Building an Aligator

[f350ca]

I was surprised on the price Mick, got it from a sawmill near by for 96 cents a board foot. Expected 3 or 4 times that much.

[awemawson]

about £18 per cu foot when I last enquired, and that wasn't first quality

[vtsteam]

Great work, and it's a really interesting project -- especially the overland capability and the strip planking. It's a hauntingly familiar look to me, and brings back great memories from when I built my houseboat 20+ years ago. I lived aboard off and on for nearly ten years. I'm really enjoying your photos and progress.

This is mine under construction in '91:

[vtsteam]

Here it is on launch day -- a cold one in November. If you added sidewheels and a pilot house on top, we'd have practically the same boat!

[f350ca]

Only difference, if we launch here on a cold day in November we'd need ice breaking capabilities.
Neat project, how was it powered?

[vtsteam]

F350ca, I was racing with the winter myself trying to get launched and down the Champlain Canal to the Hudson before the locks closed. Didn't make it, and ended up having it hauled to Portsmouth, VA, launched at a city launching ramp moseyed out past big navy craft and headed south down the Intercoastal.

I wasn't as nicely powered as you will be -- I had a long shaft 25 hp Marner outboard -- got the lowest pitch prop they made for it, and then had it de-pitched at a prop shop. Did hull speed at 2500 rpm. Went 1700 miles with her, across Florida through Okeechobee to the FL west coast and up to Sarasota.

I saw a similar boat to mine in FL that I really admired with twin stern wheels. He could turn on a dime. My outboard motor was useful for maneuverng in a crosswind, too -- but not nearly as effective as his was because he could reverse one wheel. He used a hydraulic motors off of a tractor pump and a tractor engine -- which was also kind of cool.

Will you have sidewheels?

[f350ca]

Yes thats the plan. need to do some research on their design. Have to determine what we'll need for rotational speed and paddle width to reach hull speed. The engine is 5 inch bore and stroke double acting.

[vtsteam]

f350ca, a lot will depend on your displacement. Hull speed will be about 6 knots. The original alligator in the first photo must have been a very heavy displacement boat -- maybe they were carrying ballast. I'm going by how high the sidewheel looks in relation to the hull.

For a boat of our size, dead flat on the bottom and little (or no) rocker you're looking at about 1000 lbs per inch immersion. My boat had almost identical proportions to yours - 8' x 31' -6" and ran 10,000 lbs displacement on about 10" of fairbody draft.

[vtsteam]

Side wheels will make maneuvering very good if you can power them independently and reverse them. Their location forward of other types of wheels is excellent for that.

The pilot house will give some extreme windage, and because of it you'll need that power and turning ability forward, not to be blown off by the wind at slow speed. I had my hands full with an outboard motor and much less windage when we weren't moving fast and it was blowing.

The sidewheels will be a liability, though when trying to tie up at a pier or coming alongside pilings.

[f350ca]

To keep the drive simple, (i.e. I don't have the time build anything too fancy) it will mimic the original and use a simple straight through shaft tying the paddles together. Can't imagine the boat getting used a lot. From my perspective its a fun build a little like building a model only really big. Im sure one trip around the lake and I'll be ready to move on to another project.
Hadn't thought about the paddles when coming along side a dock, would be interesting, we'd planned on beaching it. There are no public wharfs on the lake where we plan to float it.
The ballast on these is in the form of boiler, engine and on the originals a heavy winch with about a mile of cable. We're not planning on the winch so will have to add ballast at the front to compensate for the rear mounted boiler. Still have to come up with a weight on it and the engine. My plan is to use a hydraulic cylinder with a pressure gauge on the port and hang the boiler off the cylinder. The pressure reading times the area should give a weight. Simple but reasonably accurate.