Building a boat in a rotisserie

[Dale R. Hamilton]

So the car resto guys use these big steel frames with a pivot point on each end to raise/lower a whole car. They can easily rotate the whole thing to work on the bottom. I'm thinking these would be dandy for building a boat less than 20 feet long. Besides being able to rotate it- to work inside the hull, or on the bottom, or have any side panel on a level surface- the rotisserie would also serve as a steel frame to enclose your wooden jig. This should make the whole thing much more regid. They sell for $1200 delux version, powder coated, all the accessories, or I can buy a basic used one for $500. Whatdaya tink?

[John E Hardiman]

Common in the fiberglass boatbuilding industry.

[paladin]

Yes...but make sure it's rigid enough for a heavy truck...flex dunno mean nothing in the auto because the chassis etc will flex enough and not bend or break.....a 1/16th inch sag when your building the boat may cause a permanent built in twist to one side...

[Cuyahoga Chuck]

Wooden boats are built on a solid base for one very important reason. If the boat comes out crooked it will want to to do strange things like trying to go in a circle. Straightness and conformity (having one side the mirror image of the other) are very important and trying to back up and correct an error is rather difficult.
A car with a frame supplies it's own backbone. Wooden boats are made from a lot of small pieces which don't have any integrety until the hull is finished.
They do build some strip-built kayaks on an inner strongback that allows turning the hull on it axis. But, these boats are, generally, 55 lb or less and have an egg-shell type of construction where all the strength and stiffness is in the skin.

[Dale R. Hamilton]

well guys I'm proposing to use the rotisserie to hold and support the building jig- as opposed to just letting the shop floor support the jig. Seems to me a steel frame would add additional regidity.

[shadow99]

If the vessel is light enough it works great for painting. I used the combination of two engine rebuilding stands, with a steel brace inbetween them, to paint (bottom & sides), then flip and varnish (topside deck) on my 140lb modified Swifty 12.

Both my engine stands are the (T-style), with a faceplate and arms to attach the engine. Make'm sturdy first, add extensions.
I extended the width of each stand, plus 6" to the width of the boat (70" total width on my stands), then I attached a 2x2 piece of steel betweeen them mounted to there front legs (I used axle U bolts to attach and have adjustment), the length of of boat overall plus a few inches for play.
A few 2x6 boards were used to attach at the transom using clamps, one of the 2x6 boards was bolted with carriage bolts to the faceplate on the engine stand. Another 2x6 ran the length of the boat, supports were fashioned at the front thwart, mast step, and bowsprint, a chunk of 90' angle iron attached 2x6 to front engine stand. It sure beats flipping boat over alone.

Rick

[Tom Robb]

Sounds handy for series mass production. A bit of overkill for a one-off?
On wheels so you can move it about; built in hydraulic jacks to raise and lower to handy heights - expensive, but sweet.

[Dave Gray]

I remember seeing an article in WB or a posting here (I disrecollect) where someone used an I-beam structure as a backbone and did exactly what you are proposing - he could lean the hull one way or the other. It was rather cool and it was a wooden boat. I would have to rattle this noggin for a while to remember where I saw it, or look through back issues when I get home.

[Sal's Dad]

Like this Atkin? (nice shiny wood :eek: )

http://f9g.yahoofs.com/groups/g_11779707/cf3a/__sr_/394f.jpg?grI_9yFBw_ErKikw

http://f9g.yahoofs.com/groups/g_11779707/cf3a/__sr_/a5b8.jpg?grwO.yFBi0iywdhI

http://f9g.yahoofs.com/groups/g_11779707/cf3a/__sr_/eb26.jpg?grwO.yFBXqqCrtp_

http://f7.yahoofs.com/users/3FepGddtODnF/__sr_/7aa3.jpg?tkn=phQiKzFBn0gLoiHS&saveas=RM+Stern+shape+2


Alex Hadden rotated 34' Noble Cab this way, a few years back...

Sal's Dad

(why do I have such a hard time posting photos?)

[Ethan]

Let me tell you...the hands down, absolute best $1000 I ever spent for tools was for 2 used rolling gantries. I think I paid something around $800 for the pair and another $250 or so to have them sandblasted and painted. Makes loading/unloading trailers, moving large items around the shop, and flipping boats easy to do by myself. Plus, when not in use, they quasi-nest and push up against the wall. Might be something worth looking into if you're interested in single person material handling.

There's nothing overly complicated about their construction - I don't see why anybody with some welding skills couldn't gin a pair up for relatively cheap.

[WillW]

Boyles, that kind of overhead frame is exactly what I've been looking for, as a way to raise a boat that's on a cradle and lower it onto a trailer. A little heavier though -- 2 tons.

[Dale R. Hamilton]

Lads- the only problem with the gantry crane idea is that you can't lock the load at any point on its turning arc. It is very nice to always have a horizontal surface to work on and spread your goop. Also, the cranes don't provide the brace for your jig.

I don't really have a prob lifting weight. I bought a 4000 lb forklift named Sherman a few years back and he has been really handy lifting engine blocks off trucks and such.

[paladin]

if'n you're gonna build the boat in a rotisserythingy, dunno forget the oven needs the proper heat and ventilation.....a few heat lamps will work well....after finishing the basic carcass ya wanna baste it, I suggest a light sauce consisting of Xynole and M.A.S. epoxy.....allow to soak in it's own juices for three-four days, judiciously clean the skin, wipe carefully with a tack cloth, apply primer and then finish....when finished...buy pig...install pig in rotisseriethingy, use heat lamps to cook slowly for a day or so....collect fresh bath water for all concerned (I hear Heinekens is a good brand) invite neighbors over to assist removing pig from rotisserie.....and a few forumites....:D

[Figment]

Ding Ding, paging Mike Keers.
Mike Keers, please locate the nearest courtesy-computer and chime in on the boat-rotissierie thread.

[John Meachen]

One thing that hasn't been mentioned is that it can be very useful to have a means of locking the part bult boat in a horizontal position.This means using more than just a locking pin.The boat needs to be precisely level for jobs such as fitting a centreboard case or marking a water line.If this can be achieved,the plan proposed could work very well.

[Ethan]

Boyles, that kind of overhead frame is exactly what I've been looking for, as a way to raise a boat that's on a cradle and lower it onto a trailer. A little heavier though -- 2 tons.

That would be a gantry, Will. One of mine has a 2000# capacity and the other has a 4000# capacity - you can get the shop size in up to 10,000# (I think), but the bigger, the pricier! Basically they're just uprights with bracing and an I-beam for the 12' span.

I'm not sure I agree on the inability to stop a hull mid turn. With the 12' span, it's not difficult to rig a cross line to accomplish that feat - the weight of the gantry plus the moment arm of the opposite end worked just fine when we flipped a 4000# tractor (don't ask!:rolleyes:). As for steadying and leveling to do work while it's suspended, I think you're right, I can't think of a method that would work to satisfaction.

:D Chuck, anything for free beer, eh?

[Tylerdurden]

If you are building in metal the ability to rotate would be useful.
I am lame at wood in comparison so I refuse to take any chances.
I thought about converting a couple of engine stands to do a steel
project years ago but after doing the framing I thought better of it and pressed on in the conventional manner.

[Sal's Dad]

To "lock" the boat into position, I just lowered it onto blocks, or the ground. When it was raised up to "rotate" position, it was above comfortable working height.

[Tom Robb]

Rotating anything rather large will become a challange/inconvenient if seriously unbalanced won't it?