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<center></center> <b>Lifting a C250 WB off the trailer at home</b> Caption:Looking for a way to get the boat off the trailer in order to do some work on the keel lifting system. Rather than build a series of blocks I'm looking at ways to support the boat on straps. 1st idea is to use 20,000lb 2" tow strap (readily available) supported on 4 legs made of 4x4 timber reinforced with 5/8" plywood. Each leg would have a 4' length of 4x4 along the lower edge so that the ply does not dig into the ground. An 8' 4x4 along the vertical side of the ply. The ply would be half an 8' x 4' panel cut diagonally. The straps would be secured with a piece of ply screwed through the strap and into the vertical 4x4. To provide fore-n-aft stability, 1" straps would run from eyes near the top of the vertical 4x4 to the pulpit and catbird seat supports. The boat only has to raise 10" in order to remove the trailer.
A few thoughts that popped into my head immediately: 2" wide straps seem small for the job, most lifting straps I've seen are more like 6"-8" wide.
How do you intend to attach the straps to the supports?
How do you intend to raise the boat off the trailer?
If you're not going to use the straps to raise the boat, how are you going to (safely) get the straps under the suspended load?
I haven't done any calculations, but 4x4's seem small for the job, but might be adequate for a WB since it's 1500 lbs lighter than a WK (roughly).
How are you going to keep the tops of the 4x4's from collapsing inward as the load comes on? Spreader bars would probably solve that as well as giving you more structural rigidity.
I've thought about doing something similar, but building a cradle out of scrap 2x4's laminated in both directions to create at least a 6" wide cradle for each end and then lift the cradles with a bottle jack and support with stacked ricks of 2x4 or 4x4. That way you only need to move the boat a couple of inches at a time and it's always supported on one end as you jack the other end up & add blocks. You could build a similar cradle using your method, but you'd have to raise the boat that much higher to clear the cradle itself, so it's a game of numbers.
I agree, I've seen and helped lift large boats off trailers using jackstands. Used jackstands (minimum of 4) can likely be had around $200. Craigslist.
The way I'd do it is lower tongue, insert jackstands at the stern. Raise tongue, insert jackstands at the bow.
other option is to jack the whole trailer up, insert jackstands around, lower trailer down, pull out, block keel.
The key is to rest more than 50% on the keel when you are done.
By the way, I think 4x4s are [marginally]fine (but ONLY for vertical use, not any lateral forces). 4x6s work too.. but my concern would be how do you make it "adjustable." If I were "making" jackstands, I'd look at temporary floor jacks... Bound to be an easy way to use them. Most have tilting heads/feet, and you could use a large block of wood bolted to both ends to make it work. Boy I think I just gave myself an idea!
Ok so lets say you wanted to jack up your boat... you'd take a 2x8x16 footer, mount 2 of these "bolted" to that board, on the port and starboard sides of the boat , then block up the "rig" to the height you need. Put a piece of wood (big, say, 12"x12" to build a pad carpet it, for the tops of the jackstands) then crank away... It'd take 4 of these to build your own jackstands, but they'd have no problem lifting this much weight! Oh and I'd chain the heads of the jackstands together (duh), because they'd want to kick away from the boat (again position them at the right points of the boat, and the forces will be more down than out).
but to make the gap wider you could use 12 x 16 maybe 3 should be wide enough to drive the trailer through . I use cement block 6 per side for my WK well 10 per side i like to lock the block together doubled up . then you have to chain front to back both side so nothing slips ..
maybe just taking it to the yard and paying for lift time might be cheaper :) then again finding a way is half the fun !!
Or you could back the trailer with boat on to some planks of wood say 8" high that way you only have to jack the boat and trailer up a couple inches ... then remove planking and lower the trailer 10 inches .
Thought provoking ideas with lots questions and unknowns...
Not so simple to come-up with a safe, serviceable, in-expensive, do-it-yourself, store-away, back-yard solution.
Assuming... 1) C250 WB gross weight is about 3000lbs without trailer 2) The mast is in down position 3) Trailer to be removed forward once the boat is suspended and secured above the trailer 4) Center board is in "up" position 5) Somehow braced for sideways motion 6) Weight, bow and stern secured without damaging the hull (not sure how...)
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">here are some photos to give you an idea for supporting the boat <hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
As I wrote above, I would use jack stands at the stern and the heavy beam at the bow. I added the pics primarily to show the beam and swivel pads. I tossed in the pic of the drums to show how it could be done, assuming the drums could handle the weight of a C250 WB. We also have one fleet member who works for an electric utility company. He got 1 or 2 surplus electric poles, cut 4 pieces long enough to plant in his backyard, and made his own lift. Note that in the last photo, he used 2 solid concrete blocks to distribute the load evenly. Might be useful to place solid blocks on the bottom also.
I think the photos offer some insight into how it could be done relatively safely. I see a bunch of point loading that looks scary, like sitting on the edge of the 55 gallon drums, and on the edge of the cap blocks. Both look prone to catastrophic failure, if they could be switched to straight compression loads (which the blocks are designed to with stand, not so much the drums), you'd be much better off. I like the swivel pad arrangement, it seems like you could make up a set of four, use three to get the boat up off the trailer and the fourth to swap out as you moved the trailer forward (I'm thinking about my WK now, it'd be simpler with the WB because you don't have 3' of keel sticking down). In my case for what I'd want to do (paint underneath the trailer pads), I just need to be able to go straight up enough to be able to get under the pads (which can be dropped) by a few inches to get a tool in there to clean it, and then paint. I don't need to remove the trailer, at least I don't think so. When I did something similar last time I painted, I scared myself hearing all kinds of cracking noises as I tried to lift the stern, so I didn't. I got the front four pads cleaned out from under, but opted to leave them unpainted as I didn't want to further stress my hull with lifting it again. So now I'm sure I've got six little 1' square patches that are pretty much covered with marine growth again.
Have you given any thought to a wrecker service, ie tractor trailer type recovery vehicle? They are more than capable of lifting your boat off the trailer and setting it onto stands at your house, if the space permits. Maybe you know someone in that line of work. They are always looking for ways to advertise their business. One local tow company here lifted a medium size airplane that had gotten stuck off the edge of a runway. Those guys make their money on rolled-over tractor trailers and the insurance companies...not on stuff like this. Just a thought....and they make like the challenge and free advertisement.
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">1) What type of material did you use for shaping to the hull 2) Can all joints be dissembled for storage? <hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
I made the hull shape from that thin plywood frome Home Depot its already cut 2`x4` 1/4 thick , then i glued 3 of them together with Gorilla glue .. while there still wet i made like i was going to lift the boat and it forms to the hull .
I let it dry over night and it holds it shape .
2- the hull piece comes off that i store inside , the rest stays out side ..
I like the pictures Dave put in being lower to the beam I think is better , i made mine taller so i wouldnt have to stack so many blocks .. and daves look like the swivel thats nice too , mine dont move .
the way i have it with sailboat stands in the back and the support in the front it seems presure is pushing the boat forward . (for me its ok because im just painting under the pads)
if i was to do what paul wants to do maybe lift it with a beam pull the trailer out then place 5 sail boat stands like the yards does then there is plenty of days to get the job done .
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.