Can I connect a small motor to a servo lead?

[SoupParticipant @soup]

Posted by ashley needham on 25/04/2013 08:03:26:

I remember having non r/c motorised boats as a lad and playing with them at the seaside.. gosh. the ones I used to have never seemed to perform very well.. they were either slow, unreliable or just simply packed up very quickly.

Apart from the (mainly lump of plastic) toy boats, the first model boat I had was from the KeilKraft EeZeBilt  range (the Terrier I think). One of this range (if they were still made) strike me as ideal introductions to small gear. These could be operated with a mini servo and a Pico1A (or similar speed control taking motor power from the R/C battery. No prizes in scale fidelity/looks or performance but an easy 'in'.

Already done :-**LINK** Seek and ye shall find.

Edited to correct minor typos

Edited By Soup on 26/04/2013 12:17:56

[ashley needhamParticipant @ashleyneedham69188]

Telstar has it. Unless you are the sharp end, you do not need to know.

I had just written a bit more and then scrubbed it.

We have diverted from soup`s musings.He asked a fairly simple question, worthy of a few thoughts to be sure, but it has become a quagmire of arcane knowledge now.

Ashley

Edited By ashley needham on 26/04/2013 14:48:04

[ashley needhamParticipant @ashleyneedham69188]

Soup. I like that site. I would like to say it brought back memories but I didnt do much boat building as a lad!! Did lots of Airfix building instead.

Not sure about the "easy in"..converting plastic or small boats such as the KielKraft is tricky. The only things I have converted are the RTR Severn and the Argos battleship (see album) and they were relatively large. Ashley

[Dodgy Geezer 1Participant @dodgygeezer1]

<i>"…Not sure about the "easy in"..converting plastic or small boats such as the KielKraft is tricky…."</i>

The big ones can take a radio, but the little ones are a bit fiddly.

Which is why we have the '50+' range of larger boats, still to the same 'EeZebilt' design, which are easier to install modern radio kit into….

[ashley needhamParticipant @ashleyneedham69188]

Thats what it needs, period charm but a bit of room to install the gear.

I shall peruse your site, very interesting, thanks

Ashley

[SoupParticipant @soup]

Posted by ashley needham on 26/04/2013 21:21:04:

Not sure about the "easy in"..converting plastic or small boats such as the KielKraft is tricky.

The "easy in" was to converting smallish boats to R/C not R/C boat modeling itself. It would be cheaper (er not cheap) to buy a (say 3~4' )beginers kit and its internals and use that to get on the water, hopefully by the time you are ready for something more scale/complicated you will know enough that it wouldn't be a leap in the dark.

[Malcolm FraryParticipant @malcolmfrary95515]

I can go along with that – my first efforts involving radio were in the 2 feet and a bit size range – big enough to work on a range of water conditions, big enough to use standard size commercially available components, small and simple enough for easy transport and relatively easy to keep within a tight budget.

The availability of smaller gear and its general reduction in cost means that a great many more projects are possible to more people with a lot less hassle. Mother nature still says that a small boat on lumpy water isn't going to last long, though.

It would be nice if the article writers who do plastic magic could actually tell us what motors are being used more often, and, if using non standard or unavailable components, tell of an alternative.

[ashley needhamParticipant @ashleyneedham69188]

I would imagine a lot of "plastic magic" builders DO NOT KNOW exactly what motors they use.. after all a "cassette motor" surely covers an awful lot of things. If you buy a "cassette motor" from one supplier..how do you know you are getting the same thing from another. ?

A good point though. There are several small motors that would do the trick from established manufacturers, but I have the feeling that plastic magic conversion is about using bits that you "find" and adapt and not neccessarily purchase especially for???

Radio control gear is of course universal and you pay yer money and you buy as small as you want.

Plastic magic is surely one of the more difficult ways of getting a boat on the water, and , unless you REALLY REALLY want a particular model, one of the more..unusable.

Ashley

[Malcolm FraryParticipant @malcolmfrary95515]

True enough, but it shouldn't take to much editorial effort to give the magazine reader, who paid good money for the magazine, the requisite clues to enable him to go out with a valid shopping list. The idea should be to encourage and inspire others to have a go, rather than to effectively say " I've done it, but I'm not quite going to tell you how "

The "CD motor" certainly does cover quite some ground, a dead CD player can yeild a relatively large one from the spindle drive, a smaller one from the tray drive and a small but useful one from the head drive, all of which can be driven in place of a standard servo motor. Unless one of them happens to be a 12 volt one, in which case you get a very slow boat.

As to plastic magic being difficult – after a suitable subject has been selected, it usually designs itself and has the great advantage for a clumsy git like me that somebody else has done the really hard work on the detail and basic structural accuracy. The borderline between "small working boat" and "magic" has shifted considerably over the past decade.

[Charles OatesParticipant @charlesoates31738]

Hi guys,

I think I'll have my tupence worth now. The original question was about motorising a small or plastic magic boat. I don't do plastic, but I have made six very small boats to sail on my garden pond, including the Terrier from the web site mentioned earlier.

Before I go on, I would urge any modeler to own and learn to use a simple multimeter. Being able to measure your amps milliamps and volts makes a whole lot of things easier.

When I started making these things I decided to use a striped down servo to provide the motor and speed control. I also had a box of salvaged tiny motors to possibly substitute for the servo motor. I did the obvious, and measured the current drawn by the original servo motor, and presumed that the servo maker had designed the electronics with this current in mind. I then checked each motor to see which might be suitable. Simples.

The upshot of all that is that mostly the original servo motor is best but with 1 exceptions For a tiny cargo boat, an old tape recorder motor was better, it draws the same current but has more torque and will turn a relatively bigger propeller and therefore sails better.

On the Terrier I used a cheap high torque servo with it,s original motor, built light and use a tiny 6 volt receiver supply. It doesn't quite plane but it's very nippy.

For all of these boats I make my own propellers as per the article in Model Boats. I think that is still somewhere on this site.

I'd recommend a garden pond boat to anyone, it'd a great way to relax in the evening.

Charlie

[Dodgy Geezer 1Participant @dodgygeezer1]

"…On the Terrier I used a cheap high torque servo with it,s original motor, built light and use a tiny 6 volt receiver supply. It doesn't quite plane but it's very nippy.…"

I don't suppose you have a photo, or, better still, a video of an R/C Terrier running? The EeZeBilt site would be very interested…

[Charles OatesParticipant @charlesoates31738]

Sorry Dodgy, I havn't got any pictures, I'm in the middle of a protracted house move / retirement.

I am still making things though, the move will take several months and I need my fix of model making so I'm making a 16 inch Zwarte Zee (ish) from one of the R A Sweet plans from model boats long long ago. Remember those? I loved them. This one has cassette motor and an old servo board running it.

As an aside, I built one of the Hobbies little tugs, and used a standard servo but with a pulley drive, about 3 to 1 so I could use the 1 inch 3 blade propeller. The model is about 16 inches, weighs over a killo and is still quite nippy. Sometimes a direct drive isn't the best option.

Love your web site, thanks.

Charles

[Dodgy Geezer 1Participant @dodgygeezer1]

Have you seen the Beaver tugs on the site? 12" with a pulley-drive )though at least one builder has doubled the size and gone for gears).

Here's a picture of a few, with one modified stern to become an AHV…

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