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I made a may raising system today from stuff I already had laying around the shop. An 8 ft 2x3, 2 5/16" eye bolts, 2 smaller eye screws,a couple 2" wood screws, a scrap of line and main sheet with tackle.
Apparently the whole mast raising/lowering was really stressful on the wife. Now, it's so simple and controlled. This is easily the best mod so far.


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I made a may raising system today from stuff I already had laying around the shop. An 8 ft 2x3, 2 5/16" eye bolts, 2 smaller eye screws,a couple 2" wood screws, a scrap of line and main sheet with tackle.
Apparently the whole mast raising/lowering was really stressful on the wife. Now, it's so simple and controlled. This is easily the best mod so far...
I would strongly recommend that you PLEASE DO NOT use any gin pole out that is made out of lumber. I had a very similar arrangement made out of a 2x4, with multiple eye bolts on both sides like yours. Mine used a winch and strap (instead of block and tackle). I used it to raise and lower my mast at the beginning and end of every season. It worked fine for a few years, but in spring of 2016 I heard a "crack" as I was raising my mast. Since the mast was almost all the way up (where tension was lower), I kept cranking (and praying), since I knew that lowering it would increase the tension again and could lead to catastrophe. Once the mast was up, I removed the gin pole for inspection and was appalled at what I saw. I had carefully calculated all the stresses when I designed it, but I failed to account for how the eye bolts would be torqued within the holes I had drilled. That massive torque caused splitting and separation along the wood grain. I had very narrowly averted disaster. If you use your wooden gin pole built with a 2x3, you will eventually encounter the same problem:

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Thanks for the tip. I used some screws to help alleviate that problem, screwed in from either side and long enough to almost poke out the far side. If it looks like that won't do it then I'll weld up a plate with a ring for each side and thru bolt it. The pole is 8' long to keep the stress down and yet still be able to store it. I'll be sure to inspect it each time though.

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I would strongly recommend that you PLEASE DO NOT use any gin pole out that is made out of lumber. I had a very similar arrangement made out of a 2x4, with multiple eye bolts on both sides like yours. Mine used a winch and strap (instead of block and tackle). I used it to raise and lower my mast at the beginning and end of every season. It worked fine for a few years, but in spring of 2016 I heard a "crack" as I was raising my mast. Since the mast was almost all the way up (where tension was lower), I kept cranking (and praying), since I knew that lowering it would increase the tension again and could lead to catastrophe. Once the mast was up, I removed the gin pole for inspection and was appalled at what I saw. I had carefully calculated all the stresses when I designed it, but I failed to account for how the eye bolts would be torqued within the holes I had drilled. That massive torque caused splitting and separation along the wood grain. I had very narrowly averted disaster. If you use your wooden gin pole built with a 2x3, you will eventually encounter the same problem:
What would you recommend as a material? I am thinking of doing similar for my HobieCat. Granted lot less weight in the mast but would like it to be semi permanent and being it is raised every time i use the boat. I was thinking a piece of aluminum tubing should work.
 

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Tubing would be best.
 
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Barquito
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Our mast tabernacle did not keep the mast in-line laterally. We had to try to support the mast itself to keep it from flopping from side to side. Personally, I think if you are not a little nervous raising the mast, you have not thought out all of the possible things that could happen with a failure. It is worth working to make it as robust as possible.
 

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Our mast tabernacle did not keep the mast in-line laterally. We had to try to support the mast itself to keep it from flopping from side to side. Personally, I think if you are not a little nervous raising the mast, you have not thought out all of the possible things that could happen with a failure. It is worth working to make it as robust as possible.
I agree, if you think of the damage done if there is a failure then wow. Even if the mast on my Hobie were to come tumbling down it could easily kill someone or do a lot of damage to a car. A keel boat's mast would be much worse. I am just trying to make it easier for a fat old middle aged guy to do it by myself. Even if I have people with me they won't likely know what to do anyway so I figure make it as easy as possible for me to do it myself is the safest. I know there are some kits available for the Hobie, but they utilize the post that supports the mast on the trailer, and mine is not high enough so a custom poll is in order.
 

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On my SJ21, the chain plates are in line with the mast pivot point, so the shrouds keep the mast aligned on the way up and down. I have a couple lines for the gin pole to keep it aligned during the process, and tie them off on the deck railing.

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I would strongly recommend that you PLEASE DO NOT use any gin pole out that is made out of lumber. I had a very similar arrangement made out of a 2x4, with multiple eye bolts on both sides like yours.

View attachment 136053

There would be a lot of ways to avoid having this happen. This is more of a design flaw than a material failure issue. Drilling four holes in a row along the wood's grain is why the wood failed.

I agree there may be better options for materials than wood but wood is so easy to come by and work with. If you are trying to push woods limitations like 4 bolts right next to each other you can laminate two boards together, glue and screw. When I want to strengthen some wood I will laminate two pieces of wood with some plywood between. Unless you have unreasonable expectations of the wood or design something wrong, wood should be fine for a trailer sailor mast raising system.
 

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There would be a lot of ways to avoid having this happen. This is more of a design flaw than a material failure issue. Drilling four holes in a row along the wood's grain is why the wood failed...I agree there may be better options for materials than wood...
The torque of any one eyebolt (or eye screw) against its hole is enough to start a crack along the grain. Once a crack starts, it is easy to propagate. This can happen with only one screw. A 2x3 is a poor material to use in a hazardous function like this.

If something bad happens and the lawyers come looking, I want to be explicitly clear that I am in the "do not do this" camp.
 

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HemFir splits easily even stud grade. Use a double 2x4 instead of single 2x4. Through bolt with oversize washers both side.
Use eye bolt and eye nut which will reduce the number of holes by half. Cast eyes will distort less than bent wire. The load should be in line with the eye ring not perpendicular to the eye

Line the drilled hole with a short section of copper pipe as bushing (1/2" ID copper for 1/2" threaded bolt requires 5/8" bored hole) this reduces point loads from the threads on wood.

Western red cedar will split less than hemfir.

The majority of loads on a jin pole are compressive, if using a pipe select wall thickness for compressive loads.
 

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I just had two steel pipes that were hammered flat on the ends. A hole was drilled through each end, and attached to the chainplates at the bottom, and together at the top. A block and tackle gave some mechanical advantage for raising. It helped a lot to have the furling foresail OFF the forestay. The weight of the genoa would put a bend in the forstay that would make the angle required to begin to pull the gin pole difficult to overcome. This wasn't so much of a problem if there was someone to lift the rig off the deck for the first 5 feet.
 

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Cost, free! A guy in an inflatable dink ran hard up on the beach scaring all the women and children that were nearby. Us men folk sensing something wrong ran down to see what was going on. Turned out the plastic garboard plug in the fiberglass transom blew out and as long as he kept the throttle pinned the water would be sucked out. Everyone wondered around the near baren beach looking for something to plug the hole. I went to a friend's boat and got a mushroom type of wine cork. I whittled it down with my pookeet knife and stuffed in his garboard hole. Problem solved, Temporarliy I hope.

Also, thread bump.
 
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