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Author Topic: Andy's 18.5cm tug build  (Read 2660 times)

Andy M

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Re: Andy's 18.5cm tug build
« Reply #50 on: May 21, 2020, 01:12:04 PM »

Hi, this one doesn't use a quadcopter motor, it uses a powerpod from a tiny jetski model. It was going to use radio gear from a small rc car but the steering wasnt up to the job, with only a small amount of movement and really weak, so I decided to change to normal radio gear. As I only had radio that runs on 4.8v powered from a 7.4v pack through the speed controller, I needed to supply the jetski motor with 3.7v, or it would fry it. I thought that adding another motor in series would enable me to use the 7.4v motor supply from esc. It works, I dont know the effect of having one motor loaded with the prop and the other just spinning unloaded, but it seems to work. Someone suggested a device to drop the voltage, but on a limited budget and having the other motor sitting there, I decided to go this way. It seems to work fine, if a bit underpowered, mostly due to prop size, I dont think the motor is struggling at all, so a bigger prop is an option if I can find one the right size.
Answering the question about wltoys v262 quadcopters not being available... The V333 quadcopter is a newer version, it comes with various added features and includes a pretty decent camera. I was able to buy 5 of these at 20 each, a saving of 4 on each one, incredible value. It has slightly different motor pods with longer landing legs but using the same motors. The reason I bought multiples of the v262 and v333 is that if a motor burned out, I would need to buy new motors at about 10 for 4.  As I got some of the v262's at 12 each, I didnt see any point just buying motors when I could get everything else for another 2. They all come complete with a battery, charger, transmitter and spare props, so I have quite a few of these spare now. Even at their normal price of 24, the v333 is a bargain, to me anyway. It enables me to have full control of a model for very little money. Years ago I bought 2 hitec hs 80 micro servos for 25 pounds each, I got 4 of my v262's for less than the cost of these 2 servos.
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Andy M

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Re: Andy's 18.5cm tug build
« Reply #51 on: May 21, 2020, 06:41:07 PM »

I just had a look, the v333 is available for 22.99 with free delivery. As I had a few spare bodyshells, I asked at the post office how much it would be to post the bodyshell. Turns out it is 12 to post it, the same as it cost me to buy a complete v262 quadcopter with its battery, radio, charger etc delivered.? So selling my extra bodyshells was abandoned.
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Tug Fanatic

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Re: Andy's 18.5cm tug build
« Reply #52 on: May 22, 2020, 10:57:21 AM »

AndyThank you.

I fly Model 1, throttle right but most things are set up for Mode 2, throttle left. I notice that the V666 says it can be changed over. Can the V333?. 
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Andy M

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Re: Andy's 18.5cm tug build
« Reply #53 on: May 22, 2020, 11:44:08 AM »

Hi, I am not sure if it can be changed over, the throttle stick doesnt have a spring for centering and is not made like the 'olden days' when all the stick springs were built on the side of the stick mechanism. The springing is internal in the stick base. I will try and dismantle a transmitter to see if it is possible to change this, I have quite a few spare transmitters. Lol. I learned flying with left throttle, but have flown with right throttle before, just needs a bit of practice. These quadcopters are stable enough to practice with the different control layout. The main reason I like these quads is the price, a full flying vehicle, even at 23 for v333 is amazing. And they are pretty tough, my dog has its own dedicated excersise quad, it has had many impacts and bites taken out of it.
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Tug Fanatic

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Re: Andy's 18.5cm tug build
« Reply #54 on: May 22, 2020, 12:41:02 PM »

I really was nor asking you to take your transmitter apart!    :o   I had hoped that there was a simple instruction somewhere.

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Andy M

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Re: Andy's 18.5cm tug build
« Reply #55 on: May 22, 2020, 01:19:31 PM »

I made a new case from ply and balsa for one of my transmitters, I can open that one up easily and have a look, its not a problem. I must say that I have not looked online to see if there is an easy way to do it, but I dont think so due to the layout. The v666 looks like a totally different transmitter. The price is a bit different too!
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Andy M

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Re: Andy's 18.5cm tug build
« Reply #56 on: May 23, 2020, 09:50:46 PM »

Here is what I had in the tug to ballast it to the waterline. 135g of lead, 90g battery (7.4v 2500mah) 16g rx and an 11g speed controller. The hull with walkera micro servo, main drive motor and 'voltage dropper motor' weighs in at 54g. A tight squeeze getting it all in, but I managed it. Just shows how much can fit in a tiny boat. I could have used a much smaller battery of course, but I would have to have made up the difference with more lead. I will probably do that when its finished, might give me a little bit more room to work with.
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RST

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Re: Andy's 18.5cm tug build
« Reply #57 on: May 25, 2020, 10:56:23 PM »

Your two motors in series isn't a great idea.  I remember my father telling me when I was a nip how it doesn't work that way.  The unloaded one inside is probably whizzing away while the one connected to the prop is barely turnng.  There must be a way to turn it around -the model railway guys sometimes use diodes with something like a 0.7v drop on them each time.  Otherwise, maybe just use a stripped servo PCB I think -tried and tested on very small models for several decades on mini-micro models now.
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Andy M

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Re: Andy's 18.5cm tug build
« Reply #58 on: May 26, 2020, 09:54:13 AM »

Hi RST, the one inside is whizzing round but the drive one is as well, the tiny jetski it came from had two of them and it wasnt fast in any way, expecting it to cope with a very blunt hull and quite a weight was a long shot, it does cope, but will never beat any speed records. It moves it about, with an annoyingly high pitched sound, well my wife and kids found it annoying when I showed them the video. I may go for your diode idea, an old guy I used to work with showed me how to make a motor cutout unit for planes so you could have a motor with 2 channel gear controlling rudder and elevator. Pushing a button started the motor which ran the pack down to a preset voltage then the motor cut so that you still had enough power left for servo control. He used to build valve radios as a hobby.
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