Got an engine, but no boat

[The Big Wood]

Hello all. I live on a 35 acre lake and have been dying to get a remote control boat to play with. But I'm the type that likes to tinker around with every aspect...don't give me something in a box for me to throw in the water and go! I've also played with RC cars in the past, but I got too frustrated with the lack of run time with the electrics. I bought NiMH batteries and they still didn't keep me satisfied (too powerful of a motor I guess :rolleyes: ).

I haven't had the time to start a new hobby, but fate has provided a jump start to this boating interest. My Ryobi trimmer rounded out the coupling for attachments at the end of the upper shaft. None of my attachments would operate, so I purchased another trimmer. Now I have a 31cc 2-stroke that runs great, but has no apparent use.

I want to take that engine and stuff it into a hull, throw in the radio components and drive components and enjoy. Where do I start? I have no knowledge of boating, and this forum seems to be the best start I have found. Any suggestions and experiences from you pros?

Our lake is usually calm, with an occasional ripple that is no more than 1 inch high. I will not be in the water when the storms come through that make the lake choppy! Also, I need to figure a way to keep the engine rather quiet. Gas engines are not allowed on our lake, but no one follows the rules around here anyway :rolleyes: .

Thanks for your suggestions, pointers, and links!
Anthony

[The Big Wood]

Ok, did a little more research and ran across the below web page. I like this catamaran design, and it says these hulls are ready for a trimmer engine.
http://www.redlinestands.com/images/60limecat.jpg

Now I need info on how to put things together if I were to buy something like this. Is this hull design good for speed and the type of water conditions mentioned above?

Anthony

[Hydro Junkie]

The boat would be great for what you have in mind. The engine is the question. All weedeaters are air cooled, which means you would either need to find a way to get LOTS OF AIR FLOW inside the cowl, or just plan on not using the cowl. Now is where the big question comes in: which way does the output shaft spin? Unless modified, all inboard boat engines output shafts spin clockwise. This means that all boat specific flex cables and a majority of the props are designed to spin clockwise. If the engine spins counterclockwise, you will either have to do some creative engineering or find props and flex chafts designed to spin backwards. Since your engine isn't a standard maring engines, you will most likely have to make your own exhaust header, if you want to use a tuned pipe, or stick with the stock exhaust. Either way, you will need to get the exhaust out of the boat to A)keep the engine from stalling due to lack of air, and B)keep the inside of the boat from getting coated with oil from the exhaust. If you can use the engine, you might be well advised to contact Warehouse Hobbies. They build and sell the Enforcer line of boats and can probably help you out with hardware. In the meantime, Good Luck

[Ron Olson]

OK, I'm being totally honest here with you. The Ryobi isn't the best engine in the World to put into a hull like that. You'd be lucky to see 25 MPH out of it and finding the hardware to install this in a hull is almost impossible.
The hull that you are looking at is what we call a splash. Actually it is a splash of a splash. Someone buys a hull from a Manufacturer, makes a mold of it then sells them on eBay or wherever at a lower price. In turn, you get a rip-off from the original that is usually done poorly. This hull was splashed from an Expresscraft.

[Hydro Junkie]

How could you tell Ron? The hull looked good to me in the pic :confused:

[The Big Wood]

Ah geez Ron, you are making me change my mind! ;)

For the amount of money and time I would put in to this project, 25 mph just doesn't sound like it would keep me interested. I was hoping for more than that. I have a short attention span and spend a month or two playing with a new toy/hobby, but then it gets old and I put it away and allow it to collect dust. Maybe I need (excuse me, WANT) a better engine. Oh no, it's already starting...more power! :D

I like the style of the cat, but what would its turning radius be? I imagine it not turning quickly, which would not be what I would want. To keep my attention on this hobby, I would need to do sharp turns and speed. Speed alone would get old for me. I picture the deep v hull design being a great combo for speed and turning, but it doesn't look as cool as the cat to me. I might would sacrifice some agility if the cat can perform close to that of the deep v hull.

Anyone got another bad vote for this engine? Just give me one more and I'll jump to a better engine....please. :p

[Ron Olson]

HJ, you learn after a while. Expresscraft doesn't make the hulls in all of the colors that these Splashers are selling on eBay. I've seen one of the splashes that was done of an Aeromarine mono that another was selling. Real heavy 'glas lay-up and lousy wood for the stringers. A good hull maker will make his molds compensating for shrinkage and warpage that happens while the epoxy is drying. A Splasher just makes a mold and doesn't worry about that.
I'm not trying to turn you completely off but letting you know up front what's going on. I don't believe in BS'ing somebody. It leads to big time disappointment later. We get a boater, we like to hang onto them!

[Chris LaPanse]

The engine would probably work, but, I would agree that you would only get between 20 and 30 mph (depending on the setup). As far as big gas boats go,
Warehouse Hobbies (http://www.whobbies.com) or Aeromarine (http://www.aeromarinerc.com/) are probably the best places for hulls, engines, etc. You can buy ready to run, kits, or just the bare hull from both of them. Good luck with whatever you choose :D

[Hydro Junkie]

I've got an idea for your engine. What about putting a large aircraft prop on it and make yourself an airboat? They work on water, wet grass, snow and sand(though not as fast on sand). Since the rudder is in the propwash instead of in the water, they can be a challenge to drive, used year round and not be boring. The only thing is, with an engine this big, you would have to build a fairly large boat, for stability, or mount the engine down in the hull and "belt drive" the prop. That would mean pulleys and V-belts and more fabrication work than the "prop on shaft" method, but you would have a real challenge on your hands to get it to work. What do you think?

[The Big Wood]

I would love to have a hovercraft. Driving one would be a challenge I would think, but I wouldn't think this engine would have the power to lift its own weight...could be wrong.

I was cutting my grass with my pushmower a couple of days thinking to myself "how can I put this 6.5 HP motor in a boat?" =)

[Micho523]

Lol. I have had the same thought while on my riding lawn mower with a 15.5 hp engine in it. But then I figured that if I did that, it would be better off as a manned craft rather than rc. Could you imagine how much torque the steering servo would need?!

[DLM]

Big Wood, there are some plans which are easy and the boat is called the THING and Mr. Olson knows where the plans are in the rc store. The THING is made for gas and to heavy or big for electric. Check it out. There is a back issue of rcbm which has an article in it!

[Chris LaPanse]

He isn't talking about a hovercraft, just an airboat. You could buy plans for one (the gatorbate (http://www.rcstore.com/rs/general/listproducts.asp?catid=29&catego=PL) ), or you could try to scratch build one. And, because, it is still dragging in the water, it will be more controllable than a true hovercraft. :D

[KanaiDude]

I have talked to the guy that made that hull several times and seems like he really knows whats going on, he does sell them on ebay but I think he does them right, his feedback is incredible and his boats are beautifull I'm thinking of getting one before he's done making them... JM2cents