Marine Railway System - V bunks? Long Bunks? Slings? overhang?

[rjd75]

So I just sold my 18ft boat and moved up to a 20ft Crownline. It's about 1000lbs heavier than my old boat. The marine rail system I use is rated for 4000lbs and it is able to pull it up the track. The concern I have is the type of cart I have on the rail. I did some research about how much overhang is ok at the transom and came across all kinds of posts about putting a hook in your hull if you have an overhang. For the record my 18 footer sat on this cart for 13 years including winter storage and I didn't notice any difference or problem with the hull. But now with the new heavier boat I want to make sure it is supported properly. The problem is that with the current v bunks you have to have some overhang, becuase if you have it too far forward you risk the boat being pulled out resting on the outdrive in rough water. I always thought it was ok to have some overhang because the motor is being supported and since it's an i/o most of the weight is in the block not the outdrive. Regardless I am comtemplating change to two long bunks running front to back pretty much the same as a trailer. The other option that is used around here is a cart that has two yolks with slings, it is definitely more gentle pulling the boat out, but not sure I like the idea of the boat sitting in slings for most of its life and the sling still needs to be forward of the transom as well. Here are some pics to give you a better idea of what I am talking about..

The first lift is the type I have with the v bunks.. Notice how the boat sits with the transom overhanging. That is my current setup.



The second is what I am considering doing, removing the vbunks and running some 2x6s or 2x8s either upright or flat using trailer bunk attachments.




The third is another system that is commonly used on my lake. Altough no one makes them anymore. I don't know if it is because the cart is to difficult to transport and everything these days needs to be modular, or whether the industry has moved away from slings for a reason. My neighbor has the sling setup and loves it and says I should do it but I have my reservations for the reasons noted above.



Welcoming opinions on what I should do..

 

[crabby captain john]

Re: Marine Railway System - V bunks? Long Bunks? Slings? overhang?

I like #2 the best! Slings-- not at all!

 

[scoutabout]

Re: Marine Railway System - V bunks? Long Bunks? Slings? overhang?

I've got the cross bunks (although hard to see in this pic). I worry about overhang too and try to limit it as much as possible. Can't completely avoid it though but have seen no evidence of hull problems in five years of Monday to Friday, May to Oct use.

I do think the front to back bunks are the way to go if you can do it.



By the way, do you have trouble keeping your track joints level? The shifting sand means they go out of alignment constantly and the carriage gets hung up on the raised lip. Looking for some kind of flexible material to bridge the gap because resetting the height of every piece three times a summer is a major drag. I regret getting the thing at all - shoulda done a lift...

Sorry to hijack!

 

[Silverbullet555]

Re: Marine Railway System - V bunks? Long Bunks? Slings? overhang?

The sling really doesn't look like a sling. It looks like the boat rests on the keel on the rack and the sling just holds it upright. That being said, I would not be a fan of that. I would find a way to set up bunks like a trailer and go from there.

 

[rjd75]

Re: Marine Railway System - V bunks? Long Bunks? Slings? overhang?

I've got the cross bunks (although hard to see in this pic). I worry about overhang too and try to limit it as much as possible. Can't completely avoid it though but have seen no evidence of hull problems in five years of Monday to Friday, May to Oct use.

I do think the front to back bunks are the way to go if you can do it.

By the way, do you have trouble keeping your track joints level? The shifting sand means they go out of alignment constantly and the carriage gets hung up on the raised lip. Looking for some kind of flexible material to bridge the gap because resetting the height of every piece three times a summer is a major drag. I regret getting the thing at all - shoulda done a lift...

Sorry to hijack!

Looks like we have the same rail the "Naylor". There are thousands of these in ontario and I find it hard to believe that the slight bit of overhang would cause problems to all of these boats. Especially with I/O boats, I would be more concerned about your big outboard! I know what you mean about the joints, I have a big sledge hammer I use to pound them out. It's usually only a problem when I first put it in, I have a rock bottom so it stays firm after the initial install. My plan is to remove the V's and buy some bunk supports and put bunks down the length of the cart. There are no cross braces either though, so the bunks would be spanning about 7 ft, but I don't see it as an issue because with the Vs there are only two points on the keel where the boat is being supported.

The sling really doesn't look like a sling. It looks like the boat rests on the keel on the rack and the sling just holds it upright. That being said, I would not be a fan of that. I would find a way to set up bunks like a trailer and go from there.

It appears that way but when you wrap the sling around an 8ft wide boat it raises itself a few inches off the bottom and elevates the boat. I don't think the pressure is as great as a sling that wraps around the sides which is why some believe this is the most gentle way to pick up the boat.