How do I support a 7000 lbs. boat?

[ingalp01]

Ok,

I believe that my main winter project, or more to the point fall project will be to re-finish the bottom of my 25ft cabin cruiser, approx. 7000 lbs.

My question is what is the safest way to remove this boat from the trailer and support it's weight in such a fashion that I can get underneath it and re-finish the hull?

I have some hull blisters, and before I get 9000 different opinions on the "evils" of hull blisters, Keep in mind I have read every piece of literature I can find on the subject, including how to best repair them with glass, epoxy and gelcoat.

I don't need to know about the blisters, just how to safely lift, and hold my boat without spending thousands of dollars to buy / rent, or preferably build my jacks / bunks / supports.

Thanks...

 

[Luhrs28]

Re: How do I support a 7000 lbs. boat?

I don't have a decent photo of it but I can describe how my 28-footer is supported at the boatyard:

- 3 sets of wood blocks (each block about 3 feet long) crosswise to the boat's axis, under the keel, evenly spaced. I'm talking big wood blocks, probably 10" x 10" or so, stacked about 3 blocks high and toenailed together.

- About 6 feet in from the stern there are wood blocks under the 2 sides of the boat, with a long wood block crosswise tieing them together, again all nailed to each other. On top of the wood crossbeam under each side of the boat is an angled steel jackscrew support (angled inwards towards the centerline of the boat) with an 8" x 8" plywood pad on top to protect the hull. These 2 steel supports are nailed into the wood blocks at their base.

It's very important that the 2 side supports are tied together crosswise to the boat's axis so one can't kick out on you. On my boat I was so paranoid about that I ran a big webstrap between them and under the keel and put a little tension on it.

OK so the boat's weight is mostly supported by the keel blocks, and the 2 side blocks keep it from rolling over.

Be safe.

 

[ghamby]

Re: How do I support a 7000 lbs. boat?

You asked for the safest way. Have the yard pick it up with the travel-lift and block it with keel timber and boat yard jack stands.

 

[knehdn]

Re: How do I support a 7000 lbs. boat?

The 26 footer I had, I backed the trailer to where I wanted the boat to finally rest, then jacked up the trailer at the stern and placed cinder blacks at each back corner of the boat till I was close to the hull, then placed a couple of 2x6s (or similar padding) on the blocks and let the trailer down allowing the stern of the boat to rest on the blocks. Then I jacked up the bow under the keel and placed blocks and lumber in the same manner (actually, just a couple inches higher to allow for drainage). Now that it's off the trailer, you move the trailer ahead what ever distance (which may only be a couple of feet) till you get close to the blocks with a brace or axle. You jack up the bow again and move the blocks aft of the brace or axle and lower the boat again and move the trailer ahead again. Continue with the procedure till the trailer is free. It was a bit of a pain, but was able to accomplish it on my own. Probably took me an hour. Just reversed the procedure when I placed it back on the trailer. The last thing I did was place another set of blocks close to the set under the bow and used a 5 foot length of 2x6 to spread out the load under keel. Sorry, couldn't find the pics, but I'm sure you got my drift.

 

[Gerry B]

Re: How do I support a 7000 lbs. boat?

I have done this a couple dozen times over the years. Never had a problem. I learned how helping out at a local marina. This technique is using a roller style trailer. You will need a helper. (My wife has done this with me more times than she cares to think about)
1. Get 20-24 concrete blocks
2. gather several pieces of scrap 3/4 plywood and 2x scrap.
3. you will need to be able to tie the back of the boat off to something so as you move the trailer forward the boat will stay in place. I have used another vehicle, tree, tractor...you get the point.
4. once the boat is where you want it, tied off, you will loosen the trailer wench so the boat may move, have a helper pull the truck forward very slowly until the boat starts to move back on the trailer.
5. when the boat gets a 2.5/3.0 feet overhanging the trailer is when you build up with the blocks in a two blocks chris crossed by two more blocks until you have reached the bottom of the boat. When you get to the top is when you will finish the build up with the plywood/2x4 scraps. You do this build up on both port and starboard side of the boat. I usually use a 3/4 piece of plywood between the blocks and ground to ensure even pressure and square stacking of the blocks. the build up also needs to be as far outside on the hull as possible.
6. Now continue to move the boat trailer forward, you will notice the weight being transferred to the block build up you just made.
7.The boats bow will rise as the trailer is moved forward. When it reaches is highest point is when you will do the next build up right on the keel of the boat. Typically one/ two blocks with scrap wood is all that's needed to reach the keel.
8. As you continue to pull the trailer the boat will come to rest firmly on the keel block you just placed.
9. Once the trailer is move away you will now do a build up at about mid ship on each side to ensure the wind/ boarding the boat etc. will not allow the boat to rock.

Putting the boat back on the trailer is much easier and less stressful. The key to putting it back on is square alignment of the trailer to the boat. Slowly wench the boat on the trailer as a helper either backs the trailer up or does the wench. As the boat moves back on the trailer the blocking can be removed as placed.
Just take your time.

 

[proshadetree]

Re: How do I support a 7000 lbs. boat?

Ill be watching this as I really need to bottom coat mine.

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

Excellent guys, this gives me some good ideas, and I definitely like the idea of supporting the boat directly beneath the keel, so the weight pushes straight down on something solid and then using support braces at the sides to keep the boat stable side to side. I need to replace some rollers on my trailer as well, so this will be great.

I suppose I just finish around the supports, wait til my repairs are solid and dry, then move the supports one by one and finish where they were.

Then reversing the process to get back on the trailer seems easy enough. I basically just need enough room to get on a creeper and roll around under the boat doing my sanding, glassing, epoxy and gel. I know it will be a pain in the *** working from my back, but I can't think of any other way.

I will be using one half of my driveway to accomplish this task.

Keep the suggestions coming, but I think I have a much better idea of what I need to do now.

Doing this myself will save me thousands I'm sure...

Thanks again!

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

Hey there... I know I'm kind of hijacking my own thread, but how do I post some pictures up here, so I can keep others apprised of my progress?

I think it would be great to do some well planned Hi-def step by step pictures of the whole process so that others can follow along if they have the same dilema as I.

Thanks again...

 

[sasto]

Re: How do I support a 7000 lbs. boat?

The 26 footer I had, I backed the trailer to where I wanted the boat to finally rest, then jacked up the trailer at the stern and placed cinder blacks at each back corner of the boat till I was close to the hull, then placed a couple of 2x6s (or similar padding) on the blocks and let the trailer down allowing the stern of the boat to rest on the blocks. Then I jacked up the bow under the keel and placed blocks and lumber in the same manner (actually, just a couple inches higher to allow for drainage). Now that it's off the trailer, you move the trailer ahead what ever distance (which may only be a couple of feet) till you get close to the blocks with a brace or axle. You jack up the bow again and move the blocks aft of the brace or axle and lower the boat again and move the trailer ahead again. Continue with the procedure till the trailer is free. It was a bit of a pain, but was able to accomplish it on my own. Probably took me an hour. Just reversed the procedure when I placed it back on the trailer. The last thing I did was place another set of blocks close to the set under the bow and used a 5 foot length of 2x6 to spread out the load under keel. Sorry, couldn't find the pics, but I'm sure you got my drift.

This method has worked for me on several occasions. I don't like using a floor jack because it has a tendency to lift toward you and not straight up, as a bottle or scisssor jack does.......I wouldn't leave the weight on the keel for any extended period of time

 

[erikgreen]

Re: How do I support a 7000 lbs. boat?

Be very careful using concrete blocks. If you use them wrong they may fail, crack or crumble, and then your boat falls over. If you want to know why, ask the manufacturer for numbers on the compressive strength of each block, and remember that when used in a wall or foundation they support only part of the weight of the building, not 1/4 of 6000 lbs...

If you want a cheap material to block up a boat with, go with wood. I checked out the price on 8 foot 6x6 landscaping timbers recently... $10 each, so cut to about 18 inch lengths I need about $50 worth to block up my boat, and they'll last for years in the weather.

Erik

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

Yeah, I already thought about the cinderblocks cracking or crumbling, but laid two by two and stagger stacked, I think they would be fine.

The Landscape timbers are also a good idea and frankly I am thinking of going the wood route for the ability to attach the pieces together easily and therefore have readymade "stands" if i ever do this again, or for trailer repair. I plan on owning this boat for a long, long time.

Also found this interesting article on "HOW TO.com"

http://www.ehow.com/how_5852457_jack-boat-off-bunk-trailer.html

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

P.S. I have to throw out a big ole thanks to everybody on here.

I have learned a bunch from this site already and am sure I will pick everyone's brains again and again over the years.

Thanks!

 

[Bondo]

Re: How do I support a 7000 lbs. boat?

I wouldn't leave the weight on the keel for any extended period of time

Ayuh,... But that's Exactly where you want all the weight of the hull.....

A hull absolutely needs supporting blocking in 3 points...
As long as the transom is supported at each outside corner(as wide as feasable)..
The 3rd point would be at the Keel, about 2/3s forward of the transom on most hulls...
Another little tidbit,...
If any 1 of the 3 stacks of blocking is lain 90? to the line of the other 2,...
It won't be at All tippy...
As Solid a foundation as possible...

With my 34' houseboat, before I built it's wagon, I hadta block it,...
I added 2 more stacks of blocking running down the keel, as well as stacks at the outside forward corners of the bow under the chines...
Not that it Needed it, but because I could....

 

[sasto]

Re: How do I support a 7000 lbs. boat?

Ayuh,... But that's Exactly where you want all the weight of the hull.....

A hull absolutely needs supporting blocking in 3 points...
As long as the transom is supported at each outside corner(as wide as feasable)..
The 3rd point would be at the Keel, about 2/3s forward of the transom on most hulls...
Another little tidbit,...
If any 1 of the 3 stacks of blocking is lain 90? to the line of the other 2,...
It won't be at All tippy...
As Solid a foundation as possible...

With my 34' houseboat, before I built it's wagon, I hadta block it,...
I added 2 more stacks of blocking running down the keel, as well as stacks at the outside forward corners of the bow under the chines...
Not that it Needed it, but because I could....

You may be right in this situation....as you usually are...but my manual on our 2 boats (although larger) clearly state that no more than 10% of weight should rest on keel while on blocks.....jack stands on the chine are required. I assumed this applied to all boats....Thanks for the clarification....Is being on a trailer different? If the blocks are going to be on the keel shouldn't they be placed at a location where there is a bulkhead? Or does it matter?

 

[sasto]

Re: How do I support a 7000 lbs. boat?

After further review.... I owe the poster an apology for my inaccurate post. Listen to Bond-o.

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

Thanks to all...

In my short time here on the forums, I have come to understand that listening to Bond-O is never a bad thing... LOL...

Bond-O your help and knowledge is invaluable... Now if you can tell me how to post pictures, I'll start documenting some of my projects and sharing.

First one, look for a new Post, will be my Smart Tabs II for big boats install... Happening this afternoon... Water test on Saturday.

Thanks again...

 

[1970 Chieftain V]

Re: How do I support a 7000 lbs. boat?

...

Bond-O your help and knowledge is invaluable... Now if you can tell me how to post pictures, I'll start documenting some of my projects and sharing.

...

I'm not Bond-O but I can help with the picture upload. Upload your pictures to a site such as photobucket. When you are viewing your viewing your picture on photobucket look for the share this image on the left side of the page. Click on the url next to the words IMG Code. Then paste that url into your message.

it will look like this

.

Presto your pictures will be in the post.

 

[knehdn]

Re: How do I support a 7000 lbs. boat?

I'm glad Bond-o agrees with my 3-point storage. I had my 26' Reinell sitting on three points, I also had a 30' Connie resting in the same manner for over two years, and it was a wooden hull, with no signs of any damage to the keel or aft corners. I've also had sailboats (with full keels) resting with all the weight on the keel with the uprights of the cradle there just for balance and bracing. None of these boats sustained any damage from being stored in this manner. The keel's the backbone of the boat - its strongest member.

 

[ingalp01]

Re: How do I support a 7000 lbs. boat?

Thanks for the picture advice. I started a photobucket account and uploaded a test picture this am, but it was huge. I need to figure out the re-size deal. Someone says you can auto re-size them at photobucket anytime you upload, so I will try that when I get home from work today.

Luckily I can access i-boats from work, but not photobucket... Restricted website... Arghhh... But oh well, will get the pics re-sized and up in reference to the Smart Tabs II install this evening.

Thanks...

 

[Itsalonestar]

Re: How do I support a 7000 lbs. boat?

Best way to support a 25 foot cruiser is get the wife a 2nd job.

What I've done with the sailboat is lower the front end, then stack cinder blocks on each side of the back end and put timbers across under the hull.
Then raise the front end back up, causing the back of the boat to rest on the timbers. Might need some wedge blocking to keep it from rolling back and forth, depending on the hull shape. I then use a come-along to raise the lighter front end suspended from roof of the carport which is steel construction and able to handle the load. You can strategically position the bow under a handy trim limb if nothing else is available. More blocking the better after you pull the trailer out from underneath. That's a heavy boat.

I could imagine a situation where one might lift one end at a time with the other resting on the trailer...might be a pain to get at some of it that way, but I have used things like the 4 foot sanding sticks used on sheetrock for things like that, and also roller extensions for painting in awkward hard to get at places.

If you live near someplace that does sailboat maintenance, they would have the lifts and the expertise to make short work of the project. Might not be a bad idea to call around and get a few quotes before you tear into it. Times are tough, and there might be some idle hands willing to pick up some work. At a minimum, it would give you an idea of how much you're saving by doing it yourself. I love the sweat equity stuff, but some things just aren't worth the hassle.

Ok,

I believe that my main winter project, or more to the point fall project will be to re-finish the bottom of my 25ft cabin cruiser, approx. 7000 lbs.

My question is what is the safest way to remove this boat from the trailer and support it's weight in such a fashion that I can get underneath it and re-finish the hull?

I have some hull blisters, and before I get 9000 different opinions on the "evils" of hull blisters, Keep in mind I have read every piece of literature I can find on the subject, including how to best repair them with glass, epoxy and gelcoat.

I don't need to know about the blisters, just how to safely lift, and hold my boat without spending thousands of dollars to buy / rent, or preferably build my jacks / bunks / supports.

Thanks...