnect/tighten shrouds and reattach mainsail. There are a lot of little details to doing this quickly but it is possible to do what you are proposing.

Edited by - on

Nautiduck
Master Marine Consultant

Members Avatar

USA
3704 Posts

Response Posted - 01/30/2008 : 10:05:17

I'm with Davy J. Why re-invent the wheel? People have been using A-frames and gin-poles for years on these boats. Properly configured, and with a stern mast crutch, they meet your criteria. I don't see why you couldn't leave the boom and main on during the operation as well. The boom will pivot.

Edited by - Nautiduck on 01/30/2008 10:07:06

Champipple
Master Marine Consultant

Members Avatar

USA
6855 Posts

Response Posted - 01/30/2008 : 13:18:24

I agree, I don't think the boom needs to come off the mast. Gin poles and A frames are nice, but that is a lot more bulk to have around that a small windlass.

If I rig it right, I suppose I could put the windlass on the bow and run it back through a block to keep it out of the way. Then have it do double duty when at anchor.

Part of the reason for all the autmation and zero physical activity is ease of use. When you have a 15 to 20 minute ride out to the lake and then have to throw in rigging and effort you realize any or all of 4 things. 1. The game on TV is now more inviting than sailing. 2. The dock in my backyard is a waste 3. I can sail in my friends boat 4. With all that work I might as well just trailer.

Edited by - Champipple on 01/30/2008 13:19:02

Davy J
Master Marine Consultant

Members Avatar

USA
1511 Posts

Response Posted - 01/30/2008 : 13:54:41

I have tried leaving the boom on the mast, but because of the angle of the mast needed to clear the bridge, it gets too close to the cabin top. Plus, I leave the sail flaked on the boom, all I need to do is remove main halyard, pull slugs out, lift boom, place on deck. In addition, it makes the mast much lighter to lower and raise. The A-frame stays on deck and in place during sailing, the only thing I do with it is disconnect it from lower foward shrouds. The rest of the equipment needed to lower/raise mast stays in place as well. After raising the mast, the only thing necessary is to reattach forestay, reattach lower foward shrouds, tighten main shrouds, lift boom, install slugs, attach halyard, tighten backstay. Hoist mainsail, unfurl genoa and away we go. It takes about fifteen minutes to reach the bay, all of that is done before reaching main channel, and I am ready to sail. It is not as easy as just letting loose dock lines, but it is a small price to pay to have the boat docked behind the house. The only thing that is really bad about it is, if you take guests, they must stay below while the work is being done, and two, we don't go for short little trips, we go out and sail most of the day.

Edited by - on

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 01/30/2008 : 18:08:09

Have longer upper shroud chainplates made that put the attachment point at the same level as the mast pivot, that will stabilize the mast laterally. Low stretch lines or wire from the boom to the same attachment point and a topping lift will convert the mast and boom assembly to a fully triangulated structure that pivots on a single axis. Release the after lowers and use the mechanism of choice attached to the boom to raise and lower forward. If you didn't mind stepping over it, you could run a compression shaft from chainplate/through mast pivot/to chainplate to distribute loads. For that to work smoothly you would need to radius the foot of the mast

Edited by - on

Bubba
Admiral

Members Avatar

USA
542 Posts

Response Posted - 01/30/2008 : 18:34:46

How about something like [url="http://www.com-pacyachts.com/mastendrpictorial1.php"]this[/url]?
Hinge the mast above the boom. I know the rig that's pictured is lighter than that of a C-25, but maybe the concept would work.

Edited by - on

tmhansen
Captain

Members Avatar

USA
397 Posts

Response Posted - 01/31/2008 : 00:28:06

Check out the mast raising system on the Telstar 28.

http://www.geminicatamarans.com/Exterior_Telstar_Mast.htm

Beyond my ability to afford unfortunately. (my ability to spell too

)

Edited by - tmhansen on 01/31/2008 00:30:05

Page: of 2

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.