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Single handed mast raising for Hobie 18 using power winch
http://www.hobie.com/au/en/forums/viewtopic.php?f=13&t=26174		 Page 1 of 3
Author:  rexjennings [ Wed Jun 09, 2010 7:03 pm ]
Post subject:  Single handed mast raising for Hobie 18 using power winch
Many thanks to the forum member who mentioned seeing a guy raise his mast with a remote operated winch. That suggestion has given me several more seasons of sailing now that I have a way to raise the mast single-handed!

There are probably many other Hobie sailers out there with shoulders that might not be able to handle another season of hefting a heavy mast.
For those who love to sail and often need to rig single-handed, please take a look at what we put together here using a remote operated winch (Harbor Freight), a 12 volt battery and some misc. cables and sheaves.

First photo shows the mast pined and a winch cable rigged to the forestay, slightly tight.
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Next hold onto the mast with one arm while operating the remote to begin lifting the mast.

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Once the mast begins to rise, keep it centered by hand.
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Check shrouds and trap lines to make sure they remain clear (the usual).
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Stop winch once mast is upright.
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Note the extension on this allows the winch to pull the forestay roughly in line with the attachment points on the front of the hulls. With the winch providing the downward pressure, attaching these pins is easy and much less stressful.
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Here is a shot of the winch mounted and a simple 12 volt battery kept in my gear box.
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I've only used this rig for a couple of weeks now, but so far it has been a huge improvement over hand raising!
I'd like to figure out a way to have the sheave be closer in height to the top of the front mast support for a greater pulling angle.
I'll try to repost with adjustments and changes over this summer season.

Any suggestions would also be much appreciated!

Fair winds!

Update: 6.13 Nice day sailing on the lake yesterday. Noticed something that anyone considering this needs to know. See the photo below of damage to the hulls due to pressure from the rollers. Other posts have indicated it is best to have mast cradles instead of rollers (this is a spare Hobie 17 trailer I'm using). Can't say this damage is due to the winch system or not, but it seems to have contributed to it (only starboard hull showing this damage). After repairs, I'll be replacing the rollers with cradles to more evenly distribute the weight. I'm also lifting on the forestay/furled jib during the initial lift to take pressure off the mast base. Note the ratcheting tie downs which keep the hulls in place during mast raising.
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Author:  jsserene [ Wed Jun 09, 2010 9:33 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
I have the roughly the same set up with the same Harbor Freight Winch. However, I have my winch in front of the mast pole. I run the cable through a block attached to the bottom of the mast pole and than straight up through another block at the top of the mast pole. The cable is than attached to 2 trapeze wires. This allows the forestay to be free to attach the pin and not have to worry about the angle difference.
Author:  nO0b [ Sat Jun 12, 2010 7:42 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
This really seems like a far safer way to do it. But how much lift do you have to give it at first? It seems at such a low angle, all the winch would do is just pull your entire boat forward unless you're doing most of the lifting for the first few feet or so...

Good system though.
Author:  rexjennings [ Sun Jun 13, 2010 6:14 am ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
"This really seems like a far safer way to do it. But how much lift do you have to give it at first? It seems at such a low angle, all the winch would do is just pull your entire boat forward unless you're doing most of the lifting for the first few feet or so... "

Seems that one hand lifting on the forestay/furled jib for the first few feet is sufficient. Note that the ratcheting tie down straps keep the boat from going forward. Also note my addition to the bottom of the post. Hull damage right where the starboard roller is. Other H-18 posters have suggested mast cradles which I'll be adding right away. Fair winds.
Author:  nO0b [ Sun Jun 13, 2010 8:00 am ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
rexjennings wrote:
Also note my addition to the bottom of the post. Hull damage right where the starboard roller is. Other H-18 posters have suggested mast cradles which I'll be adding right away.


That damage could also be due to the use of ratcheting straps in general. It's too easy to tighten them excessively, and the hulls just can't withstand that tension. I don't have ratcheting tie-downs within a nautical mile of my hulls.

I much prefer the cam buckle style. Just easier to deal with overall.
Author:  SicosDave [ Sun Jun 13, 2010 12:26 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
Ditto above - it is too easy to go too tight, I still use the ratchets though, do it hand tight first - tow trailer for a small distance then just take up the slack. Was a post previous that had made cradles to fit on top of his rollers. Good (necessary) mod to do.
Author:  Sailinagin [ Sun Jun 13, 2010 4:43 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
Hey Great Idea! I will definately use this approach. I like that black box mounted up front. What brand is the box?
Author:  danneskjold [ Mon Jun 14, 2010 12:34 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
Rex: Thank you for starting this thread. I’ve been considering a remote power winch to help raise the mast. Currently I use a hand winch with my crew on the winch and I’m raising the mast. :evil: My wife hates raising and lowering the mast. Now to the issue……..

I agree that the ratchet straps may have contributed to your hull damage if they were over tightened. The rollers certainly didn’t help. See this topic for cradles: http://www.hobiecat.com/community/viewtopic.php?f=13&t=10959

Since I’m considering getting this kind of winch my question is: How sensitive is the control of the winch (inhaul/outhaul). The Harbor Freight winch has a 3000lb capacity. If you put that kind on downforce on the forestay with the boat strapped to the trailer you’re putting a lot of down pressure on the front crossbar and forward hull supports. This may have contributed to the crushed hulls.

What if you connected the winch cable to a pair of the trap lines using a heavy duty rubber strap with may reduce the possibility of over-loading the rig with the winch? :roll: Any Thoughts??
Author:  calcommon [ Mon Jun 14, 2010 3:18 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
I have a Harbor Freight winch mounted at the base of the mast step also, its a portable model that I remove for storage, and although it may sound like over kill, I cut a piece of 3" abs (sewer pipe) trimmed one end to cup the front cross bar, and cut the other end to rest at the mast base/trailer tongue intersection. This takes the forward force of the cat and braces it against the mast step base, this requires far less force on straps holding the cat to the trailer, it also positions the cat in the same place each time. I tie off the trap wires to the front cross bar, this prevents the mast from leaning left or right on the way up or down. I lift the mast the first couple feet as this is were the most force is required. My nine year old runs the winch when he sails with me.
Author:  rexjennings [ Fri Jun 18, 2010 7:42 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
The winch has a pretty sensitive control. Stops & starts after about 1 second of pressing the buttons. I think lifting on the mast initially should displace a lot of the downward pressure. Looking at my hulls, the damaged side is/was very thin (the other side seems to have lots of fiberglass still).

Connecting to the trap lines is worth a try. The winch hook stops before any real downward pressure is applied when the mast is raised, so I'd probably avoid the rubber strap (more confident with the steel cable).

The box came with my trailer. I've seen a similar one at Tractor Supply. Great for storing the jib, lifejackets, harnesses...etc.

I just replaced the front rollers with cradles and will be doing some fiberglass repairs soon!

Thank you all for your input! Fair winds!
Author:  JJ [ Fri Jun 18, 2010 9:40 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
The forestay starts at almost no angle.

It appears the pressure of the first number of feet of the lift may be really pushing the front crossbeam down and putting a huge amount of pressure on the hull. That may have caused the hull damage and you may get a repeat even with cradles...

Possibly you could test this by putting something between the trailer rollers or cradle and checking the load at various steps of the lift? Say, for example, duct tape a tennis ball or a partially deflated soccer ball to the roller? Just thinking that the degree to which the pressure crushes whatever cushion you use would tell you there's a problem.

The Mast Stepper III uses a gin pole to divert pressure. Also, I noticed when I began exploring options with mine that the instructions on other Mast Steppers recommended at least a 30" height above the crossbar for the winch or a block for the line from the winch.

I don't know where they got the 30" (that number may not be exact, I don't have the instructions handy at the moment) but I assumed it was to move the pressure to more lift than pull. Instead of more pull than lift. There are some basic physics here that I am not good at... (Avoided higher math like the plague in school.) Maybe someone with more math skills can figure the loads and how they change with the angle of the line.

For me, the loads even with the gin pole arrangement have me somewhat worried.
Author:  bamaH18 [ Fri Jun 18, 2010 11:03 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
This is an issue I must address at some point, because I can't solo lift forever.

I aced statics class while getting a degree in architecture, so I have some input to offer. In my opinion, the method used definitely contributed to the hull damage. Maybe that combined with beach wear on the underside of the hull.

If one wants the "pulling force" to be less than the "lifting force" then the angle from the mast must be greater than 45 degrees. At 45 degrees exactly the forces would be equal. If one adds to lifting manually then it would be greater than the pulling force, though hard to calculate. However with so little angle any lifting done manually is the only reason it works at all. If it was totally flat, which it is not, it would burn out the winch, crumple the mast, or more likely buckle the crossbar before lifting. Assuming the boat didn't move of course or the hulls collapse. With the setup here, if the angle is say 9 degrees, then the lifting force is 10 percent of the force applied by the winch, and the pulling force is 90 percent of the force applied. That's not good. And it looks like less than 9 degrees.


I have a HF winch already, purchased for other purposes but intend to use it on my cat one day. I intend to use a gin pole. But I'm going to mount it on the trailer, not strap it to the mast. At whatever height I make the pole I will fabricate an attachment point on the mast at the same level from the base, without altering the mast itself in any way. This would be 45 degrees. That way when the mast is mostly upright an "upward lift" will not be created, as that would tend to pull the mast up off the base. When lifted fully, the cable would be parallel to the ground from the mast attachment forward to the pole. I'm thinking an angle of 60 degrees at the beginning of the lift would be even better. And only needing to keep the mast centered manually during the lift would make my back happy. Sixty degrees can't be accomplished using the the available wires or forestay since they are so far up the mast the gin pole would be very tall. And I would prefer the lift hardware to be independent of the boat hardware.

Hope I don't sound like a know-it-all, just offering my take on the issue.
Author:  JJ [ Sat Jun 19, 2010 7:17 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
Quote:
This would be 45 degrees.
I am lost? "This" is what? And from what is it 45 degrees?

As you said eariler, the first 45 degrees of mast stepping is the problem. Where the pull is much higher than the lift.

However, I would think that at 45 degrees it becomes almost completely pivot/lift with some but not a lot of pull. The 50% lift/50% pull then would happen at about 22 degrees.

So if the angle between the forestay and mast at the mast tang is 22 degrees or more, at that point, the vertical lift starts to become greater than the horizontal force.

I know when I lift it by hand, if I can get the mast up to about chest height, then I am almost at that magical point where it is more pivot the mast than picking it up dead-lift.

If RJ (rexjennings) were to move the block that the cable first passes through higher on the mast stand or put the top of the mast up higher with a tripod of some sort then that important angle between the forestay and the mast would be bigger. And the pressure less.

I think RJ has got a pretty good setup, btw.
Author:  bamaH18 [ Sun Jun 20, 2010 6:32 am ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
"This would be 45 degrees."

Agreed, that's not a clear statement. I was describing a setup where the lifting cable is at 45 degrees. If the gin pole was at height "x" above the mast base and the cable was attached to the mast at the same distance "x" from the mast base then the cable would be at 45 degrees. The value for "x" can be any reasonable figure, I haven't drawn it out to determine what I would make it.


The first paragraph is more pertinent to the discussion.

In statics calculations, a force acting at 45 degrees is calculated as two equal vectors. One at 0 degrees and the other at 90 degrees. At 22.5 degrees, for this example, the lifting force would be 25 percent of the force applied and the pulling force would be 75 percent of the force applied. And conversely, once the mast was up at an angle of 67.5 degrees the lifting force would be 75 percent and pulling 25 percent.

In both cases this pulling force is acting directly through the pivot, which sees no such force like this at all when the mast is initially lifted manually from the tramp. And when the mast is up off the tramp the pivot begins to feel some force applied to it. But it is from the weight of the mast only, not from the winch that is adding greatly to this force felt at the pivot. Feeling this force through the pivot is what would cause the boat to try to rotate bow down, and that is what would put pressure on the hulls at the roller.


That being said all these statements from your post are correct. The statements preceding these are not, though you have the correct conceptual understanding of the issue.

"........ I know when I lift it by hand, if I can get the mast up to about chest height, then I am almost at that magical point where it is more push the mast than picking it up dead-lift.

If RJ (rexjennings) were to move the block that the cable first passes through higher on the mast stand or put the top of the mast up higher with a tripod of some sort than that important angle between the forestay and the mast would be bigger. And the pressure less.

I think RJ has got a pretty good setup, btw. "
Author:  bruce cornell [ Tue Jun 29, 2010 12:01 pm ]
Post subject:  Re: Single handed mast raising for Hobie 18 using power winch
are your wings regular or magnum ? don't have any idea what the difference between them is, or which wings i just got
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