Powered Trucks for Split Train Base

[roamingstop]

For a MOC I am working on, I decided to try to use the split level train bases with a custom made truck / bogey which could be powered by a PF-M motor. Ive put together a couple of designs, but find that the train wheels consistently slip even when boat weights are added.

As mentioned in other threads, fitting gearing mechanisms into the truck is not easy; so the solution currently only has one powered axle (the other is dummy) which probably does not help the traction. Does anyone have any suggestions?

LXF file.

I know of a solution which uses the standard RC / 9V (but not PF) motors, but this makes the base even longer (by another 2 studs from above image). In tests the RC / 9V motor combination has no slipping problems, and actually runs faster than with the PF-M motor... which I should probably live with. It is just going around Lego curves the massive overhang of the extra long bodywork is a bit of a pity.

The other way is to power both axles (or build a 3 axle truck) but this starts getting pretty big when compared to other Lego scales. What suggestions do others have?

[ZueriHB]

To stick with the brick built bogies:

Change to the new train wheels with clear rubber O-rings and motorize more than one axle, if you're unable to motorize both in one bogie, motorize a second bogie for more traction. May that helps.

[Shupp]

My honest suggestion is to avoid using one piece train bases when you can. It severely limits how you can attach your motors. In general, having only one powered axle just doesn't work very well, and to power more axles you really need to attach the motor in the middle of the truck rather than over one end, which it doesn't look like you can do with that train base. Is there maybe a solution to get that same body shape using 6087 for extra strength? Not using the train base lets you get the exact length you want, as well, if you're worried about overhang.

[roamingstop]

I completely agree with you Shupp... but sometimes the challenge of using KFOL suitable pieces is more fun!.

I rearranged axles again last night - but the main issue is the vertical axle needs to be 1 stud offset (maximum) from the horizontal axle, otherwise the truck will never turn inside the wheel arch. I think I will return back to the RC / 9V motor solution as it allows good turning without too much overhang... and the vertical space for the motor is reduced.

[roamingstop]

As a little update; my Lego branded rubber bands arrived last night. This allows the front axles to also be driven from the rear axle (with 1/2 width bushes). It improves the drive performance; but it is still regularly slipping and using custom base plates probably makes the most sense.

A good design exercise.

[Sokratesz]

I think it would be possible to drive both bogies with a single motor there?

[ZueriHB]

I tried myself at this challenge too.

I started with the same approach as used with the 4559 Cargo Railway, but after adding a second split-level base, it didn't really work very well. the cable is in the way, I found no way of securing everything on the connector side of the RC motor, even using electrical plates.

So I tried again with a PF motor:

Just mind the cable, but it's less a hassle as with a 9V or RC motor, just get it out sideways, so it won't get crushed or clipped between the split-level base and the PF motor.

It also handles the LEGO radi without problems, and just looks good:

[roamingstop]

Hi ZuriHB

This is exactly the choice I too made for the split level design, the LXF file (above) shows the same concept for a front Locomotive only. It is somewhat easier with the tile + pin connection if you use the older RC / 9V motor, but obviously PF does work as well. Did you try feeding the PF cable through the body of the split base?

I think it is clear to assume that a mechanical powered solution can work, but for small MOC's only, and a proper Lego Motor is better for everything else.

Oh and thanks for the info on the 4559 solution. I did not realise how they assembled their train as I never really liked the colour scheme (or play factors). I had done a variant where the yellow 2x2 round plates are using 2x2 turntables; it works well but is just not so KFOL friendly (for AFOL it works fine).

Edited August 9, 2011 by roamingstudio

[Sokratesz]

I don't own any of those train bases but I would like to see a solution that powers both bogies, of course this will lose the ability to place any normal loads on it because of the axle you'll need..

- Sok.

[roamingstop]

I would like to see a solution that powers both bogies

Yep. Me too... using a rubber band two connect the two axles is the only solution I have found which fits inside the small base and looks good. Any larger diameter cogs / gears will obstruct passage through RC / 9V era points.

One solution which might work I saw posted on Railbricks; and that is to use 1/2 width technic beams, and a collection of small 8t gears (along the outside of truck) which can be used to power the second axle. However the small 8t gears obstruct the 12T bevel necessary to transfer the vertical drive shaft.

Perhaps this part has a smaller diameter for the 8t?

Edited August 9, 2011 by roamingstudio

[ZueriHB]

Hi ZuriHB

This is exactly the choice I too made for the split level design, the LXF file (above) shows the same concept for a front Locomotive only. It is somewhat easier with the tile + pin connection if you use the older RC / 9V motor, but obviously PF does work as well. Did you try feeding the PF cable through the body of the split base?

I think it is clear to assume that a mechanical powered solution can work, but for small MOC's only, and a proper Lego Motor is better for everything else.

Oh and thanks for the info on the 4559 solution. I did not realise how they assembled their train as I never really liked the colour scheme (or play factors). I had done a variant where the yellow 2x2 round plates are using 2x2 turntables; it works well but is just not so KFOL friendly (for AFOL it works fine).

I just love my two 4559's, here a better shot of TLG's solution:

I didn't thought of that, so I rerouted the cable trough the gap in the split-level base:

looks way better.

If you try TLG's or any other solution with standard train motors and the split-level base, you'll need to increase the height of the bogies by one plate.

Also, add some bricks to the motor or split-level base to shrink the gap between them (add max. 2 knobs total).

Yep. Me too... using a rubber band two connect the two axles is the only solution I have found which fits inside the small base and looks good. Any larger diameter cogs / gears will obstruct passage through RC / 9V era points.

One solution which might work I saw posted on Railbricks; and that is to use 1/2 width technic beams, and a collection of small 8t gears (along the outside of truck) which can be used to power the second axle. However the small 8t gears obstruct the 12T bevel necessary to transfer the vertical drive shaft.

Perhaps this part has a smaller diameter for the 8t?

I first tried that method for my FLIRT MOC, but alas, my MOC is everything but complete, so never built and tested. But my KFOL Technic days teach me one thing: small gears generate more friction than big ones, and lot's of small gears are hard to turn.

But I wish you luck.

[Snapshot]

Yep. Me too... using a rubber band two connect the two axles is the only solution I have found which fits inside the small base and looks good. Any larger diameter cogs / gears will obstruct passage through RC / 9V era points.

One solution which might work I saw posted on Railbricks; and that is to use 1/2 width technic beams, and a collection of small 8t gears (along the outside of truck) which can be used to power the second axle. However the small 8t gears obstruct the 12T bevel necessary to transfer the vertical drive shaft.

Perhaps this part has a smaller diameter for the 8t?

Have a look at this method for powering a second set of wheels. It's a truly wonderful little model anyway.....