5V model railway

[Bilton Junction]

Thank you Ted. That is very helpful. I was thinking about converting a Bachman deltic to RC using a voltage booster and retaining the original 12v motor. The problem is that the motor and cardan shafts take up a lot of space within the body which has thick mazac walls, leaving little space for a battery. There is an additional mazac weight in the fuel tanks which offers the largest potential space for a battery but removing that will affect the centre of gravity. I thought instead, it may be better to use two Minebea 5v motors which would provide, hopefully a similar level of power and mounting them to drive the bogies directly. That would free up a lot of space for a battery/batteries and if it is necessary to provide more space to allow the separate motors to swing it would be better to cut off equal amounts of mazac at each end to avoid unbalancing the body. Your advice about connecting additional batteries and the use of the higher power receiver answers my other questions, that I didn't ask, but was also concerned about!
Carl

[Will L]

...There is an additional mazac weight in the fuel tanks which offers the largest potential space for a battery but removing that will affect the centre of gravity. ...

Actually, probably not, given the fuel tanks are central under the body, you should be able to empty them of weight while retraining the CofG central, depending on exactly where the weight is. That is assuming you can afford to loose the weight and still pull enough.

The CofG location affects the balance of the loco. The absolute weight affects how much it will pull, but getting the CofG it in the wrong place will reduce the amount you can pull with a given weight of loco. The father from the current CofG you add or remove weight, the bigger the impact on the CofG will be. So 10 gram 1cm from the CofG has the same impact as 1gm at 10cm.

[zebedeesknees]

Thank you Ted. That is very helpful. I was thinking about converting a Bachman deltic to RC using a voltage booster and retaining the original 12v motor.

Hi Carl, I am currently intermittently in the throes of this with an early Bachmann 37. Keeping as much as possible of the original seems to me to be the most practical and quick. On the other hand, the Penbits bogies are slowing me somewhat!

The problem is that the motor and cardan shafts take up a lot of space within the body which has thick mazac walls, leaving little space for a battery.

I wonder what physical size of battery you are planning for. And then what capacity. Of course the recharge arrangements will affect that.

There is an additional mazac weight in the fuel tanks which offers the largest potential space for a battery but removing that will affect the centre of gravity.

I don't have a Deltic, but believe the 37 to be very similar; my tank weight was 88g, not enough to affect the body roll on curves imo, and certainly not with the original rigid bogies. With a little carving of plastic, I have installed two 200mAh batteries in the tanks space, which should in theory give the best part of an hour of full speed running between charges.

I thought instead, it may be better to use two Minebea 5v motors which would provide, hopefully a similar level of power and mounting them to drive the bogies directly. That would free up a lot of space for a battery/batteries and if it is necessary to provide more space to allow the separate motors to swing it would be better to cut off equal amounts of mazac at each end to avoid unbalancing the body.

That is an alternative route, and I wouldn't want to dissuade you from this interesting project. I do think that if the Deltic has as much space under the roof as the 37, there should be room for enough battery power and other components to enable the original motor and drive to be retained.

Your advice about connecting additional batteries and the use of the higher power receiver answers my other questions, that I didn't ask, but was also concerned about!

Ahhh well, I have been down these roads for a while now. The next big question is how to recharge the battery(s). My thoughts on this are still evolving, and others may yet come up with alternative and better ideas than mine. So far, I have two versions, both using existing wheel pickups, but neither relying on them for drive continuity. The first uses any voltage across the rails but needs conditioning circuits within the loco (space!), the second uses only tiny components but a single pole refuelling connection. Some of this should be made clearer in an article in the next Scalefour News...237.

Ted.

[Bilton Junction]

Will, I was not thinking of the fore and aft C of G but of the vertical component. It did run fairly well with just drop in wheel sets. The bogies pivot at the top of the body, so the weight is all below, but I suspect that if I remove weight from the below-floor fuel tanks it will move the C of G too high and it may cause it to loll about or wobble when moving.

[Bilton Junction]

Thank you Ted. It does seem preferable to do the minimum conversion possible. I was looking to install the battery in the narrow space to the sides of the cardan shafts, (7mm at best in the deltic). It would be possible, but potentially a problem with the wires becoming entangled. There is not much between a Bachman 37 and 55 and if it wouldn't affect things that much using the space in the fuel tanks for the battery (even half an hour or less between charges would be quite adequate for me) and keeping the original motor and flywheels does seem a far better option.

I await the next MRJ with interest. I have dusted off my nascent railway in the loft quite a few times over the last few years and the main problem has always been track power, DCC was not the answer to that, indeed it creates more problems than it solves. RC is potentially a great step forward.
Carl