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Stumbled onto this by accident! What a great concept. I have already bought a cheap RC toy car with the idea of butchering the chassis from it into a diecast 1:43 Morris Oxford or similar. Not sure if the weight of the diecast model would overpower the toy motor though. Worth a try just for a laugh really.

 

Keep this thread going - I am currently building a small Gn15 diorama and I have 1:24 Bedfords I could use for RC - that would be a neat trick for shows!

 

Let us know what you use for control - I am completely hopeless at electronics but want my layouts to have more interest than just an occasional locomotive movement. Now that we have the beautifully detailed rolling stock I think it is about time we had equally realistic road scenes to complement.

 

Thanks - like you, it's a wish to have a little more realistic movement around the scene (....but certainly realistic!), and like you, I'm not an electronics whizz..., but it'll be fun if we can pull it off.

I'm not anticipating any real trouble driving the rear axle (famous last words - after all, one can approach it in the same way or similar way as locos. There are lots of miniature ball bearings available on e-bay, which helps a great deal, so the difficult thing is the steering axle - which I think I've cracked now, and putting together a package of teeny radio control bits. I've found that conventional servos go down to 2.5 grammes, - I've got a 3.7g to steer this, and the 2.5g is a little smaller (not very much, but every little helps) - but I'm still untangling the rest of the kit.......

 

Meanwhilst, track rod is on. The wiggle is deliberate, as allows for adjustment of tracking (which a straight one with fixed ends doesn't). The loop at one end is to take the steering link from the servo - which drops down through the big hole in the floor.

 

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This is simply brilliant! It's also a real eye-opener as to what's available to make this sort of thing work. I expect this sort of radio control could be applied to a loco and small industrial shunting layout - properly rusty and rickety track, even on the rail tops...

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I just lurk in the background waiting to see how this all shapes up. I am waiting for the breakdown of the parts used as I would really love to apply this technology to both my 1:43 layout (diecast road vehicles) and my 1:24 layout (the Emhar 1:24 Bedford truck).

 

Keep going!

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  • 2 weeks later...

I've added the steering servo - since they're only £6 a go, I've araldited it in place, and if it fails, I'll simply break it out and replace it. In this location it sits where the dashboard goes. This is the 3.7 gram servo, but you can get a 2.8 gram (I think it is) which is fractionally smaller (I would get this next time...) and this may fit under the bonnet longitudinally, which the 3.7g won't.

I've committed to getting a sub miniature combined receiver/speedcontroller - the 'Minor Tiny' made by MicroInvent which is only 17mm x 8mm x 4mm !!!!! This provides forward and reverse, proportional steering and speed control, and I think, even a facility for brake lights! Its not cheap at around £75 or so, but if it makes an interesting model, I'm up for it....

There are some LiPo batteries whichwould fit under the bonnet, together with the receiver/speed controller, leaving only the motor hanging out....

 

Delivery will take a bit of time, so there will doubless be a pause!

 

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Just a couple of thoughts. Instead of building a box body use the original body and add a tilt. This will also have the advantage of easy access to the works. If you are still having problems with building a differential have you considered using a separate motor for each wheel? this was used sometimes on full sized trolleybuses, the motors automatically adjust their speed.

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Just to stir the pot - http://www.cheapcontrolsystems.com/

 

Uses a PS2 controller for control of your RC vehicle with up to six servos.

 

Useful?

 

 

Quite brilliant - and should be extremely useful somewhere down the line. I can see this would be perfect for motorising a digger or a crane - for instance.......

 

I'm now committed to the Minor Tiny, which I think is probably the smallest - and therefore suits me best for this particular job (it's on order). This cheapcontrolsystems doesn't appear to give a size - but I think it's a little bigger. Perfect for operating multiple servos! biggrin.gif

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Just a couple of thoughts. Instead of building a box body use the original body and add a tilt. This will also have the advantage of easy access to the works. If you are still having problems with building a differential have you considered using a separate motor for each wheel? this was used sometimes on full sized trolleybuses, the motors automatically adjust their speed.

 

 

I want to try really hard to get the drive under the load bed so I don't have any body at all (it leaves the way clear for all sorts of fun!), but if I can't manage it, it's certainly an idea.....

 

Very nice idea about the dual motors - a very sound principle - but I'm struggling to fit one motor/drive at the moment. I'm looking for a scale 15 - 20 mph @ around 4 volts, wheel diameter 18.3mm biggrin.gif

 

PS Cab is blue now, and starting to look much more '50s

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Just changing the appearance..... You can just see the servo arm underneath, in the first picture. (rather cruel to photo this close up on something that really isn't very big....sad.gif )

 

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Yes it does look very good but.

 

Where are you putting the traction drive motor and the battery?

 

Pete

 

I'm planning on the motor/ gearbox going underneath the load-bed, running forward into the back of the cab (at low level) driving through bevel gears. The battery I think will either fit sideways inside the cab - or just underneath the load bed, above the motor.... I really want to avoid havingg to carry a dummy load or any thing!

 

Giles

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I have built a few toys for the kids using a servo as the drive motor. A pair of 680R resistors in place of the position pot and remove the rotation stops will give you a nicely gear motor package all ready to connect directly to the receiver.

 

 

Yes, I gather you can do that - indeed Technobots sell a continuous rotating servo - which I presume is basically the sames beast. Very useful.

 

I'm just amazed at what you can buy nowadays - and therefore what one might be able to put together, given time, patience and good eyesight!

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This is the sort of thing that can be done....

 

 

if you really get into it...... very impressive indeed! But the object of this exercise is to see if Mr average can do it with more or less of the self stuff and railway modelling capability..... (so far, the only possible exception to that is I've used a small lathe to make up the front hubs, but that was actually a very easy exercise, and I think it might be possible to do it without by using miniature flanges bearings if one can find appropriate sizes washers to open up......)

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This is the sort of thing that can be done....

 

 

if you really get into it...... very impressive indeed! But the object of this exercise is to see if Mr average can do it with more or less of the self stuff and railway modelling capability..... (so far, the only possible exception to that is I've used a small lathe to make up the front hubs, but that was actually a very easy exercise, and I think it might be possible to do it without by using miniature flanges bearings if one can find appropriate sizes washers to open up......)

 

 

And, oh my, even the 2mm(-ish) chaps are at it:

 

 

Impressed...

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OK Giles I said I was a licorice incompetent! In the last photo you show two motors - what is the second motor for?

 

By the look of it the battery would easily fit between the back axle and the rear number plate.

 

Just can't wait to see this one running.

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OK Giles I said I was a licorice incompetent! In the last photo you show two motors - what is the second motor for?

 

By the look of it the battery would easily fit between the back axle and the rear number plate.

 

Just can't wait to see this one running.

 

 

....just seeing if you were paying attention, Ian! The second motor is a slightly different ratio, giving different road speeds - just in case... At 3.7 volts, I reckon one will give me about 18mph, and the other will give me about 10mph flat out... (I don't think I want racing cars, anyway). If one is pootling arount country lanes and reversing into yards, I think speeds of this order are more useful.

 

A heads-up, a Canadian company producing some of these motor/gearboxes has stopped production, so Technobots, for instance, are running out.

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The motors came from autofocus video camera lenses, a role taken over by linear stepper motors now, so the market disappeared. Techobots are not the only supplier and quantities exist at the moment on the surplus market, but as time goes on..........

 

The gearboxes are very good, the motors very reasonable, they can be replaced with coreless motors on some designs, but I found the motors fitted could deliver lots of power anyway due to the gear ratio. Generally very quite, unless revved up hard!!

 

Slightly larger versions with epicyclic gear boxes are still available, in production, it is the tiny motored versions that are going to get more difficult to source in future.

 

Stephen.

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Mounting the motor couldn't be easier - I wrapped it in cling film (1 layer!), and then bedded it down in milliput (in the correct position, of course...)

 

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Making very sure of two things.

 

First, that the shaft lines up exactly with the back axle (which is easy to do by eye - sighting it through), and secondly, that the milliput is shaped to allow the motor to lift out - i.e. you don't bring it all the way round the curve of the motor.....

 

 

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Given the long setting time, it's very easy to get all this sorted satisfactorally. The motor can later be permanently fixed with a strap or even adhesive, if I'm brave!

 

 

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A snails view (which no one will really see) of the motor/gearbox. When things are painted black it won't be so bad. (there's a silencer to go across here somewhere, as well...)

 

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A much more genuine view. On future models, it would be possible to arrange things to have the motor under the bonnet and a shaft to the back axle, if required......

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Please sir can I have one? In red please, they go faster!!!!

 

Looking better all the time. I agree that as a future mod, you could mount the motor under the bonnet.

 

This must be close to actually running now? It all seemed so easy too - or is it all in the story telling?

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