I'd be concerned with the strap chafing Ron. I'd feel a bit more comfortable adding a piece of black plastic sewer pipe, cut down the middle, to go between the straps and tubes. Surely there is a ready made product?
Actually, Chaffing was not even on my worry list, but now I can add that! Thanks!
My biggest concern is stress on the Toon (Tube). A wooden cradle, like on a trailer, doesn't really provide ultimate support since wood is flexible. The Toon support is concentrated at the bunk supports and diminishes in the area between the supports.
I can actually see this lack of support on my trailer bunks.
This means the Toons are not continuously supported and only supported in a few spots.
You can see, I'm trying to convince myself that straps are sufficient support.
Then there is this guy...This is exaggerated but demonstrates a problem with bunks. This makes me queasy. All the pressure is on his lifting strake.
This guy says "Everyone at his lake" just puts a 2x6 under the Toon.
This got me thinking...That Keel on the bottom would be putting pressure on the Toon with this lifting method but at the same time, that keel could give support to the Toon if I were just using a strap. It would be like a built in mini bunk.
One option I was thinking about is to modify my existing cradle to work for a pontoon.
The cross beams can't be used because they are shaped like a "V" for a boat and a pontoon lift is normally flat.
From the bottom of the "V" to the top of the bunk is 16". Too big for my situation. That's one of the good things about a strap is they are very thin and when the lake level is down (Mostly in the winter) they are not a factor, whereas, I couldn't get my ski boat out of the boathouse in the winter because of how tall the cradle is.
The cables attach on the side rails of my boat cradle. The side rail is a straight (flat) piece of aluminum "I" beam.
I could take the side rails off and turn them 90 degrees and then run the bunk across them like this.
Or, I could go out there and rip that cradle out of there and install the straps I already have and be done with it. There are over 50 pontoons lifted this way right down the road from me. Can they all be wrong?