homemade boat 5hp lawnmower engine(not complete)

[icedout]

Hello i am 16 years old .This summer 08 I began building this boat. Its 7 ft long 3.5 ft wide. I am using a push mower 5hp engine for the motor. When i first made the boat i used a belt drive system. At first the belt was to loose so when i created a belt tightener i ripped the belt all up. So then i went to an inboard outdrive. I origionally made homemade rc boats. Since this is my first time making a boat that i sit in i made the ratio 1:3 BIG MISTAKE! So now im done with the inboard outdrive im makeing a pure outboard now. Also i just began fiberglassing the boat. I put down a thin slab of bondo on the hull then put the fiberglass mat down. I press the mat down with a flat object so the bondo will get inbetween the fiberglass. After that i put a thick slab of bondo ontop.
What do you think?
http://i26.photobucket.com/albums/c132/icedout782/boat.jpg
http://i26.photobucket.com/albums/c132/icedout782/Picture017.jpg
http://i26.photobucket.com/albums/c132/icedout782/Picture018.jpg
http://i26.photobucket.com/albums/c132/icedout782/Picture047.jpg
http://i26.photobucket.com/albums/c132/icedout782/Picture048.jpg
http://i26.photobucket.com/albums/c132/icedout782/Picture049.jpg

Here is a awesome picture i got of lake erie :)
My main goal is to take the boat all the way around kellys island.
http://i26.photobucket.com/albums/c132/icedout782/DSCN0115.jpg

[thudpucker]

It looks like you've saved yourself enough money on boat construction to buy a Survival suit!

[icedout]

If you understand how a boat floats then you know if this boat will float or not...

[apex1]

Hello i am 16 years old .This summer 08 I began building this boat. Its 7 ft long 3.5 ft wide. I am using a push mower 5hp engine for the motor. When i first made the boat i used a belt drive system. At first the belt was to loose so when i created a belt tightener i ripped the belt all up. So then i went to an inboard outdrive. I origionally made homemade rc boats. Since this is my first time making a boat that i sit in i made the ratio 1:3 BIG MISTAKE! So now im done with the inboard outdrive im makeing a pure outboard now. Also i just began fiberglassing the boat. I put down a thin slab of bondo on the hull then put the fiberglass mat down. I press the mat down with a flat object so the bondo will get inbetween the fiberglass. After that i put a thick slab of bondo ontop.
What do you think?



My main goal is to take the boat all the way around kellys island.
[/IMG]

Welcome here!
Thank you for showing us the result of your efforts.
Obviously everything is possible.............although I doubt that THIS will stay afloat long enough to take you round any island larger than itself.
I do´nt like to discourage you, I like your initiative, but to get this "boat" stiff and afloat in a proper manner you have to invest a lot of money and hassle.
Maybe the best advice is given by saying: search this Forum for a simple design that is within your budget and skills (apart from boldness it seems you have some), and invest in building a safe boat.;)

http://www.bateau.com/proddetail.php?prod=FL12 .................for example

If it comes to GRP works have a look here:
http://www.westsystem.com/ss/use-guides/
the job is almost the same in Polyester resin.

You may also google "stitch and glue boat" to get a clue how the others do such job.

Anyway, all the best and have success.

Regards
Richard

[icedout]

thanks :) ill make a post in about 3 moths here and let you know how this project turns out.

[apex1]

posted twice........:?: :rolleyes: :confused: :( :o :p §<*#'&%

[TollyWally]

While there are certainly better ways to build a boat, congratulations on learning by doing. Your boat may or may not work, exercise caution before getting someplace you can't swim back from.

LOL the first boat I built sure wasn't anyuthing to write home about! If you stick with it some day in the not too distant future you'll build something to really be proud of. If you give it up in a short while at least you'll have some funny stories.

As you get older you will find out that a big part of growing up is all about the funny stories to tell when you get older! Good Luck.

[robherc]

Hmmm, like Apex said, BE CAREFUL & don't go anywhere you can't swim back from.

My guess it that your boat's chines (walls) will want to collapse in on you once it's carrying any ballast (you & the motor) in the water. Also, I hope you used something stronger than the foam I see to bond the sides to your framing. It might be a good idea to put a 1x4 across the middle to reinforce your walls; glue it to the middle of each of those two uprights I see. It'll be awkward to straddle when you're sitting in the boat, but the extra safety of having it hold the walls out will be worth it!

Also, I wouldn't want to hang that motor over the stern (back) of your boat for two reasons:

1. Your transom (back wall) won't be able to handle the weight of the motor hanging off of it & will most likely break.

2. The weight of the motor behind the boat will move your center of gravity too far aft (towards the back) & will make the back wall go down too far...water might come in.

So I'd recommend putting the motor just inside the back wall, and maybe doing an I/O drive there...to get the best balance on your boat & keep the water where it should be....outside!


Best of luck,
Rob

[mydauphin]

Please do not start a 5 hp motor attached to what is virtually a cardboard box. The torque of the motor will break something. And if the pulley or whatever doesn't break first something bigger might and a piece of flying metal may hurt you.

There are many safe ways to build a boat for no more than $100 and engines can be had used for $250. I have built many small boats like this. The only danger is not drowning.

[thudpucker]

I apologize for not seeing this sooner.
That motor you have is a Vertical Crank shaft motor.
It's not meant to run at an angle for very long.
You cannot lay it over to run that shaft at an 11 degree angle. The Carb wont work well and the Oil slinger in the engine wont pickup oil.

That photo is great. Makes a guy want to go out fishing. Maybe you should give up boat building and make some money at Photography?

[icedout]

Hmmm, like Apex said, BE CAREFUL & don't go anywhere you can't swim back from.

My guess it that your boat's chines (walls) will want to collapse in on you once it's carrying any ballast (you & the motor) in the water. Also, I hope you used something stronger than the foam I see to bond the sides to your framing. It might be a good idea to put a 1x4 across the middle to reinforce your walls; glue it to the middle of each of those two uprights I see. It'll be awkward to straddle when you're sitting in the boat, but the extra safety of having it hold the walls out will be worth it!

Also, I wouldn't want to hang that motor over the stern (back) of your boat for two reasons:

1. Your transom (back wall) won't be able to handle the weight of the motor hanging off of it & will most likely break.

2. The weight of the motor behind the boat will move your center of gravity too far aft (towards the back) & will make the back wall go down too far...water might come in.

So I'd recommend putting the motor just inside the back wall, and maybe doing an I/O drive there...to get the best balance on your boat & keep the water where it should be....outside!


Best of luck,
Rob

Thanks for the information.lol that picture was just after the 3rd day of building it. I used 4 inch screws to hold the side of the boat walls to the main floor. Then i have 5 2x4 pieces of wood across holding them on also for extra support. You cant see that in that picture. Trust me im not making this thing out of wood glue and paper. I x2 reinforced everything on the final project.For the transom i took that wood out and used 3/4 pressboard wood. Not that junkey scraps of wood glued together. I forget the name of it. For the engine i got huge 3/4 inch diameter 5 inches long screws.

[icedout]

I apologize for not seeing this sooner.
That motor you have is a Vertical Crank shaft motor.
It's not meant to run at an angle for very long.
You cannot lay it over to run that shaft at an 11 degree angle. The Carb wont work well and the Oil slinger in the engine wont pickup oil.

That photo is great. Makes a guy want to go out fishing. Maybe you should give up boat building and make some money at Photography?
Maybe i didnt give enough information on what im doing with the motor...
the motor is gonna be placed with the shaft vertically on the back of the boat. Like an outboard would look. Then a shaft is going to go down to that 90* gear box. So now the shaft is at a horizontal angle sticking out the gear box case underwater. On the vertical shaft going down into the gearbox casing im going to mount a air propeller to the vertical shaft so it will pressurize the gearbox case itself so no water will get in the casing while its underwater and the engine is going.
http://i26.photobucket.com/albums/c132/icedout782/boat.jpg

[robherc]

Hmmm...think you could put the engine & gearbox on the inside of the transom, then just run the prop shaft through a sealed bearing in the transom?
Your prop might be a bit higher & out of the clean flow underneath your hull, but you'd gain a lot in safety by not leveraging your transom down soo much, and by keeping your gearbox out of the water.

[icedout]

Originally what i did is you can see that hollow tube in on of the pictures. Well the shaft came out of there to the propeller. The hollow tube was higher than the water line so no water could get in the boat. The only proplem was when i did that inboard outdrive was the engine was having a hard time starting up at an angle.

If you all were interested the boat hold 410lbs before water will rush in.

[robherc]

410 lbs, not bad, how about with the motor mounted outboard?
Try testing it that way with about 150lbs in it...see how much freeboard you have left. Anything less than 8" freeboard and you'll be at a SERIOUS risk of having water come in the boat from waves out on the lake.

I'm not trying to tell you you can't do it, I'm just trying to help you avoid getting swamped on your maiden voyage ;)

[icedout]

Even if u think this is or isnt a good idea on what i am doing picture yourself as 16 again. Wouldn't you want to be doing what i am doing right now? I love the water so much. And I know when to go out or not to go out in this boat. The conditions have to be perfect on the lake.Thanks for the help and feedback though. I Just finished fiberglassing and applying the primer now.Ill post a video on my first time out with it in about 2 months here.

[robherc]

OK, I'm not telling you it isn't a good idea...BECAUSE I'm picturing myself as 16 again...that's why I'm trying to approach it more from a "this is how you could make it a bit safer" standpoint, instead of a "don't do that, you'll hurt yourself."
I think it's great that you're able to do something I only dreamt of doing when I was your age, but I don't want to see you injured doing it...and I think having that motor hanging behind your boat is going to put it (the boat) at a precarious angle...if you found a way to hang the motor on the inside of the transom, I'd be happy :-)

[messman]

I am not a builder YET, but I would recommend that you take some of their advise my young friend, they do know what they are talking about. I am a member of a couple of sites like this one and I have to say that these guys are probably the must knowledgabe around. By the way Kid you got your self some get up and go, and I like that. Just make sure you don't get up and hurt. Please keep us posted with what you are doing, more pictures would be nice.

Chris

[icedout]

Sorry if i got you guys feeling I wasn't appreciating your help. It actually helped alot. I actually decided to use some of your suggestions. I just don't like people just saying "oh its gonna sink"...Thats the worst thing you could say to a person building a boat. Best regrets Icedout :)

[apex1]

Sorry if i got you guys feeling I wasn't appreciating your help. It actually helped alot. I actually decided to use some of your suggestions. I just don't like people just saying "oh its gonna sink"...Thats the worst thing you could say to a person building a boat. Best regrets Icedout :)

GO.............
do it...........
find out yourself what could have been done in a different way (sometimes a better). That is the way learning goes, trial and error, usually more error.
Keep your back safe when you run your shakedown test.
Come back here after your first experience is in the pocket... and let us tell you how it can be done to more satisfying results.
All the best... And allways an inch water under the keel! BUT NOT MUCH MORE:D
Regards
Richard

[PAR]

Actually you could make that boat work, but it'll be heavier then necessary. Such are the trials of your first boat.

Lets address the boat issues first. Aside from the obvious shape limitations you have some structural issues to handle. The Bondo on the exterior, under the mat will limit the "grip" the polyester will have on the plywood and particle board. It will likely sheer fairly quickly, but you'll learn enough from this boat by then. With out having some taper in the stern quarters (plan view) she'll be hard steering, but you'll get by with the modest power you're providing. It appears there isn't any rocker in the bottom panels, which will cause more handling issues, but it's unlikely you'll get this girl to planning speeds with your available power, so again not much of a big deal in the total picture.

Particle board isn't especially strong, in fact you can break it pretty easily. This means you need to add a good bit of fabric (cloth) to increase it's strength and waterproof it. Mat doesn't offer much more then bulk to a laminate. Cloth is the ticket. Unfortunately, polyester resin, being what it is, requires you use alternating mat/cloth layers to gain strength and insure a reasonable bond. In short, get some cloth into that laminate.

The foam at the seams will keep out the water, but just for a short time. Covering the outside with mat and cloth will go a long way toward water proofing her, but it still has strength issues, so carve up the oozed out foam with a hot knife or hack saw blade and shape it into a fillet. It doesn't have to be an especially big fillet, just enough to make a reasonably smooth transition from the inside of the bottom planking to the sides. Over this apply at least two layers of mat & cloth, extending up the hull sides and bottom several inches. The corners of the transom and the bow need to be reinforced the same way. Once you do this, the boat will be fairly rigid, but will still have floppy sides, especially in the middle of the boat at the rail. To fix this, it's common to use a thwart or bench seat box of some sort. This braces the sides so they don't collapse in on you from water pressure. I'd build two of them, one at or near the transom and the other just forward of midship. Also consider a small wedge shaped piece at the bow to help meet the pounding chop.

With these pieces installed, glued and 'glassed in place, she'll be reasonably stout and safe enough to try out in water deeper then you are tall.

Yep, those "L" head vertical shaft engines don't like anything but sitting bolt upright. You can live with a few degrees of tilt, but just a few or it'll self destruct from lack of oil. It also looks to have a "suction" type carburetor, which means the fuel is sucked up through the bottom of the carb. It's possible you could extend the two tubes that come out of the bottom of the carb/tank mounting flange to a remote tank or you could just live with a quart sized fuel tank.

Ideally you'd want a clutch of some sort, which would make it easy to start the engine and come to a stop, without having to kill the motor. This is a complication that may not be necessary. You might want to have a look at some garden tractor or riding lawn mower parts to see if you couldn't rig up something that gives you a clutch and maybe find a reverse gear in the process too.

As has been mentioned, using a lower leg from an outboard would save you a world of fabricating, plus you could get a reverse and neutral setup to boot.

Without the lower leg, your options are only limited to your inventiveness, which I congratulate you on. I was much like you, not having a lot of money and wanting to go fishing with my own creation. My first boat was 8' when I was 12. I couldn't afford any kind of motor so I rowed it. You'll learn a lot from this little project and the next one will be a fair piece better.

As far as getting the engine to spin a prop, well you have a pretty good handle on what you need, with some alternative ideas to think about. I wouldn't give up on the inboard idea just yet. It's an easier thing to do and rigging up reverse and neutral is just some V belts, pulleys and an idler wheel or two. You could use a simple lever to engage or disengage the prop. You see, trying to start an engine with a prop on it, while it's in the water is pretty hard to do, not to mention the boat will start moving the moment you do get the engine started.

You'll figure it out, just don't limit your options. First get the boat water tight and strong enough to take you fishing, all the while thinking about how you want to push the girl. You can do it, thousands of us have been down this road too, so don't let the nae sayers get you down, "screw 'em" I'd say if it was me. Now get back to work and send in more pictures of progress.

[c_deezy]

Stop, do not continue with this project. And don't even think about trying to take that thing around Kelley's Island, you will die. Unless you strap this thing on the back of your parents cruiser or something.

That being said, there is a wealth of info on this site, not trying to discourage you from building a boat, just build one you won't drown in. Find some proper plans, get some proper materials and start over.

[Frosty]

Do it,--I did all this stuff, you gotta find out why you are wrong.

Take warm clothing and a life jacket and a fully charged telephone in a plastic bag. Tell some one where you are going and for how long.

Don't go too far out, try to stay in shallow water and keep from the current. Can you make up an anchor and some rope.

Safety costs nothing.

[robherc]

c-deezy-

You're letting down the rest of the forum by making that as your first post. If you re-read this thread & pay careful attention, you'll find:
1. Telling him "don't do it" will have no effect other than to encourage him to do it, and do it without heeding other safety advice...(good one!)
2. EVERYONE who has posted in this thread has given him information on how to improve his little craft to make it more safe, and other safety procedures that he needs to follow.
3. Most of us who've replied to him are forum veterans, and veterans of many hair-brained ideas (that we lived through) ourselves...so we probably have SOME idea of what we are (and should be) telling him!
4. The last post in this thread before your "smart" remark was over 3 weeks old!!! You're just a BIT late as he likely has already made his maiden voyage.


Next time, please THINK before you post....ESPECIALLY when a young man's life could very well be at stake!

[c_deezy]

I knew I would take some heat for that and that's fine. Granted I didn't see how old the thread was, and its still winter in Ohio so I doubt he's taken the boat out, since most of the ponds/lakes/rivers are just starting to thaw out up here.

You 'forum veterans' should have given the kid some better direction, rather then letting him waste a bunch of money on the wrong supplies and possibly put his life in danger. If he wants to try this out at the local pond, go for it but don't take it out on Erie and attempt to go around Kelley's. It's good that he is 16 years old and interested in boat building, best thing he could do is find a local boat repair shop and try to find some part time work. Every week during boating season somebody drowns because they underestimate Erie or just don't know any better, I cannot believe he would be encouraged to take a boat made of particle board, 1/4 ply and bondo out there. Even on the best day, things kick up quick up here and one good cruiser wake and he's toast, not to mention the wakes from the ferrys that run all over that area.

[robherc]

Hmmm...looks like you read about 5% of my post...you're still failing to read & think before speaking.

1. Telling him "don't do it" will have no effect other than to encourage him to do it, and do it without heeding other safety advice...(good one!)
So, you want him to do it WITHOUT taking ANY safety precautions out of spite???

...maybe you should go back and re-read his posts stating very plainly that any attempts to discourage him will be completely ignored!
In light of that, maybe re-thinking your approach and simply encouraging him to take a more cautious & safe approach, and to let his parents in on his plans...and making sure they know exactly when he's making his attempt, so they can stop him (which it is THEIR place, not ours, to do), or they can watch him to ensure that he's safe!


OK, so now READ and THINK before speaking, PLEASE!!!!!

[c_deezy]

Alright then, where does anybody mention registering the vessel? Coast guard requirements, lighting, flairs, etc? VHF? Only mention I saw of safety was a survival suit, a life jacket and a cell phone in a plastic bag. That cell phone isn't going to stay dry for very long when he's getting tossed around in cruiser wakes.

You can keep dinging me rep wise, and insulting my intelligence if that makes you feel good. Fact is you are encouraging a 16 year old that he can take this boat out on Lake Erie. And how do you know this kid isn't going to load this boat up, drop it in and head out because you all said 'give it a shot, it'll be fine, you'll learn what to do next time'. What if there is no next time???

I applaud his intentions and his interest/desire in boating and encourage him to learn by doing. JUST DO NOT TAKE THIS BOAT ON LAKE ERIE.

Kid - if you read this and feel you need to prove me wrong, more power to you. But as mentioned let people know what you plan on doing, I seriously doubt your parents would allow you to make a Lake Erie voyage in a 7 foot boat, but just in case they do let the Coast Guard know in advance.

[PAR]

Not for nothing C_deezy, but most here have earned the respect they get. You've shown a remarkably unique method of garnishing the same.

Kids, like it or not will do what they want, regardless of what a few negative comments on an open discussion forum might recommend. Knowing this reality of life, it's often best to encourage young, inventive minds and let them learn the same way the vast majority of us did, the hard way. I've blown up my fair share of contraptions on my quest through a few engineering degrees.

You mention having you intelligence insulted, but frankly you haven't displayed any yet. No one here has a clue what you are, what your about, you experience level, are you a designer, an engineer, an industry professional. Yet, you expect some to take your words of condescending wisdom to heart. Any one with some semblance of intelligence would know better then to grab the microphone, start yelling and expect anyone to pay attention.

In short, you'll need to earn the respect and trust of this board to over come your less then austere beginnings.

So, how about we try this again. Who are you, what is your education level, industry experience, most notable work, etc?

For what it's worth, I was 6 years old when I stole the family cruiser and headed out into the Chesapeake Bay. I didn't hit anything and was found, out of gas by a family friend, heading back to the island from work. Good thing I didn't have a buddy like you around to save me from myself.