looking for a design

I believe in another thread someone mentioned using a used diesel sourced from a reefer trailer. IIRC they mentioned that these could be had for something like $1000. It may have been in the thread about controllable pitch propellers.

 

Don't know what they use today, but those reefers used to be 4 cylinder Isuzu diesels. I know cause I had a rusted out chevy luv pickup truck, which was a chevy lable on a Isuzu Pup. When the body rusted out, I sold the Isuzu diesel to a fellow that serviced reefer trailers. Got $200

 

There is a recent thread on this forum: "Displacement Speeds - Number if Chines" and the conclusion is that there is little difference at displacement speeds.

As far as a rounded bottom hull and its rolling about, there is an easy solution in the addition of "bilge keels". When I converted a small fiberglass sailboat (an O'Day Javelin) to an inboard electric, I cut out the centerboard well and glassed in a prop shaft, turning a 14 inch propeller. This rounded hull form, now with no centerboard, needed the bilge keels for stability and steering. They were easy to make and install, and they work very well.

One other option you may want to consider: Buy a used centerboard sailboat hull, and convert it to inboard power. These boats often go for a very low price if they have bad sails or a broken mast, and have a good hull shape for displacement speeds. For less than a couple thousand $ you can find these fiberglass cruising sailers, with all the interior comforts, as well as a proven seaworthy hull form. Centerboard sailboats (you don't want a heavy fixed keel hull) in the 25 - 35 foot length are available, although they become scarce in the longer lengths. If you find one to your liking there may be the opportunity to save much money, putting together a displacement power cruiser for a very small fraction of the cost to build a new hull. The next steamboat I put together will use a centerboard fiberglass sailboat hull (19 ft Lightning), which I plan to purchase, with trailer, for under $1000 USD.

 

You bring up an interesting point Yobarnacle. Did the old steamers encounter rough weather? Just curious because if offshore or coastal, there might be a good chop. my understanding is that a flat bottom has stability on the beam or against a beam sea, but not so good in a following sea or into the weather? But im no expert. wouldn't it ride on the surface more, making it a vomit comet? I like the idea of a flat bottom. but Im guessing it would be difficult to build because it would have to have the flat area on the bottom, stiffened much greater than a "v" or a round bilge in order to prevent hogging and sagging stress? I have to emphasise again, I like the idea of steam as a romantic notion, but diesel is a consideration too, maybe better than steam. I think there are pro's and cons to both. Ideally I find it hard to pick one design that does it all. As you probably know- what is it I am willing to live with as far as the tradeoffs?.

 

Thanks Yobarnacle. I know I may sound like I am stonewalling you or others. I promise I am not. I just am very biased to an inboard designs. I grew up with them. I have found them to be the most reliable and efficient. but that's just my opinion.

I have heard of I/O units being used on steam. But im a "Big" prop kind of guy.

I would love to hear what the posters here on my thread own? maybe they could tell me through experience what has worked for them? just a thought.

 

Hi Fred. Surprisingly, I did indeed look into this suggestion just last week in fact.

There is a guy near here who is selling his small marina. he had two boats I was interested in. One was a "v" bottomed Nautaline, 34 ft x 12 beam. the other a Ferro-cement hull.

The "v" hull had some issues. It had lots of room , the interior was in decent shape and I probably could have picked it up in the area of about 2000.00 u.s.

well, some of the doors didn't open properly. So I investigated.

Here was the issue: The keel had been set on a 6 x 6 piece of solid timber about 8 ft long. It(the boat) was not blocked properly, and there was no cradle.
The hull has sat there resting on this timber, and this caused the keel to actually "snake" a little. The timber actually sunk up into the keel itself(it was frp).

If viewed from the profile view you would see the keel start to go up into the hull, and then "bow" down at the bow,(sorry for the double "bow") This caused the boat to drop further down on one side by a few degrees and thus the doors didn't open on the shower stall.
Now the funny thing was, the guy who was selling this boat(for two old people who may or may not exist) told me and I quote" ohh don't worry about the keel, once it is in the water it will pop right back into place, like nothing has happened"

I had to laugh because I highly doubt that after six years of temperature changes etc., that the keel is going to just "pop" back into shape. Maybe Im wrong.??

Its is frp. so Im guessing that bulge in the keel is now permanent and would have to have the whole keel at that area cut out and redone. But that's hazarding a guess.

He insisted it would be ok, then changed his tune a little and asked him to "make him an offer". What's really funny is he is a professional boat builder, he does beautiful round bilge sailboats in old school carvel!.

I later found out he is selling the place.

The second boat he showed me was exactly what you were mentioning. it was an old FC sailboat 39 ft'er. the Fc hull was actually in fair shape and had been done reasonably well for a FC hull.

He wanted to sell it to me for 1 dollar.

My guess is then it becomes my problem and not his. Anyway I went over the hull, tapped it everywhere for voids, and found some holes. Most of the holes could be fixed and in fact the whole hull would have made a nice quasi tugboat style hull because of the plumb stem. but the keel. It was bad, it was leaking and cracked and needed a total rebuild. The bow also had hit a pier on a journey. The bow itself was pushed right in but wasn't noticeable until you looked at it closely , mainly because the previous owners fixed it.

If you looked you could see a huge dent, and you could see where they used a type of epoxy to fix it.
But for 1.00 I considered it.

In the end, I really sensed an urgency in this guys sales tactics. so I passed. It would have been a nightmare to repair the spots in the hull that needed work. The hull to deck was not done properly. and the bow and keel needed a complete redo.

It would be a great idea to find an old sailboat hull, and put a workboat style wheelhouse on it and throw a steam engine in her.

Problem is the weight of that hull, which was 1.5 inches thick at some spots would have called for a large steam engine- Im guessing an Ihp of around 20 hp. and a large boiler, which then needs more fuel etc.
so I passed on both boats.

Last Saturday he had a crane come in to launch the other large vessels that were ashore layed up for the spring. I told him " lift that Nautiline up at the bow and see if that keel "pops" back into position, and if it does, I'd be interested. I never got a call from him...

 

George Beuhler talks about this in his book, in an article called "ode to chines" he states that its not really worth the effort to build a RB or a RC hull over the chined one, that the difference is almost unimportant.
He gives the numbers etc. Its a good article.

 

I'm a big fan of traditional Chinese junks. They sailed all over the world and were flat bottomed.
According to :
G.R.G. Worcester. The Junks and Sampans of the Yangtze. (I own this book)
Shanghai: Order of the Inspector General of Customs, 1947. VM101.W62. exterior photo of details, plate 22, p79. drawing of plan, plate 38. drawing of longitudinal section, plate 38. drawing of cross section, plate 39. exterior photo from river, plate 19, p74.
The turret built junks started off as a plank bottom laid flat on ground and stapled together. Big iron staples.
Bulkheads were erected on this base.
Then a pair of permanent heavy deck girders set longitudinal atop the bulkheads. Using Spanish windlass with these beam girders, the ends of the junk were then winched upwards to final form.
This insured good compression and sealing of the bottom planks to the bulkheads. It also gave the now flexed/tensioned bottom great strength.
Then the sides attached, and the rest of the construction.

I'm showing a cross section, and an edited cross section showing just the turret. The hull. All the rest is superstructure.

I've also posting a youtube url claiming to be traditional Chinese junk construction. The vessel being constructed isn't a junk but a lorcha.
A western style hull with Chinese rig. A design introduced by Europeans in early 1800s.
Western hulls are modeled after fish form. Traditional junk hulls were modeled on the submerged area of a swimming duck. Ducks float, fish submerge.

https://www.youtube.com/watch?v=XZP9fFyitn4