Designing a boat at age 12

[confused]

ok, ok! I just stick with this one boat I designed yesterday, it is 8ft long, 4 ft wide, and the hull is 1.5ft in height. cheaper anyway. and it should be stable considering the length to width ratio. I do not need any of your help for that, it is so simple to build. I just use the weedeater engine in the garage (if a 1.5 hp engine can push a 13 footer, why not an 8 footer?) and buy a cheapo composite prop online. I can build it ALL myself, (wouldn't be surprised if a 5 year old could) and I even fix the engine myself! I have engine expirence! I'll even attach the prop to the engine by MYSELF. and I didn't really want you to machine it forme anyway.

[marshmat]

Hi "confused",

I'll add a few of my own thoughts to the matter too. Feel free to disagree.

If I recall correctly, you said you were 13? Well, I was only two years older than that when I built my Bolger "Diablo", and it worked out pretty well, so yes, I do think you can do it.

Now, I'm curious what exactly draws you to the steam engine? Yes, it's a romantic notion, and yes, they do draw an admiring crowd. But most of the space is taken up by the boiler and engine, and what's left is full of coal, with a couple of burly guys to shovel it into the boiler as fast as they can. The "TinyPower" engines, like most of their kind, are bulky and expensive (although not expensive enough to be good). Steamboats are a nice romantic notion, but they are expensive, hard to build, and substantially more dangerous than normal motors. (I have seen a couple of small 50-100 psi pressure vessels blow- it is very, very scary and everyone is deaf for an hour afterwards. A steamboat boiler operates at similar or higher pressures, and is scalding hot to boot.)

A small, lightweight hull with a weedwhacker for power could be a really fun, quick and inexpensive project to get you started. Once you've been out on the water for a couple of seasons you start to get a feel for what type of boat might be best suited to the things you find you like to do out there. One of the nice things about an 8 to 12 footer with a cheap, compact engine is that you can easily flip it up on top of the car to get to all sorts of neat places. I might suggest going a little more towards the long side of that range- closer to 12 feet than to 8- so that you have enough room to carry a couple of friends. An 8-footer is great for poking into quiet streams where the fish are, but tends to get a bit cramped with more than one or two people. A weedwhacker won't be enough power to get on plane, but in a hull designed for efficient low-speed running it might work very well. Such a hull would likely also row very nicely.

I know some of the guys can get a bit on edge around here when discussions heat up. Don't let it get to you. The amount of expertise on this board is really, really high, even if it's not always what you want to hear. (I wish this community had been around when I built Sunset Chaser- the advice of some of the builders on here could have saved me an awful lot of time and a fair amount of wasted materials.)

[apex1]

Originally Posted by marshmat

The "TinyPower" engines, like most of their kind, are bulky and expensive (although not expensive enough to be good).

Matt .................10 points! For all your post, but especially for the statement above!
A real good engineered and built steam installation of 2 to 10 hp (there is not a big difference) is about 18.000€ to 25.000€ !
Anyway I would´nt discourage a young man to build a steam launch (after he´s earned some knowledge),it CAN be very safe and nice.
Did you notice the vessel I recommended to start with?

confused
I think I have to remove some doubts that I do´nt believe you are able to build your boat! I´m sure you are. Only for that reason I did the effort to give you a leading hand! I regret to destroy some of your imaginations, but hope I could replace them by more achievable tasks.
If I was a bit frank or harsh, stand it. I´m much much ruder with the adults.
And bear in mind please I am a German, this is not my mothers tongue.
Regards
Richard

[confused]

ok. maybe I start with steam engines 10 years from now, and stick with gas and diesel for now until then. Maybe just gas, diesels kinda expensive. I like steam engines because gas and diesel suck, and steam engines can burn anything, long as it's flamable. And they have lot's of torque, (I knew that before apex told me). My original idea was to use a hot bulb engine, but they seemed to have become extinct.

[confused]

If you have any sites where I can buy a hot bulb engine, then please tell.

[apex1]

Originally Posted by confused

If you have any sites where I can buy a hot bulb engine, then please tell.

Yes you knew the high torque fact already and mentioned it in a earlier post.

No, there will hardly be a hotbulb engine available, except you are near an old fishertown and can find a example of the old "SABB" engines, very popular till the late 50 ies. But such a monster has a weight of some 800 or 1000 lbs.
There have been thousands of tractors around with such engines, but I think they are almost all in collectors hands today and so, spare engines will be precious and rare.
Still nice to see that you are looking for something different!
Regards
Richard

[marshmat]

You'd be amazed what a beat-up old American gas engine can burn.... I know a guy who ran out of gas on the way into the lake once, so he poured a can of Coleman stove naptha into the tank of his Chevy and kept on going. The truck didn't care. My '94 Johnson 30 can reportedly burn 67-octane (I didn't know they made gas that crappy).

If you're into radical fuels, a solid old diesel without too much computerization ought to be able to burn a decent variety of fuels (including the crud drained from a McDonald's deep fryer) with a bit of tweaking.

I'm glad to see you're looking for something different, too Most folks just slap on whatever outboard happens to be popular in their area, and off they go. Then when it breaks, out comes the wallet. Doing it yourself is much more fun!

As far as engines go, "confused", something you may find interesting would be to look up a local dealer in used/refurbished reefer trucks. Some of the refrigeration units use little diesel engines that, now and then, can be had cheap and in need of a bit of work. Still, for your first build, I think the weedwhacker engine would be an ideal choice- simple, cheap, light, easy to fix with tools you're likely to have access to, and it'll get you on the water so you can get a feel for what kind of boating you like best.

[confused]

Cool! I found a site that sells diesels that might be able to burn wvo! (Waste Vegatable Oil) Actually I found it about a month ago, I'm just telling you. of course the engines would be to heavy for an 8 footer. I e-mailed them awhile ago about their 3.5 hp engine, but they haven't gotten back with me yet. I'll give you the site if you want to use one of these engines on one of your boats. http://www.prakash-india.com/product/de_ac_3.5to10.htm I am going to e-mail those buttwipes again and see if they get back with me finally!

[apex1]

Originally Posted by confused

Cool! I found a site that sells diesels that might be able to burn wvo! (Waste Vegatable Oil) Actually I found it about a month ago, I'm just telling you. of course the engines would be to heavy for an 8 footer. I e-mailed them awhile ago about their 3.5 hp engine, but they haven't gotten back with me yet. I'll give you the site if you want to use one of these engines on one of your boats. http://www.prakash-india.com/product/de_ac_3.5to10.htm I am going to e-mail those buttwipes again and see if they get back with me finally!

Yaahhhh..these old (usually English) beasts burn almost every liquid (except catpinkle, but I´m not shure about that).

The most popular of this type in your country are old "Lister Diesels" and their derivates and copies. look:
http://www.listeroid.com/engines.html
They sell for about $ 1500 to 2000 (at your backdoor) and have a weight from 800 lbs up.
Wear a knights armour to operate such copy, some tend to disintegrate suddenly!
To prakash.... I do´nt recommend to call a future business partner buttwipe.
Maybe they did´nt take your approach for serious? Usually the established companies in India are very polite and helpful.

Regards
Richard

[confused]

yah, I've been to that site before. I watched a video on youtube of one of those running. I'll give you the link for the video if you want to watch it. http://www.youtube.com/watch?v=fUF2X...eature=related I just asked those Injuns to send a price on the 3.5 hp air cooled engine, which looked like the cheapest, and the (lightest ). On the specs. the weight said 80, I'm not sure if they mean pounds or tons

[confused]

Uhhhh... sorry for kinda ruining your thread starling...(snicker)

[marshmat]

The Prakash you're looking at is most likely 80 kg, or about 180 lb. To that, you'll need to add the weight and cost of mounts, gearbox, shaft, etc. Don't forget to add the cost of shipping it halfway around the world, which can be significant. (Not trying to discourage you, just alerting you to some of the hidden and problematic numbers that often don't crop up until too late in the process.) These look like very "old tech" engines, based on designs that might date back to the '50s or earlier, so probably a bit smoky as well as being fairly heavy for the power output. It's awfully hard to evaluate the build quality from an online spec sheet though. If there's a good machinist putting them together, you may end up with something that'll burn any fuel you can find and will live for 40 years. On the other hand, there's always the possibility of getting a lemon.

[confused]

1 kilogram = 2.20462262 pounds

[confused]

haha! the world's goin' to end in three years (2012) won't really matter if the engine lasts for 4 years!

[confused]

o.k maybe not but still, it might. I'm jumping to diesle engines forum, so's not to ruin starling's forum more'n I already have. (burnt rubber smell one)