I need everyones help with this engineering problem.....
I am looking to engineer a "lifting tripod" to lift the Nacra mast just high enough so that it reaches past that critical spot where the winch attached to the forestay will lift it vertically. The challenge has always been to be able to lift the mast solo in a controlled way (so that you could stop and anytime to untangle stays or trapwires that invariably catch on something at the most inopportune time) with very little physical strength necessary.
I think first if I could set the mast on the ball and rest the other end on this tripod contraption that is set up maybe 5 or so feet behind the boat on the trailer, and then second attach the winch line to the forestay, and then third lift the mast with a pole that slides up thru the center of the tripod high enough (say 10 feet?)and have it stay there while I could walk to winch to begin cranking I think I would be golden. It would be cool if the lifting action on the tripod could be a winch-type crank too rather than brute force but how to do that completely escapes me.
So what do you think? Maybe someone already does this?
Maybe it would be easier to just engineer a gin pole to change the angle and reduce the amount of lift required to get the forestay winch action to lift rather than pull?
Getting it up is one thing.....and what normally everyone seems to worry about in these discussions but what I want this to do as well, is make it easier and safer coming down. I'm not sure if the Gin pole arrangement qualifies on that account.
Your thoughts?
I am going to try the boat reversed lever idea already posted in this thread but this tripod approach means less changes to the current system.
Thanks
Greg
Jennifer Lindsay built a tripod exactly like what you are talking about, so she can raise her mast herself on her F16 and her A-Cat. Her user name on this forum is jennifert. Send her a private message and ask her how she did it. She is an engineer, I believe.
However, I would think a gin pole would work best for both raising and lowering the mast. I don't know whether any E-Z Steps are still available through some sources, because the manufacturer has stopped making them.
Another way, and maybe simpler than a gin pole, is to have a pole (preferably square tube) that attaches to the trailer tongue right below the front side of the main beam of the boat.
In order to design it, you need to have the mast up in the first place, with the boat on the trailer.
Stand on the boat and reach up the mast. At a point that is as high as possible that you can comfortably reach, mark a place to install a small eye-strap on the front of the mast (or the side of your mast if you have to raise it rotated sideways).
Make your square tube the length that will reach from the trailer tongue to that eye strap.
In the top of the square tube install a captive sheave (that will keep the rope from hopping off it).
So, once you have put the eye strap on the mast and have your pole with the sheave, you attach the pole to the trailer, you run the winch line through the sheave at the top of the pole and attach the hook at the end of your winch line to the eye strap (or tie the end of the line to the eye strap if you don't have a hook). And you ALSO have to be sure to tie the pole securely to the center of the main beam so the pole cannot move forward or side to side.
Then you just winch the mast up or down. You can use the trapeze wires to stabilize the mast from swinging side to side -- they can be tied or attached somehow to the ends of the main beam, which is the pivot point. Or, if you have a helper, one person can winch while the other just stands on the tramp and keeps the mast from swinging.
I hope this makes sense. It works really well -- and EASY. 
The only problem is that the pole has to be fairly long to reach from the trailer tongue to where you can reach on the mast. The one I had was a two-part telescoping pole that collapsed shorter on the trailer tongue for storage when trailering and telescoped up for mast-raising/lowering.
P.S. If your trailer tongue doesn't go straight back that far, you would have to bolt on a crossways piece on the trailer frame for mounting the "mast erector" pole. Oh, well, there are lots of possibilities, and most of you guys are more creative than I.
I've built a tripod using three telescoping extension poles, the kind they sell for using with paint rollers. It works well for holding the mast at whatever height is convenient for whatever it is you are doing. It makes a great heavy-duty adjustable tripod.
I'm not that keen on using the tripod for single handed mast raising for a few of reasons. First, if the tripod is set high and close enough to the back of the boat to get a good angle, there a chance of a one of many dangling cables snagging the tripod and tipping it over into the back of the boat. Dinged a transom that way. Second, at low angles there is a lot of foward pull on the boat. I have my tie-downs arranged to resist this, but I'm not happy with the amount of forward force on the mast step ball. Third, since my mast must be turned sideways at low angles, lifting with the forestay or a trapeze wire does the wrong thing. So, this year I'll be working on a gin pole.
Just some issue to consider. A tripod may be all you need.
Jeff, can you explain how you attached the poles together at the top? are the bottom ends on some sort of keeper line to avoid them spreading out under load?
Rusty
N5.8
I think the best bet is to look at a standard camera tripod. One way to make this would be to cut out a circular piece of plywood and use a pair of angle brackets and a bolt to make a hinge point for each leg. You can then attach a V-shaped mast cradle to the top. Yes, you do need some sort of keeper strings. If the top is too wobbly, you may also need a vertical rod of some sort down the middle attached via keeper strings to each leg. Standard tripods usually use folding bars of some sort for this, but strings will do the job as long as you spread the legs until the strings are taut.
Greg,
I forgot what kind of boat you have, but if I remember correctly it's a Narca. So, what I do may not work exactly for you, but I think it wil help steer you in a more simple direction.
My fore mast support on my trailer is 60" high and mounts to the trailer tounge. I have a Trailex so I ordered the long mast support. I did this initially so I could car top my kayaks and bikes while towing the boat using it for a mast stepping system was a bonus. Anyway, at the top of the mast support, mount a sheave (an old winch drum works great) and mount teh boat winch below it at a convenient height. If you are tall, you can mount the winch up high, but it doesn't work well for dragging the boat onto the trailer that high. Basically, you want the sheave at least 24" above the mast step so it is effective. The higher the better. If I am alone, I use a step ladder to support the top of my mast. The ladder fits nicely under the boat on the trailer. If I have someone with me one of us holds the mast above our heads while the other cranks it up. I use a set of trap wire to steady the mast when it is at a low angle. I tie the off to the front cross bar. After about 45 deg the shrouds can take over.
I try to keep it a simple as possible and use components that can be used for other things as well (like a winch to step the mast and drag the boat onto the trailer).
I have seen lots of fancy systems to step masts out there. Most are too complex and too $$$ to be worthwhile.
I hope this helped somewhat.
I use a 6 foot step ladder, fairly stable with the mast rotated 90 degrees for Nacra or 180 degrees for Blade. Park downhill, use a forward trapeze handle while pinning the forestay and make sure the base is pinned and/or tied down. Keep it simple.
How about this one:
That's not a mast stepping device - it's a house window removal device!
Only thing wrong I can see is: Your sails aren't attached yet!
One question: How fast do you drive away so the knot comes loose from either the window or the mast?
Thanks to everyone.......
I'd like to try Mary's suggestion but I need to extend my tongue back towards the rear of the trailer to give the pole something to rest on. Might still modify the trailer to accomodate that since it seems rather foolproof.
Nick, I appreciate your thought process and yes, I have the Nacra. I'm not sure of the ladder in general terms just because they always seem stable in two directions but not in ALL directions. At least, that's been my experience. That's why I favor the tripod, Jeff. I think the tripod that extends upward and locks in place gives you time to see what is going to catch (shrouds etc.) and fix it AND it gets the mast raised past that point when the forces raise it and not simply put pressure on the mast ball laterally.
Raising this mast safely and easily SOLO is a real challenge for me. I won't let it beat me.
Thanks again,
Greg
Is that from Extreme Makeover: Home Edition?
hi all,
winter now and i have to get my nacra 5.2 off the beach or it could get crushed by snow
as i'm just about always by myself and don't have a trailer or captive mast base i've been thinking about ways to raise and lower my mast, once a season, solo
decided to try the
tip the boat over method
pic attached
1. - set up a 5 foot open ladder by the centerboard trunk of the hull going up
- put life-jacket on top to prevent scratching.
- lift hull to about 6 foot high, balance point, and bring ladder under hull, lower onto lifejacket
2. - go around the other side, position 4 foot steps near spreader
- pull mast and boat over balance point and rest mast on top of steps
3. - unhook fore-stay at bridle
4. - as lower stay is now supporting mast/boat upper stay should be slack, unhook it
5. - this past i cheated and had 2 people for but the solo plan would be to use some rope to tie the mast fore and aft to the lowest parts of the beams so it doesn't pivot around the last stay wire during the next hull lift
- then go back over other side and pull upper hull back over the balance point and lower back onto life-jacket again.
- mast should remain on 4 foot steps. go back around and pull mast base off nylon ball , lay mast down and unhook remaining lower stay, lift hull off life-jacket, push ladder aside and lower hull to sand again for beam breakdown
pic attached THIS time
Erice, my mast base (home made) is not captive. It is basically a cilinder with a half spheric hole that fits the ball. There is a critical angle above which the base will remain on the ball. That ladder could be a good support support to ensure you don´t go below that angle, either for raising or for lowering. I always use a safety line in case it pops out, but I proceed that way. Even with a lower support: the mast cradle of my trailer, which is probably too low. If the beach has a slope (as usually), the bows should be pointing towards the water. That way the mast will rest on the shrouds and you will be able to attach or detach the forestay yourself.
If there is nothing to use as a support, I ask somebody to help me get started, holding the mast from the tip and walking towards me, to get a better starting angle. To lower it, having someone to receive it is more dangerous, sometimes I just let it touch the sand, it will pop out of the ball and the safety line will work, but it goes down smoothly enough (you won´t be able to hold it though, it will fall down). Last time I did it towards the water, I asked my wife to detach the forestay. It´s a good opportunity to check if the mast is still watertight. Make sure that there are no kids around and also do it after disassembling the steering. And stay on the tramp, it´s not a good idea to walk on the sterns, the boat will want to sit on the sterns and raise the bows. (Well, mine is a 5.0, not a 5.2, there might be differences regarding the last issue)
thanks Andinista, will try many different ways of raising the mast solo to get a system going
i've been avoiding anything to do with walking on the tramp so far as most of it's stitching has gone and i was waiting for this winter to sort it out
Ok...you guys are making this WAYYYYYYY too complicated. There is a VERY simple solution to raising a mast singlehanded....
....just get an A-cat!!! ;^) (sorry...couldn't help it....been hangin' around the F16 crowd!! ;0) )
I raise my ARC21 (33ft) mast solo all of the time, crew is always late. I have rigged a gin pole using a trailer mounted winch. My biggest Ah Ha at this time is to use the spi halyard vs the forstay for hoisting, this leaves the forstay free to adjust as needed. Pics available for 5 bucks.
I love that name.....
LOL!