Boat launch/recovery frame

[Luke]

This project probably started around 3 years ago, in terms of the thinking and the initial drawings, however, it was just under a year ago that I took delivery of a load of 60 x 60 x 4 SHS, some cut to length UB and UC, and just over 400 laser cuts parts.




Most of the brackets were made from flat parts welded together. It took a couple of weekends to jig them up, tack them, then store them ready for final assembly and welding. If I did anything like this again, I'd get the supplier to bend them for me. I didn't realise how long it would take.





Once the brackets were ready, some proper assembly and welding could begin.

 

[Luke]

Overall, the frame weighs about 1100 Kg, but everything is designed so that it can be lifted and carried by a person, or maybe two, for the long UB lengths.

It was less repetitious once all the brackets and sub-assemblies had been finished. At least then, it looked a bit more like progress.

 

[slim_boy_fat]

Like a HUGE jigsaw puzzle.

 

[Luke]

All of the parts were loaded up in to a van and taken down to my dads, for the first trial assembly.



We used the crane for the test run. This was the first time we'd been able to check the tolerances we were dealing with - around 50 mm between the boat and the frame, and the frame and the trailer.



Success! The frame was then disassembled and taken down to the boat yard.



And reassembled, ready for recovery.



The frame is picked up by and open-ended trailer, with two beams that lift hydraulically. There's a small pump and battery on the front of the trailer.

The frame is positioned at low water, then we put the boat in on the next morning's high water. Then, when the tide goes out again, we picked the boat up and pulled it back to the car park.

 

[Luke]

The trailer has been around for about 30 years, in one form or another, and is rated for 7.5 te. The frame is around 1100 Kg and the boat is just over 6 te, so we're at the limit of the trailer in terms of both weight and width. Most of the other frame have at least 200 mm clearance side to side. We have around 50 mm.

The guy who drives the tractor is very good at it. The tractor's front wheels work very hard to make adjustments to the trailer's steering wheels. Lock to lock on the tractor in the space of a few feet provides very fine adjustments at the trailer. Despite the low margin for error, he got the trailer around the frame with only one or two corrections, most times.

 

[Luke]

About an hour after high water;





The frame has two outriggers to stop it moving towards the next slipway, either during the tide-and-a-half between putting it down and putting the boat in, or whilst putting the boat in.

Frames moving is a common problem, it means that the trailer can't get around the trailer to pick it and the boat up. Sometimes the trailer can pull the frame with a chain, which isn't good, sometimes the boat has to be floated off and everything has to be reset.



The chains pass through the other slip way and have box section shackled to the other end.



The outriggers are in two parts, so that they can be released when/if the frame sits up against the other slipway.

 

[500e]

A lot of thought, nice ideas, does it go under cover for the winter ?,

 

[Luke]

The frame will live outside. It will get galvanised when it hasn't got the boat in it.

The boat has/had a cover, but it is pretty worn. The guide posts on the frame look like they can be used to put a cover over at least some of the boat.

 

[addjunkie]

Lots of thinking, has gone into that. Couple of arches on those up rights and the boat is undercover.

Are the fin keeled boats done the same way or craned into the cradles?

 

[Luke]

The fin keelers have a slightly easier time getting in to their frames, which are simpler. The other boats are smaller as well, so they don't have to overhang the sides of the trailer in the same way. The frames are quite a bit narrower - 200 mm or so less than trailer width.

They're much more concerned about falling over though. They have to adjust as they dry out to make sure they're upright by the point they can get to the hull supports to wind them in.

 

[addjunkie]

The fin keelers have a slightly easier time getting in to their frames, which are simpler. The other boats are smaller as well, so they don't have to overhang the sides of the trailer in the same way. The frames are quite a bit narrower - 200 mm or so less than trailer width.

They're much more concerned about falling over though. They have to adjust as they dry out to make sure they're upright by the point they can get to the hull supports to wind them in.

View attachment 160714
View attachment 160715

Thats the kind of cradle set up Im more familiar with. It was this picture that made me ask, as there is no route for the keel to slide through the cradle. And if the water deep enough for the keel to pass over the steel, the boat would be very vulnerable waiting for the tide to drop. Travel hoists, make life so much more simple, turn up drive in, up and out, on a cradle, in about 20 minutes.

 

[Luke]

We're not sure how he does it. It looks like he has a lifting keel, which would give him minimal draft as he comes in to the frame. Also, its made from aluminium and bolted, which is different from all the standard frames.

Yup, either a travelling hoist or a crane are definitely easier. They're also around x6 the annual haul out and launch cost. Our frame will have paid for itself in about 5 years, going on material costs. I don't want to work it out with labour included....

 

[500e]

The Dufour 38 lifts out on strops & spreaders fin keel, 6Ft 3Inches draught we store in a purpose built frame

 

[addjunkie]

The Dufour 38 lifts out on strops & spreaders fin keel, 6Ft 3Inches draught we store in a purpose built frame

Nice boat, thats my experience with keel boats too, or a travel hoist.