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Lifting an FT10


Bedford

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Has anyone devised a way to lift an FT10 from a single point? Is there a mod that's worked? There's a guy here that wants to put a hole through the main stringer aft of he keel and run the strap through it. I think it's a disaster in the making.

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The way to do it to lift it from the top of the keel. That is the way it was designed to be lifted. Only thing it needs is a lot of weight on the bow to balance the boat.

 

What about the keel and a line aft to balance it?

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While reading this thread and thinking that we had jaw boned this topic to death, I had an idea.

 

What if while the boat is floating

the keel was lifted almost all the way up by a single point launching crane,

a boat strap was passed around the hull a few feet back from the fin and attached to the crane hook to keep the boat balanced,

and the boat was than lifted out of the water.

 

To launch reverse the procedure.

 

I know that this can be done because I have hauled and launched the boat using different methods, including two straps led to a single point lift.

 

Tom Hirsh would certainly have an opinion in regards to this method, since he has also used straps.

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I have been thinking that a wedge placed just behind the fin could solve the problem of the hull rocking back on the keel bulb as it tapers aft. The hull is totally independant of the keel until they come into contact with each other, the bulb taper aft allows the hull to rock back as they come together . The wedge would keep the hull level and not allow it to rock back as contact is made during the lift. It could be enough to have a level lift. Unfortunately I don't have a single point lift in the area to test the idea. If the idea works, the wedge would be dropped in the water at the stern and walked forward with a couple of straps which would hold it in place.

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While reading this thread and thinking that we had jaw boned this topic to death, I had an idea.

 

What if while the boat is floating

the keel was lifted almost all the way up by a single point launching crane,

a boat strap was passed around the hull a few feet back from the fin and attached to the crane hook to keep the boat balanced,

and the boat was than lifted out of the water.

 

To launch reverse the procedure.

 

I know that this can be done because I have hauled and launched the boat using different methods, including two straps led to a single point lift.

 

Tom Hirsh would certainly have an opinion in regards to this method, since he has also used straps.

The guy waiting in line behind you at the crane might have an issue with this. Does a bridle from the top crane hook to the aft corners of the boat not work?

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While reading this thread and thinking that we had jaw boned this topic to death, I had an idea.

 

What if while the boat is floating

the keel was lifted almost all the way up by a single point launching crane,

a boat strap was passed around the hull a few feet back from the fin and attached to the crane hook to keep the boat balanced,

and the boat was than lifted out of the water.

 

To launch reverse the procedure.

 

I know that this can be done because I have hauled and launched the boat using different methods, including two straps led to a single point lift.

 

Tom Hirsh would certainly have an opinion in regards to this method, since he has also used straps.

The guy waiting in line behind you at the crane might have an issue with this. Does a bridle from the top crane hook to the aft corners of the boat not work?

Sure it works, but what would you rather have

* bridle pulling out hardware attached to the hull/deck joint

or

* boat strap supporting the hull from underneath.

 

As to those waiting for the haul out, there is the inevitable delay after the keel is lifted all the way up before one can tighten the aft bridle and continue to lift the boat.

 

The unattached boat strap can be put in place before lifting the keel.

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The strap thing could work and #062 uses it but they had to build a beefy I-beam to keep the strap from crunching the edge of the deck. The other thing is how to prevent the strap from moving fore/aft.

 

A possible quick lifting solution: A "T" shape bracket (looking from top down) with 2 pulleys. Hull strap (4" webbing) goes on the two ends of the horizontal stroke of the "T". Pulleys are set along the vertical stroke of the "T". Pulley 1 is in line with the CG of the boat about at the mid-point of the bracket. Pulley 2 is in line with the lift point of the keel. A beefy spectra strop runs thru both pulleys.

 

To operate -- set up hull strap and "T" bracket, hook up lifting strop to keel lift point and club crane. Crane will pull the strop -- tightening the webbing strap against the hull and start pulling the keel up. Once the keel contacts the hull, the strop now transfers the load from the hull strap and the whole thing is lifted.

 

This will reduce the amount of of load on the bulb and keep things better lined up during the hoist.

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The strap thing could work and #062 uses it but they had to build a beefy I-beam to keep the strap from crunching the edge of the deck. The other thing is how to prevent the strap from moving fore/aft.

 

A possible quick lifting solution: A "T" shape bracket (looking from top down) with 2 pulleys. Hull strap (4" webbing) goes on the two ends of the horizontal stroke of the "T". Pulleys are set along the vertical stroke of the "T". Pulley 1 is in line with the CG of the boat about at the mid-point of the bracket. Pulley 2 is in line with the lift point of the keel. A beefy spectra strop runs thru both pulleys.

 

To operate -- set up hull strap and "T" bracket, hook up lifting strop to keel lift point and club crane. Crane will pull the strop -- tightening the webbing strap against the hull and start pulling the keel up. Once the keel contacts the hull, the strop now transfers the load from the hull strap and the whole thing is lifted.

 

This will reduce the amount of of load on the bulb and keep things better lined up during the hoist.

Sounds like a good idea; would you post drawings.

 

I have hauled FT10 using two 4" straps attached to crane hook just above the boom height with no damage to the the edge of the deck.

 

I wonder if Tom has had the same experience using two 4" straps?

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The strap thing could work and #062 uses it but they had to build a beefy I-beam to keep the strap from crunching the edge of the deck. The other thing is how to prevent the strap from moving fore/aft.

 

A possible quick lifting solution: A "T" shape bracket (looking from top down) with 2 pulleys. Hull strap (4" webbing) goes on the two ends of the horizontal stroke of the "T". Pulleys are set along the vertical stroke of the "T". Pulley 1 is in line with the CG of the boat about at the mid-point of the bracket. Pulley 2 is in line with the lift point of the keel. A beefy spectra strop runs thru both pulleys.

 

To operate -- set up hull strap and "T" bracket, hook up lifting strop to keel lift point and club crane. Crane will pull the strop -- tightening the webbing strap against the hull and start pulling the keel up. Once the keel contacts the hull, the strop now transfers the load from the hull strap and the whole thing is lifted.

 

This will reduce the amount of of load on the bulb and keep things better lined up during the hoist.

Sounds like a good idea; would you post drawings.

 

I have hauled FT10 using two 4" straps attached to crane hook just above the boom height with no damage to the the edge of the deck.

 

I wonder if Tom has had the same experience using two 4" straps?

 

 

 

 

 

 

 

You have to be very careful lifting the boat that way. You may not see any immediate damage to the edge of the deck but you are severely stressing the hull/deck joint in a way it is not designed to take load - you could weaken the joint and see the failure later.

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all you need is 150 pounds on the bow. Buy some large jerry jugs and fill them with water and lift from the keel eye..Its easy and works....

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It takes a full trash can and then some on #22. The ideal single pick point is about 9" back from the back of the cabin house keel cover but we are finding that having to crank the aft lines on with the keel not fully up is not helping the trailing edge of the keel.

We are thinking about making up a hard rubber protector to fit in once the keel has been lifted clear of the trunk gasket.

 

The main problem is the keel has to come up straight then add the aft lines. We're working on a better solution since we are now dry sailing the boat.

 

Speaking of lifting and related issues - have those here who are dry sailing had problems with the delrin crank down rods bending? The port forward rod was fixed once and is now bent again. We back off the adjuster bolts each time but am thinking that maybe we should leave them set with the delrins in place.

 

-Snap

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Chris,

008 has gone 2 full seasons dry sailed and never bent those rods. We generally do not tighten them that much -- I use the shortest wrench handle and hold it mid handle. The Delrin wedges provide tons of leverage....my fear has always been over tightening and crunching the keel box from within.

 

Clew

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Clew and Snap & others...

I never touch the adjustment screws when I lift or launch. I have never experienced any keel movement underway either. I always thought that the system was designed as such so we did not have to mess with those once set.

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Kirk,

That is not correct. To lift the keel you must back off those 4 bolts/rods to retract the delrin slightly.

In reverse, after dropping the keel down, you need to tighten those 4 rods (a bit beyond hand-tight but not more) in order to stop any slop/movement in the lower part of the keel box.

 

If you thought the boat prerforms well already, you may notice even better performance once tightened up ......

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I will have a launch system worked out for Prowler in the next few weeks that will mimic the M32s. It will use a lifting bar, more of a triangle, that will lift the keel straight up and move the center back the required distance. I am going to use four spectra lines off the trailing end two to each side's spin pad eye and reinfoce those with G10 backing plates. I am going to build some delurimn shims to fit the keel box to protect the keel as well. The bar will look something like this:

 

http://www.melges.com/images/?s=store/prod...9.jpg&w=600

 

I would welcome any feed back.

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I will have a launch system worked out for Prowler in the next few weeks that will mimic the M32s. It will use a lifting bar, more of a triangle, that will lift the keel straight up and move the center back the required distance. I am going to use four spectra lines off the trailing end two to each side's spin pad eye and reinfoce those with G10 backing plates. I am going to build some delurimn shims to fit the keel box to protect the keel as well. The bar will look something like this:

 

http://www.melges.com/images/?s=store/prod...9.jpg&w=600

 

I would welcome any feed back.

 

Kirk,

 

I'd be interested in a set since it looks like it might be the solution. There will be lots of pressure on the cabin house but that hasn't been an issue yet. I haven't seen the M32's up close but would think ours would need to be a little bit longer to drag the pick point further back.

 

Snap

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I do too, I am borrowing the bar from the M32 at our club and will use it to figue out how our's should look. My one concern is if it is too long it won't clear the bridge on the house as we lift the keel.

 

Good point. Maybe an extension that gets bolted on once the flange clears the house? The loads are not as great as the keel pick.

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I do too, I am borrowing the bar from the M32 at our club and will use it to figue out how our's should look. My one concern is if it is too long it won't clear the bridge on the house as we lift the keel.

KK,

 

The bar should clear easily because it will be vertical until the top of the keel clears the cabin top slot. Only then will the 2 after-guy attachments start exerting tension, causing the bar to rotate aft. until horizontal.

 

The actual length of the 2 after-guys needs to be determined when the bulb is flush with hull and the bar is laying horizontal on the keel plate attached to the keel lift point. That is best done on the trailer.

 

It would be best if the bar was made of SS just like the shackles, so that there is minimum elongation of the tree attachment holes that pivot.

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GP,

 

It is not going to be vertical, close, but because the attachment points will be at the lower back edge and the top of the middle of this device. Also, I think it would be triangular in design like the M32 to give it the rigidity it needs in both directions. So there is a distance offset as we pick up the keel before the strops take up and the device becomes horizontal. The dimensions between the three points of attachment and specs on the bar need to be worked out still.

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Snapper, How are you bending those rods like that? Are the delrin wedges possibly getting hung up as you are lowering the keel down? Those rods should never need that much pressure on them. Are you loosening them up enough so the wedges can retract? Do you have the bungies on the wedges to pull them up so they do not catch? I don't think the rods are bending as you are tightening the bolts as I am not sure that they would even rotate as much as they are bent.

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GP,

 

It is not going to be vertical, close, but because the attachment points will be at the lower back edge and the top of the middle of this device. Also, I think it would be triangular in design like the M32 to give it the rigidity it needs in both directions. So there is a distance offset as we pick up the keel before the strops take up and the device becomes horizontal. The dimensions between the three points of attachment and specs on the bar need to be worked out still.

Note that the Melges design is not a true triangle due to the offset needed so that it can rotate through a 90 degree angle (from vertical to horizontal) at the fulcrum hole.

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I think you should listen to Capt'n Kirk.

He is smart and he knows what he is talking about. He is conservative.

 

Christian: glad to see you still here. You are a hoot.

 

Thanks Roberto, The last time someone said that about me was....? I do have a few very smart friends who have been holding my hand though this. Something like this or close will work I feel.

 

Oh Yea and....

 

GO CANUCKS GO!

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Snapper, How are you bending those rods like that? Are the delrin wedges possibly getting hung up as you are lowering the keel down? Those rods should never need that much pressure on them. Are you loosening them up enough so the wedges can retract? Do you have the bungies on the wedges to pull them up so they do not catch? I don't think the rods are bending as you are tightening the bolts as I am not sure that they would even rotate as much as they are bent.

 

The only rod that is bent is the port forward one. I am having a new one made. Yes we have bungee for the wedges. I have always operated the hoist so will hand off and take a closer look next time we go in.

 

We crank the adjusters all the way down for a tight fit.

 

Snap

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Kirk-

 

I'm interested in what you're doing- we were doing some napkin art last week that looked very much like what you're designing. One thought- the higher off the keel the triange is the steeper the angle to the back of the boat- putting less horizontal stress on those attachment points. Are you thinking about going off the rear pads and grinding down the triangle to the lifting position? Keep posting your ideas.

 

Mark

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All right, well it is now obvious to me that I need to talk to someone because I took the ficken rods and windchimes off the keel. I didn't know what purpose they served at all. They did keep the keel from going all the way down at times. How should they be attached? Mine where held on by a little piece of bungie, other than that they just floated around (why we called them windchimes). Any good pics for them out there?

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The metal parts are used to press the delrin wedges downwards onto a ramp to take up any play between the keel stub and the keel trunk. Without them, the keel will sway a bit more since the only secure attachment is now on the top SS flank.

 

I would recommend inspecting the lower keel trunk (where it joins the hull) to ensure everything is still 100% OK. Better safe then sorry here.

 

Clew

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Snap- "We crank the adjusters all the way down for a tight fit."

 

There is a reason why they are called "a d j u s t e r s". As Clew pointed out you are driving the delrin wedges together and outwards. The keel box is only so wide and once those wedges are driven to that width, it's as far as they are going. There is no need to crank them on fully unless you have already damaged the keel box by over tightening, or want to bend and destroy things. Look over the setup and figure it out how it works before you do permanent damage.

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Here's a question - bear in mind that I haven't looked that close at the boats, I sail on the M32 that Kirk is borrowing the gear from.

 

How important structurally is the piece of cabintop between the keel lifting hatch and the companionway hatch? If this piece could be cut out and made removable, ie. the keel cutout could be extended all the way back to the companionway, you could bolt a couple of chainplates inside the boat somewhere near the companionway steps and mimic the Melges system exactly, saving the need for a really long lifting bar, avoiding damaging the cabintop, and probably simplifying a bunch of other stuff at the same time.

 

I got this idea from the SR21, which had a cutout along the cabintop much like this to assist in raising/lowering of the keel-stepped mast. Obviously this is a much higher load sort of boat, so my concern would be that that piece of cabintop is holding the two sides of the boat apart in this area?

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Snap- "We crank the adjusters all the way down for a tight fit."

 

There is a reason why they are called "a d j u s t e r s". As Clew pointed out you are driving the delrin wedges together and outwards. The keel box is only so wide and once those wedges are driven to that width, it's as far as they are going. There is no need to crank them on fully unless you have already damaged the keel box by over tightening, or want to bend and destroy things. Look over the setup and figure it out how it works before you do permanent damage.

 

The keel box is fine. The port side rods are bent with the forward one being the worst. Probably because they are not the same length. New ones being made. Problem will be looked at a little closer next time we go in.

 

-Snap

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