MattWallace Posted September 24, 2012 Share Posted September 24, 2012 Hi all, I've been thinking about how I might go about motorising a container crane for my OO gauge container depot without going to the expense of trying to track down a Heljan Container Crane. My current thoughts are to either: 1) mount a scale-scenes crane on a tenshodo spud or similar (admittedly I've not measured this to see if it would fit!) for "X" with two more small motors for pulley "Y" and cable "Z" mounted inside the cab 2) see if I can some-how automate https://railsofsheffield.com/traversing-crane-546-JJJA17660.aspx I am assuming that I need to have some (very) small motors for the "Y" and "Z" axis and was wondering if people here might be able to suggest some options for me? As far as Driving the motors is concerned, I have found out recently that you can convert an Arduino into a DCC Decoder so I would probably find a way of mounting an arduino teensy (http://www.pjrc.com/store/teensypp.html) or similar to control them (again, assuming that running three motors form a 4-function DCC decoder is not an option). DCC aside, I would still welcome ideas on how to get this running without DCC if that is an issue! Thanks in advance, Matt Link to post Share on other sites More sharing options...
relaxinghobby Posted October 7, 2012 Share Posted October 7, 2012 The Ratio Travelling crane looks like a stationary one, the one in the link to Rails of Sheffield. If so you could mount the motors and thier gearboxes under the layout and move the crane with thread on cable drums turned by the motors. This would enable you to use the motor and gearbox kits from Maplins Electronics which allows you to try different gear ratios. I am not familiar with what the Arduino is so can not visualise how big it is. I've just googled it and it's an electronic control board. Why not buy and assemble the Ratio crane kit and see it you can make it move just by attaching cotton thread to it, then make guides to run the thread under the base board or into a building next to the crane that is big enough to hide the motors and winding gear? Then develope the electronic control control of the motors. A step by step development. Link to post Share on other sites More sharing options...
relaxinghobby Posted October 7, 2012 Share Posted October 7, 2012 I can't stop thinking about it. Here is the photo from the Ratio Catalogue, I'm sure they won't mind us using it if it means someone is going to buy one In the left hand photo the black string is to lower the hook. The red string is to traverse the crane, the motor winds one way and the weight or spring pulls it back. It will have work mechanically satisfactorily before it will can be motorised. Any one with any ideas? Link to post Share on other sites More sharing options...
Kenton Posted October 7, 2012 Share Posted October 7, 2012 relaxinghobby, I'd be a bit worried over the potential issue of friction without some pulley/wheel on the top corner and the forces of pulling would naturally lead to the crane tipping about that corner. Though the opposite side could be fixed. As far as motors are concerned there are some pretty tiny ones used in Z gauge locos - but the problem with any motor is getting it to mesh with suitable gearing. Link to post Share on other sites More sharing options...
MattWallace Posted October 15, 2012 Author Share Posted October 15, 2012 Thanks both, these are great comments, my brain is still slowley processing this idea in the back of my mind.... Link to post Share on other sites More sharing options...
RMweb Gold 96701 Posted October 18, 2012 RMweb Gold Share Posted October 18, 2012 The problem with thread is that it twists (wire ropes are put together such that they don't twist). Using thread on the six fall block could result in a tangled mess, so I would try monofilament first.. Link to post Share on other sites More sharing options...
shortliner Posted October 18, 2012 Share Posted October 18, 2012 Biggest problem will be the hook - small motors, look for pager motors on ebay and internet Link to post Share on other sites More sharing options...
Pugsley Posted October 18, 2012 Share Posted October 18, 2012 The problem with thread is that it twists (wire ropes are put together such that they don't twist). Using thread on the six fall block could result in a tangled mess, so I would try monofilament first.. Another option is stainless steel microbraid from Eileens (0.31mm is the smallest diameter), which is miniature steel rope. Link to post Share on other sites More sharing options...
Bruciethefish Posted October 28, 2012 Share Posted October 28, 2012 Some very small motors & gears contained in miniature servos, designed for model helicopters.. Might be a useful source of experimentation.... Link to post Share on other sites More sharing options...
Horsetan Posted October 29, 2012 Share Posted October 29, 2012 In 2mm FS, I think there's a modeller named John Greenwood (?), who built and occasionally exhibits a layout called "Wenfordbridge", based on those well-known lines around Bodmin. On his layout is a tiny gantry crane, much like that in post no.3 above. It works - the thing slides from side to side, and the pulley and hook goes up and down. Magic. Question is: how did he do it? Link to post Share on other sites More sharing options...
Removed a/c Posted October 29, 2012 Share Posted October 29, 2012 What about the motors in T Gauge locos? Link to post Share on other sites More sharing options...
ozzyo Posted November 3, 2012 Share Posted November 3, 2012 I can't stop thinking about it. Here is the photo from the Ratio Catalogue, I'm sure they won't mind us using it if it means someone is going to buy one In the left hand photo the black string is to lower the hook. The red string is to traverse the crane, the motor winds one way and the weight or spring pulls it back. It will have work mechanically satisfactorily before it will can be motorised. Any one with any ideas? One of the problems with motorising the crane like this is when you traverse the winding house, the hook will go up or down as well. So it would be better of you could get the winding gear into the winding house. It's more work but I would think that a four function decoder would do it. Two for in and out and two for up and down. One more thing to think about is the amount of weight that will be needed in the hook block as well. If your going to do it right you will want about a four to one pulley set up, also each wheel should be independent as well. The more wheels on the pulleys the better the lifting ratio, so if you have a 4;1 ratio between the motor and winding drum and a 4;1 ratio on the lifting block (hook) you end up with a 16;1 ratio? To build a proper set of windings for a crane is not as easy as it first looks. OzzyO. PS. if the layout is to be transportable you would be as well to think about somewhere to anchor the hook for when you move the layout. Link to post Share on other sites More sharing options...
MattWallace Posted November 3, 2012 Author Share Posted November 3, 2012 I'm starting to think that a scratch built crane may be the way to go (or even drop the idea of a crane completely and have it as a small marshalling yard!), that way I would have control over the pullys etc. Matt Link to post Share on other sites More sharing options...
Giles Posted November 6, 2012 Share Posted November 6, 2012 this is probably what you want as far as motor/gearbox for the winch is concerned. A variety of ratios available, 6v or 12v, overall length about 22mm, (x 10mm or so) available from Precision Microdrives by The Oval, in London. (Canterbury Court). You can also pick them up (or similar) on EBay. I used one in my RC truck. Link to post Share on other sites More sharing options...
MattWallace Posted November 6, 2012 Author Share Posted November 6, 2012 Thanks Giles, I've ordered a few things from PMD before, I'll check this out as an option. I'm thinking that my best bet may be to use an Arduino as the "decoder" and then wire my own motors etc. Matt Link to post Share on other sites More sharing options...
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