MetalworkingFun Forum

Full Version: Building an Aligator
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Pages: 1 2 3 4 5 6 7 8 9 10 11
Drive the paddles from the half shafts of a vehicles back axle with the engine driving the prop shaft, and use the original brakes on the axle as 'fiddle brakes' for steering.
Had thought about that.
Mortised pockets in the sides for cross timbers and cut the 6x6's to length
[Image: IMG_1332.jpg]
Spent some time at this project today. The guys had done some in my absence.
[Image: IMG_1407.jpg]
The crew has been getting some work done on the boat. The bow and bottom are planked, today we built the skids for the bottom. Left the stern open to get inside to put planks that the skids will through bolt to.

The chap inside the hull is 86 and hard at it, he actually worked on one of these as a deck hand when he was a kid. The chap on top just gave up his medical license at 84. Makes me feel like a kid working with these guys.


[Image: IMG_1461.jpg]
Good stuff Greg,
Nice to see the "young at heart" Thumbsup  Good for them Worthy 
Smiley-eatdrink004 
DaveH
Looks like its coming on well , good to see the old boys getting stuck in Smile , half my mates are in their 80's come to think of it, they all have more things to do than there is hours in the day no time for sitting in rocking chairs Rotfl

 Cheers Mick 
Need to do some actual engineering design work now, and would like some input on paddle size.
My thought is paddle size would be based on the boat sitting stationary and applying steam pressure to the engine to get it moving. Too much paddle area and you won't move the paddle through the water, too small and you won't get enough thrust to move the boat at a reasonable acceleration.
The dia of the paddles will be 8 feet. That gets the shaft at deck level and the bottom of the paddles even with the bottom of the boat.
Rotational speed would be set to give hull speed plus a certain amount for slip. How much slip?
Once the speed is determined I can calculate the torque available at the paddle shaft based on the bore and stoke of the steam engine and boiler pressure.
So for a given torque and a 4 foot arm how do I determine how much area on the blades can be moved through still water at startup?

Any thoughts would be appreciated, there's not much in the way of engineering formulas out there on the net for paddle wheelers, wonder why?
The basic hull is finished. The rest of the crew (I don't paint) brushed on a coat of some aluminum rich urethane for an undercoat then a rubberized top coat. Was slow drying in the shed so we pulled it out yesterday. Used log rollers under it and the tractor to hold up the front as we pulled. Worked quite well. Going to let the rubber cure for a few days then flip it over to start the machinery install. 
[Image: IMG_1739.jpg]

By the volumes of wood it should weigh about 4000 pounds right now.
With the rubberized top coat wont the champagne bottle bounce off instead of smashing?
Pages: 1 2 3 4 5 6 7 8 9 10 11