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Author Topic: First run of first boat... don't laugh  (Read 3491 times)

NobbySideways

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First run of first boat... don't laugh
« on: June 27, 2015, 04:58:50 PM »

Here is the Fairey Huntsman I've been building; she isn't finished but I wanted to check everything was good with the trim before I started to finalise things. I didn't show much of the later high speed cornering as my girlfriend didn't take footage of that, this is just a quick idea of its pace etc, we were running for about 20 minutes before I decided I didn't want to push my luck so I packed in.


http://youtu.be/Kk1Ft8VBmQY


A couple of things I've leaned; if I heel it over too hard when cornering she starts to skip and hop. If I'm gentler its fine.


Sometimes when I opened the throttle the revs would go crazy with what I would guess is cavitation, then it would quickly get quiet and she was off like a scalded cat.


Now I'm happy she runs ok I'll get the cosmetics sorted. All the important stuff like curtains and seat covers...  {-)
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boatmadman

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Re: First run of first boat... don't laugh
« Reply #1 on: June 27, 2015, 09:09:58 PM »

Looks good and runs well.


I think what is happening when you heel over too hard is that the prop is drawing in air..mine does that as well..makes a buzzing sound and slows down until its back on an even keel and the prop bites again.


You have found the answer..dont turn as hard at full speed!


I have also bent my rudder by turning hard at full throttle!
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Stavros

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Re: First run of first boat... don't laugh
« Reply #2 on: June 27, 2015, 09:57:21 PM »

Right a couple of observations
 
1  ......far to much rudder movement.....cut it down yuo only need about 15mm off the centre line reason u will hop skip and jump like it does.
 
2 Needs far more weight so she can actually turn....running far to light.
 
 
Dave
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NobbySideways

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Re: First run of first boat... don't laugh
« Reply #3 on: June 27, 2015, 11:10:01 PM »

Gents, both very helpful and constructive replies. I've also had it suggested from a reputable source that it's running too much power.  :}

My turning improved as I got less heavy handed; it wasn't just my boats first time, it was mine too. I'm learning, and I appreciate all the help and advice I've had so far. I'm a bit nervous about adding more weight as she sits very low in the water when slow or stationary, however as soon as you crack the throttle open she sit much higher.
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canabus

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Re: First run of first boat... don't laugh
« Reply #4 on: June 28, 2015, 08:36:42 AM »

What motor, battery and prop are you running?
Dam fast boat!!!!
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NobbySideways

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Re: First run of first boat... don't laugh
« Reply #5 on: June 28, 2015, 09:18:59 AM »

It's a Turnigy Aqua-star 4084-1050. I was planning a smaller one but the smaller one went out of stock after I had bought everything else and this was the next closest thing with regards to Kv that I could get at short notice. 40mm raboesch 3 blade brass prop, two 4S 4000mah lipos into a 160a Turnigy speed controller. I used two because I bought one before the motor became unavailable and the one I bought didn't have a high enough C rating. By buying two battery packs I spread the current over two and also had the side benefit of being able to mount the batteries low in the hull either side of the prop. It's been an interesting experiment.
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essex2visuvesi

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Re: First run of first boat... don't laugh
« Reply #6 on: October 11, 2015, 12:38:37 AM »

Does that ESC have programming options?
If so look for a soft start option.  This will give a gradual acceleration even if you slam the throttle wide open, also if the Transmitter has mixing you could mix the throttle and the rudder so the more rudder you have the less throttle is available, I have mine set to 40% throttle at full rudder.


I'm running the same Hull as you but with a 800Kv Outrunner from a 600 class helicopter on 6S again, over powered but huge fun
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NobbySideways

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Re: First run of first boat... don't laugh
« Reply #7 on: October 12, 2015, 10:44:16 AM »

Thanks, I like the idea of the rudder/throttle mixing, I hadn't thought of that. The ESC may have programming but its pretty confusing... The mixing I can do on my TX. I programmed the TX to have a non linear steering giving more sensitivity about the midpoint and winding it down at the extremes, combine that with more practice and I'm actually starting to get the hang of it... famous last words...
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inertia

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Re: First run of first boat... don't laugh
« Reply #8 on: October 12, 2015, 11:22:03 AM »

Nobby
You already have a mixer for rudder and throttle - in fact you have one on the inner edge of each hand. They are called thumbs. Just don't push the LH one so far up the box whenever you move the RH one.
IMHO scale model powered boats in general are sailed too fast and turned too tight to look real. If you want something that travels at warp speed and turns like a demented bluebottle then build a proper fast-electric racing model. H31 is a fast motor cruiser and can be made to look the part if you avoid shoving the stick to the edges of the box.
From what you say you're beginning to realise that.
The model aeroplane boys discovered how to use proportional radio properly in the sixties - it's long passed time that boat modellers got the hang of it, too.
Dave M
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NobbySideways

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Re: First run of first boat... don't laugh
« Reply #9 on: October 12, 2015, 11:33:34 AM »

I think fast electric may be my next port of call. I've got the bug....
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AlanT

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Re: First run of first boat... don't laugh
« Reply #10 on: October 12, 2015, 11:39:37 AM »

Nice to see the sun out at Warminster....


Currently building a sea commander with much less power.. ;) .


I would second the installation of a lower powered motor and I'm still not convinced brushless is necessary for this type of boat but as you've invested in all the other bits that go with this type of setup I guess your stuck with it....


Hope to join Warminster Club soon, so maybe see you at the lakeside .


Regards


Aan
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