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Physics Project: Mini Electric Motor Boat

last photo ←

For physics, I had to construct a boat that would successfully race down a 3m PVC track. We had limits on the dimensions, as well as the total voltage of the battery. The boat is really ugly, but it is fully functional. I attempted to model it after a catamaran, but it was no where near being the fastest in my class. It is made mostly of pink construction foam and hot glue.

I did not pick the paint, my partner did because I didn't care. It is also her handwriting on the boat.

I KNOW IT'S UGLY! But please feel free to ask questions or post comments.

59 comments

1-40 of 59

Aug 30, 2011. 9:04 AMbvillaflor says:

don't know if this one will help... i'll post soon our model of this type of boat...
we do racing here in our place using only mini 4wd motor here's the link if u want to see how it runs... http://www.youtube.com/watch?v=uVWx3BgTbmk&feature=mh_lolz&list=HL1314718311

Jan 12, 2010. 7:30 AMrrsasuke24 says:

which kind of motor did u use?
is it a dc motor?
how did u make ur propeller?

Jan 12, 2010. 12:53 PMbassclarinet23 (author) says:

Sorry, I don't really know. It was from a Hobby Shop and the packaging was all in Japanese so I didn't have a clue what it said. The motor reads "plasma 4WD". It took 4AA batteries to power it. The propeller was from the hobby shop too (premade).

Aug 27, 2010. 8:56 PMI R ASSASSIN says:

oh then that motor must have been a tamiya mini 4wd car motor........sadly these mini 4wd don't sell anymore

Jan 13, 2010. 2:30 AMrrsasuke24 says:

Thanks. It's ok. I'LL try cutting something or use a mould to make the propeller. I'VE GOT the circuit done and the motor is spinning quite fast.so I think it can run at a good speed. Was ur boat quite heavy?

Jan 13, 2010. 4:42 AMbassclarinet23 (author) says:

Our motor rattled against the foam and made a really loud sound that was quite irritating. You should post a slide show when you're done!

Jan 13, 2010. 4:40 AMbassclarinet23 (author) says:

It was really light until we added the motor and battery. So yeah, it was pretty heavy.

Jul 30, 2010. 2:50 AMrrsasuke24 says:

Ididnt get the Torque Part.

Jul 24, 2010. 4:43 AMknektek says:

I would seriously comment on the circuit. First of all, the circuit will drain off the cells in a few minutes. My next point is that if there was an accident was to occur, as worst-case scenario would be if the batteries got submerged in the water and the casing melted causing fumes to produce. You can get a casing for all of this that is water-proof.

Jul 21, 2010. 1:21 AMkid cudi says:

what is the easiest way to make an engine

Jan 14, 2010. 5:20 PMZem says:

Nice project. What did you use for the shaft? And how did you attach it to the motor?

Jan 14, 2010. 6:22 PMbassclarinet23 (author) says:

Thanks! We found white plastic straws at the hobby shop, as well as a flexible rubber coupling that the propeller screwed into, and the other part went around the spinning part of the motor. (The propeller was attached to a metal stick.) I accidentally broke it while trying to change the battery to video tape it, so I'll disassemble it and take pictures of it to show you. The design wasn't the best (and it was ugly :)), but it didn't splash and it ran really straight. My teacher specifically commented on these elements (they were outstanding compared to some others that thrashed through the water). Unfortunately, however, the battery ran low (and I didn't want to break it trying to change it) and the overall design made it slow (methinks). :( Well, all that matters is that it worked, we just didn't get the extra credit for having the fastest boat. Sorry to make this so copious, but if you have any questions, I'd love to answer them to the best of my ability.

Jan 14, 2010. 7:23 PMZem says:

Ooh, cool. I'd love to see the pictures. Well, the design doesn't always have to be the best, if it works, it works. One tip though.. You should have made the batteries easier to get to XD.

Jan 15, 2010. 2:46 PMbassclarinet23 (author) says:

I posted some more pictures, concentrating on the propeller.

Jan 15, 2010. 6:59 PMZem says:

Awesome! Thanks!

Jan 15, 2010. 7:02 PMbassclarinet23 (author) says:

The photo quality isn't great, but you get the picture. (Punny!)

Jan 15, 2010. 7:31 PMZem says:

Ha! Haha! Hahaha! You so punny!

Jan 16, 2010. 4:49 AMbassclarinet23 (author) says:

I like this site because people are smart enough to get subtle little jokes. : [}

Jan 16, 2010. 9:24 AMZem says:

=D Yup!

Jan 15, 2010. 12:40 AMrrsasuke24 says:

I have connected three 9V batteries to the motor now. Earlier I had 2 of them. I tried the boat in our society swimming pool but it was a bit low on power. I'm getting problems with the shaft and the propeller. the motor is rattling due to the weight of the propeller which is made of cardboard. I'm trying to stick it in place so that it doesn't rattle.

Jan 15, 2010. 2:46 PMbassclarinet23 (author) says:

I posted some more pictures, concentrating on the propeller.

Jan 16, 2010. 7:55 AMrrsasuke24 says:

thanks! I'll check them out .

Jan 13, 2010. 5:37 AMrrsasuke24 says:

Do u have any ideas as to how I can make a propeller?

Jan 13, 2010. 3:03 PMbassclarinet23 (author) says:

I'd say it'd be easiest to find one from a toy or something. Otherwise, you could cut up and bend a plastic (gift) card. That's what some other kids in my class did. Just be careful not to cut yourself or others when it's spinning.

Jan 13, 2010. 2:33 AMrrsasuke24 says:

I got the motor from one of my remote controlled cars. The car doesn't work because I lost the remote control.

Jan 13, 2010. 4:43 AMbassclarinet23 (author) says:

Oh, beware of torque. The first couple test runs (before adding rudders) resulting in the boat rolling over because the motor was so powerful.

Jan 13, 2010. 4:41 AMbassclarinet23 (author) says:

Okay, way to be resourceful!

Jan 12, 2010. 7:53 AMrrsasuke24 says:

Thank u for the reply. I will take ur advice and use trial and error method.
Can u tell me where do u live and when ur online so that i can ask questions at that time.

Jan 12, 2010. 12:55 PMbassclarinet23 (author) says:

Thanks for showing so much interest in my project. My partner and I are really grateful for your enthusiasm.You can ask at any time. I generally check this site once every hour or two (depending on how busy I am), so just post at your own convenience and I will reply as soon as I have the chance.

Jan 12, 2010. 3:53 AMrrsasuke24 says:

Will a thick cardboard work as a good rudder?
I am not able to find any metal to make a rudder. Iam going to cover it with plastic or tape so that it doesn't absorb water.

Jan 12, 2010. 4:40 AMbassclarinet23 (author) says:

I would think it would suffice, as long as it is water-proofed. You'll have to find out through trial and error to be positive, though.

Jan 11, 2010. 12:18 AMrrsasuke24 says:

Hello,
which class r u in?
Ireally liked ur project . I'LL SURELY TRY IT.

Jan 11, 2010. 4:39 AMbassclarinet23 (author) says:

It wasn't the fastest but it worked. Do you go to my school?

Jan 11, 2010. 5:28 AMrrsasuke24 says:

No.
just wanted to know what projects u get over there .
I live in India. I have an assignment to make a working model.
Thanx for ur post .

Jan 11, 2010. 12:40 PMbassclarinet23 (author) says:

Oh, I'm in Physics I Honors. A HS Freshman level class here.

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Jan 10, 2010. 12:07 PM

Kiteman says:

In the circuit diagram, the symbol you have given as a motor is actually a resistor.

The most recent symbol for a motor is a circle with a capital M inside it.

Jan 10, 2010. 12:19 PMbassclarinet23 (author) says:

Okay, I changed it.

142

Jan 10, 2010. 12:24 PM

Kiteman says:

LOL, you had a whole conversation without me!

(You note them all as resistors? So how can other people follow your diagrams? That would not be tolerated in a UK school at any level!)

Jan 10, 2010. 1:09 PMbassclarinet23 (author) says:

I think it'd be really cool to go to school in the UK (sounds like a good education), but I have a fear of long distance journeys over massive bodies of water, plus I'd be a little embarrassed. :)

142

Jan 10, 2010. 1:19 PM

Kiteman says:

You'd be popular. I teach a boy who used to live in Virginia (says "ornge" instead of "orange"), and he is popular simply because he sounds like the movies.

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