Dubbel bouwverslag Eezebilt pt boot

It's good to see a bit of colour on a PT-Boat. I put a few flags on the plans for this reason. The 'air-recognition' patch is not unusual - some boats in the Philippines painted a white star in top of the chart-room for this purpose, after some incidents of friendly-fire from aircraft...

With your boat you have the option of adding a cartoon character on the chart-room side, as your reference indicates - something like this:

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You can, of course, buy expensive flags printed on silk. But EeZeBilts are meant to be cheap and simple!

So I print out flags on an inkjet - you can see a few included with my plans. They come as a folded pair. I put a bit of string in the fold, and then paint the flag with sanding sealer, or cellulose dope. Then I fold the flag. The ink doesn't run, the dope/sealer makes everything waterproof and glues the two halves together. I suspect that clear varnish would do just as well.

You could also paint that cartoon with sealer, and stick it to the side of the chart-house. Here is a .jpg at the right size. print it out and try it...:

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Laatst bewerkt:
Long time ago, but the motor and esc are arrived finally (I entered the wrong adress). I've put everything in the boat and I did a first test:

The center of gravity is a bit high I think but I will change that later.
 
It runs nice and smooth! But the noise it makes is killing me, especially the high pitch sound. Is that due to the way you recorded it, or is that really so audible?

Thanks,
KR,

Theo
 
I'm afraid it isn't due to the way I recorded it, maybe I should add some more oil to the shaft, when it isn't in the water it don't make that sound.
 
The boat is looking very good in the water, but I think we can make some slight improvements...

Is that able to get up to full speed on your small test pond? What voltage are you running at? I found my boat, using an EMax CF2822 at 7.2v, to go a bit faster than that. Perhaps that noise is associated with some drag - what connector are you using? And what propeller? Different propellers can change the characteristics of a boat quite a lot.

Is the motor warm after a run in the pond? If not, it's probably quite underloaded and you could use a bigger prop, which could make it go faster AND quieter...

The boat looks a little light. Are you using Lipo batteries? I found that NiMh batteries, laid flat in the sub-deck, gave the boat better stability by lowering the CG.

Congratulations on getting the boat in the water before Christmas! If you have a little stand the boat can be proudly displayed on a shelf during festivities!
 
I bought a 25 mm 3blade prop, but a bigger one would be better. I use a Lipo battery but maybe I can put some extra weight in the sub deck. I will post a new video with the improvements later.
I made a stand some time ago:
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That sound...! Yuck. At first I thought of a turbine (nice) but when it came closer the high pitch whine took over (ugh).
I think you should improve on the driveline, not only for the sound but also this boat should be able to plane pretty easily (my Tamar does so on a single 380 motor...).

By the way - I concur with DG's question: Was this flat-out?
Motors and ESC's can make a high pitch whine when not on full throttle so that might be part of the noise-issue. Not all of it, though.
 
Egon, It's depending on the source of the noise. It sounds like a dry bearing in combination with vibrations. At first have a look at the alignement of motor and shaft. What type of coupling is between motor and shaft? All metal or partly plastic? Try to find the best place of the motor straight in line with the shaft. You can test this running the motor and propellor on low revolutions and measuring the amperage. At lowest amperage is best place for the motor. In stead of oil I would use grease. I don't know if you are understanding Dutch. If so do a Google search on Roel van Essen+uierzalf. He is using a type of creme/grease that farmers use on cownipples. It looks like vaseline or petroleumjelly. Regards, Klaas.
 
I understand dutch but this topic is in English bexause Dodgy Geezer don't understand Dutch. I'm just back from the local RC shop and I bought a larger prop and grease, I will first test how the boat runs with this improvements and then I will test the amperage. I use this coupler:

143c6ce57504667f16da4937f3586491.jpg


@setsunakaede the test was most of the time on full throttle.
 
The sound has improved with a bigger prop and some grease but there are still vibrations, the boat also goes a lot faster then before.
 
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