Powering a crane..

[PhilP]

Musing on a winter project..
One of the first items of rolling stock I bought was a Matra crane.. Since I bought it, I have mused on the idea of making it self-propelled, and working.

Am after the forum's collective wisdom on small motors/gearboxes. Whether servos would work with the stop removed (winch servos??) - do they 'hold' position? Ways of extending the boom..

On the boom front:
I have removed the long 'spring', and bit of plastic, from a disposable propelling pencil. This converts rotary motion to a linear action, and I reckon it would be adequate for extending the boom? I reckon it could be made to fit inside, and the 'end of travel' controlled with limit switches. Being a 'worm-type' arrangement, it should be possible to partially extend the boom and it hold.

I would not envisage lifting any great weight as the crane does not have any form of stabilisers on it. - something else to model / make work, perhaps.

Have thought of perhaps getting the Playmobil works-tractor with grab to see if any parts would be usable from that.

Any thoughts guys and galls?

Thanks,
PhilP.

 

[Madman]

I have found these miniature motors very valuable in modeling cranes and the like.  I`ve just completed a project on an LGB 2090 loco whereby I have remote control over it`s front coupler.  I have also posted a video of a crane I made some time ago using another variation of one of these motors.  They are on Evilbay and mostly from China and very reasonable.  The photos of the 2090 project will have to wait.  I will post a link to a video, which has yet to be produced.

http://www.ebay.com/itm/With-D-Shape-Short-Shaft-Miniature-Metal-Gear-Motors-12GA-3VDC-15r-min-/161096789702?pt=LH_DefaultDomain_0&hash=item25821deec6





http://youtu.be/1HGYIHZuoCA



Here is a photo of the motor, in position, in the 2090

 

[nicebutdim]

I converted a ToyTrain crane to RC. I used 3 mini servos converted to operate as geared motors and 3 micro speed controllers to operate them. The pulleys and blocks are from Cornwall Model Boats and the rest pretty much scratch built. Meccano came in useful for the worm drive for slewing and a Lazy Susan bearing is used between the crane and chassis.

 

[nicebutdim]

 

[nicebutdim]

 

[dunnyrail]

author=nicebutdim
Wow talk about clever. Wonder of you could post a Vid via YouTube to let us see it Operating?
JonD

 

[nicebutdim]

author=nicebutdim
Wow talk about clever. Wonder of you could post a Vid via YouTube to let us see it Operating?
JonD

Thank you, I'll give it a go, I have to find the transmitter and a battery pack. I'm trying to find a compact 5v rechargeable battery to power it as at the moment 4 aa cells sit on the counter weight on the back.

 

[DoctorM]

Someone posted this self propelled (courtesy of a 2090 Kof) Matra crane here on this forum a while back....

I kept the picture because it's a pretty impressive beast.

I had an old yellow 2060 Schoema in my spares box, and though I might copy the idea, but haven't yet got round to it.

 

[PhilP]

There are a number of these about..
Michael Adamson (GRS senior) built one, I believe. - did they make several??

I did ask if his was for sale.. It isn't, though I was allowed to take pictures. They are very impressive,it is almost impossible to see the join!

 

[Madman]

Someone posted this self propelled (courtesy of a 2090 Kof) Matra crane here on this forum a while back....

I kept the picture because it's a pretty impressive beast.

I had an old yellow 2060 Schoema in my spares box, and though I might copy the idea, but haven't yet got round to it.

Definitely will copy that. I really like the idea.

 

[gregh]

Must be the season for thinking about cranes. I have also been thinking/experimenting.

I had some ideas using servos, but then bought myself a 'toy' remote control crane for $20 like this:
http://www.dealsdirect.com.au/remote-control-giant-crane/
(I got mine at Aldi)

You should be able to find something like it in your neck of the woods, by searching for 'remote control toy crane'.
It rotates about 300deg and also raises and lowers the rope. I'll have to figure out how to use a servo to raise the jib for my model. The centre 'cab' houses the motors/gears and measures 115mm dia. so I should be able to mount it on a flat car.
In addition you get all those nice lattice 'girders' for use as part of the crane, or as loads, or as bridge pieces!

I did find another one (which I bought for my grandson) that has 3 actions - the 3rd one moves a carriage under the boom in and out.
http://www.toysrus.com.au/fast-lane-mega-crane-construction-set/

 

[Dtsteam]

Earwigo !

http://www.instructables.com/id/How-to-modify-a-servo-motor-for-continuous-rotatio/

This instructable is so detailed even my mum could do it.

 

[Dtsteam]

I think with this method he made a continuous running motor not a winch (forward and reverse).....

Ah yes, point taken. According to the comments in that post, there is a method of adding a couple of resistors to the servo circuit board to fool the feedback circuit into thinking its permanently at 90 degrees - you then send it a signal in either direction and it just keeps going until you send the value for 90 and then it stops.

Hmmm..... I'm now in the camp that says buy a sail winch :-\