Hull support trestle

[Tafflad]

Would like to support boat to take it off the trailer.
I have 2 professional hull support support stands, so would us those on flat ‘pod’ areas either side of transom .. obviously due to engine also the heaviest.

Thinking of making a wooden support trestle to match vee of hull above 1/3 from bow.
anybody made such a trestle, have seen them in boat yards when they are laying up hills.

Just looking for a design, to ensure I built strong enough, but as little as possible.

 

[Chris1956]

What kind, length of boat? Normally boats are blocked up at the transom corners, and under the bow keel. Cement blocks with wood on their tops works real well.

 

[gm280]

Depending on your boat/hull design, that can be anything from a few support areas to an entire cradle design. Anything that can support the boat is workable. I've seen some people use old tires or block foam to support their boats. But without pictures, that is about all I can offer. Post a picture or three for us to see what you are dealing with. Probably get much better answers...

 

[Tafflad]

Picture of boat as requested .. overall 21' ..... hull length 19'
I want to jack rear up onto stands then get trailer out from underneath ... appreciate a bit of shuffling will be needed due to trailer axles.

 

[Tafflad]

Years ago I rolled trailer off the back onto a stack of large 4x4 tyres ... but this is a heavier boat.

 

[JASinIL2006]

I built a trestle out of 2x4s using 1/4" carriage bolts. I first found the correct angle for the 'V' that supported the keel and sides of the hull, then I cut legs and a base to hold the boat just a bit higher than the trailer bunks. My trestle had three legs (on in the middle, and one on each end) to support the weight of the boat. I used some very thick, dense foam between the trestle and the hull to help distribute the load and to conform to the sides of the hull. It was very stable.

I used pneumatic jacks with wood blocks to lift the bow, then slid the trestle underneath. I then jacked up the stern, moved the trailer back a bit, re-positioned the stern jacks, moved the trailer again, and so on.

After getting the trailer out from under it, I replaced the stern jacks with jackstands with wood blocking (to distribute the load). The boat was supported at three points: the two stern jackstands and the trestle by the bow. It was extremely stable.

 

[gm280]

Think abut this. Since the boat sits on the trailer and is supported via the bunks and such, mimic that same design off the trailer and it has to work. Not an Earth Shattering idea, mimic what you already have with the trailer supports and remove it to those supports. JMHO

 

[Chris1956]

Gee, easy stuff. lower tongue of trailer as much as possible. Put stacks of cement blocks under each transom corner. Top them with wood so that they touch hull. You want at least 12"X4" wood contact area with hull, including right under transom. use double blocks on first and second course of block for stability.

Now lift trailer tongue until rear of boat is off trailer. Stack cement blocks under keel an top with wood, to touch the hull. Now lower tongue a few inches, and boat will be off trailer an inch or so.

You can now repair trailer, bottom paint boat or other things. Pulling trailer out requires a bottle jack and a vee block of wood, and you need to reblock the keel as you pass the side trailer supports.

 

[Tafflad]

It’s pulling trailer out, I want to coat it all with Lanoguard.
is there any reason not to use the screw Jack bolt stands I have on rear ? These are rated 5 Ton .... the tops are around 12” x 8” hard rubber support pads on heavy duty Cast swivels, onto 2” acme thread bars into triangular bases.
I have bottle or trolley Jack I can use with wooden Vee blocks on the front



stands are similar to those in pic ..

 

[Tafflad]

Think abut this. Since the boat sits on the trailer and is supported via the bunks and such, mimic that same design off the trailer and it has to work. Not an Earth Shattering idea, mimic what you already have with the trailer supports and remove it to those supports. JMHO

The issue is the boat is supported over its length by rollers so multi-point support over ab 12’. So not easy to mimic that .... hence my thoughts on 2x heavy duty stands at transom, where the weight is ....and wooden blocks matching Vee on a wooden trestle on bow.

 

[Chris1956]

Take a ride to any marina that stores boats on land. You will see stands like you have used, as well as cement blocks. Notice where they place the blocks on multiple types and sizes of boats.

I cannot comment on stands as I have never used them.

Never support the boat on a jack, and crawl under it. Also, before pulling the trailer out, grab the boat at the side of the transom and wiggle it. it should not move no matter how hard you push. Ditto for the blocks under the bow.

 

[briangcc]

Years, and years ago....think late 80's here.... the '56 MFG had a trailer issue that the marina caused (Long story). Their solution was to lower the tongue all the way to the ground, stuff a couple of those stands under the transom, jack the bow up and support it like you're suggesting with cribbing. It stayed there no issue while they figured out what to do with the matching vintage TeeNee trailer.

Now, being much wiser and more safety conscious, IF I was doing that today I think I'd link the stands together with some sort of strapping (and make sure they have very wide bases so they aren't tippy) so they couldn't get pushed out from under the boat OR I'd just use some cribbing under the transom too to support it.

**Disclaimer...I've seen the carnage left when the jacks like what you're thinking of using slip out from under a boat...weren't pretty.

 

[JASinIL2006]

Never support the boat on a jack, and crawl under it. Also, before pulling the trailer out, grab the boat at the side of the transom and wiggle it. it should not move no matter how hard you push. Ditto for the blocks under the bow.

This is really good advice regardless of the type of vehicle. Never get under anything that isn't supported by something that can't move; use a jackstand, not a jack to support the boat. A jack is only good for getting the thing up in the air; you need something more stable to hold it there.