Boat Hoist Runner/bunk question

[Smackledorf]

Wasn't sure which forum to throw this in.

I just had a boat well and hoist installed. I bought a 2001 240 sea ray sundeck in the fall and it is still in storage. They finally completed the last bit of work on the hoist today. The problem is my runners/bunks/whatever are adjustable and I need to know how to set them up so they are ready when I pick the boat up. The boat is an hour away and I'd rather have things prepped and ready before I drive the boat back to my house.

My bunks are 16 inches high but are mounted on an I-beam. It is just a simple set up with two straight running boards to support the boat. Obviously I don't want to be dragging the underside of the boat on the I-beam. Given that the boat has chines and what-not, I feel it could be a mistake to simply bust out the geometry using the deadrise. On top of that, while my canal is pretty calm, I would also want to account for any forward pitching while driving onto the lift I would think.

Any advice from other people who have set this up before I do something silly and wreck my new toy?

 

[Smackledorf]

Oh, and if I do simply knockout the geometry, then if I wanted 2 extra inches of space with the boat at rest I come up with 14 divided by tan21 (21 is the deadrise) and see that I can have my bunks 70 inches apart. I'm thinking I'd want at least 5 inches there to account for pitch or wake while getting on the hoist.

But again, I'm pretty loathe to pretend the boat hull is the right fit for a triangle. I'm sure someone out there has some trailering or hoist experience in this regard.


Follow-up question: My bunks leave the boat resting on the corner of the board. My marine company says this is no problem, and pointed out that this is exactly the setup my boat is resting on at the marina all winter. How beneficial would it be to modify the bunks down the line so the hull rests on the flat of an angled board? My hoist's bracketed setup allows for plenty of adjustment and board changing options without too much effort.

 

[Blueone]

I can get you some dimensions tonight off of my lift. I had it setup for a 2003 Sundeck, should be same hull

 

[Bucit]

70 inches apart? My 280 sits on a lift and since I have thru-hulls and such my bunks are like 19-21"s apart. This is the only spot where I miss everything and don't sit on the Chines.

 

[tdgard]

70" sounds way too wide to me. I would have to measure the next time I'm at the boat, but mine are around 36". It sits between the second set of chines and I still think it's too wide. At 70" I doubt you will get the drive out of the water. I barely do depending how much fuel and water I have on board.

 

[tdgard]

Also my bunks are angled to the hull.

 

[blaster]

Is the boat in rack storage now? If so, measure the distance between the bunks on the rack. Or if you see a like boat on a trailer, same thing. Just be sure to account for tabs, transducers, clamshells, etc. Dont want to rest on those. Make sure the boat doesn't hang off the bunks unsupported. Its OK if the bunks stick out a little, but not the other way around.

 

[Blueone]

Here is my setup

 

[Smackledorf]

70 inches apart? My 280 sits on a lift and since I have thru-hulls and such my bunks are like 19-21"s apart. This is the only spot where I miss everything and don't sit on the Chines.

That was just an example of where the math would land me for given "gaps" between keel and ibeam. I wasn't planning on going with a 2" gap

 

[sibnai1]

Sine, Cosine, Tangent - Oh Hell Another Hour Of Arithmetic ......................... Holy flashback, who knew I'd see this resurface on a boating forum??? lol

 

[Smackledorf]

Is the boat in rack storage now? If so, measure the distance between the bunks on the rack. Or if you see a like boat on a trailer, same thing. Just be sure to account for tabs, transducers, clamshells, etc. Dont want to rest on those. Make sure the boat doesn't hang off the bunks unsupported. Its OK if the bunks stick out a little, but not the other way around.

How bad is it if the boat does hang off the edge a bit? Unfortunately, with mine pulled almost all the way to the seawall in the front I still have a foot hanging off the back of the bunk. Is that really doing to be a problem such that I should go out and buy some lumber to lengthen the bunks?

Also, regarding the chine, what is so bad about sitting on it? I understand with a much larger boat that overall hull design doesn't lend itself to two long bunks because of the curvature of the hull and its chines, but my chines are as straight as any other part of the hull. Fwiw, I have seen boats in rack storage put on chines, and fork lifts that pull boats out for rack and launch grab chine all the time. I don't intend this as an argument mind you; I just have a boatload to learn about fiberglass boats. I've been a pontooner and aluminum guy in the past and those things are just indestructible beasts, not to mention cheap enough that I never really concerned myself with giving them a beating.

I do appreciate all of your time in this.

 

[blaster]

I am no expert on this by any means. The bad thing about not fully supporting the stern is that most of the weight is there. Not properly supported the back end can sag and deform over time. If you put the bunks under the chines it would be difficult to raise the boat high enough out of the water.

Perhaps someone more knowledgeable will chime in with more details.