Power Pick-up Wheelset

[coaster]

Needed a break tonight from working on the tracks (which, if you haven't been following, you really should), so I put together a concept model of a power pick-up wheelset to basically jumper between 9V tracks and PF motors. This would sort of give us the best of both worlds in that there are no batteries needed, but you still have independent control of the trains, or you could keep it rail dependent if you wanted.

Before I get too carried away, would this be usable to the community?

[Cale]

Before I get too carried away, would this be usable to the community?

For those who build using the standard LEGO wheel set style yes.

For those of us that don't? Maybe not so much.

Bettendorf Josh Sanders Version by Cale Leiphart, on Flickr

Arch Bar Truck by Cale Leiphart, on Flickr

B&O Em1 19 by Cale Leiphart, on Flickr

IMG_2261 by Cale Leiphart, on Flickr

IMG_7299 by Cale Leiphart, on Flickr

WM Challenger 18 by Cale Leiphart, on Flickr

I think you can start to see the scale of the issue. At least for those of us who build at the upper end of detail.

Cale

[John Hill]

I think this would be very useful in the way you suggest but I use DCC and if I had one of these I would use to to pick up track power for passenger car car lights. I would also use your device to power 12V motors that I now use with DCC and very unsatisfactory wire brush pickups.

There are several ways this could be useful to the community, in my opinion.

[ScotNick]

I like what you did with the wheelset, but I think many (including me) would need wheels that fit on a cross-axle.

Maybe a pair of metal wheels that fit on a cross axle (spoked would look better IMO) and a 2x4 plate or similar that has the PF comnector and the power pick-ups to the wheels.

I think a big problem wih the wheelset that you have right now is that only the flange is made out of metal which could cause some problems with connectivity as the flange doesn't always touch the tracks (the 9V-motor's flanges have a spring that presses the metal to the tracks.

[legoman666]

Ive tried using power pickups on wheelsets that were not powered by a motor. If they pick up from the top of the track they have 1 major problem, they never slip, which means they get dirty. I'm talking in like 30-40 minutes so dirty that they don't function.

[coaster]

It probably isn't clear, but these aren't solid metal wheels. They're 2 pieces, with the flange being metal and spring loaded, identical to the 9V motor. Pick up is from the side, so aside from the small breaks in switches and crosses, they'll always stay in contact with the rails.

[Barduck]

It probably isn't clear, but these aren't solid metal wheels. They're 2 pieces, with the flange being metal and spring loaded, identical to the 9V motor. Pick up is from the side, so aside from the small breaks in switches and crosses, they'll always stay in contact with the rails.

So, in other words, if you'd use 2 of these you really shouldn't have any problems with power falling down.

As with your switches, I'd take a dozen

[Elektrychka]

I think this would be very useful in the way you suggest but I use DCC and if I had one of these I would use to to pick up track power for passenger car car lights. I would also use your device to power 12V motors that I now use with DCC and very unsatisfactory wire brush pickups.

There are several ways this could be useful to the community, in my opinion.

Use one wheelset for PF motor + IR receiver (can control motor power) and second one for lights (no control, just switched on power on tracks and lights lit up as well.

I think Lego could make this wheelset in 2007 instead of battery box. They made a big mistake, I think...

[Lego Dino 500]

Needed a break tonight from working on the tracks (which, if you haven't been following, you really should), so I put together a concept model of a power pick-up wheelset to basically jumper between 9V tracks and PF motors. This would sort of give us the best of both worlds in that there are no batteries needed, but you still have independent control of the trains, or you could keep it rail dependent if you wanted.

Before I get too carried away, would this be usable to the community?

These look really good. The problem is they're a bit too single-purposed, they won't work too well with any real sense of detail. Maybe if you got rid of the wheel covers, so it's a 4x3 shape in the center. Leave a 1 plate dip in the middle for the PF connector, and it'd be good. That'd give more potential for building small details, and make it versatile enough for various prototypes. With the PF connector that you picked, you could run this direct off the transformer like a DC model train, and if you add a Sbrick or IR receiver, you could set up a rudimentary DC system. That'd be awesome.

Edit: I just made a mockup of what it would look like in LDD, hope this helps.

You could maybe go without the top layer of studs for a thickness of 2 (3 with the axle/pickup mechanism), but then the PF connector would be higher than the brick.

Edited June 30, 2016 by Lego Dino 500

[Xris]

Hi,

a reliably working power pickup would be highly welcome.

I think your concept will be easier to implement than the other solutions favored by detail-oriented model builders.

Xris

[zephyr1934]

These look great! I personally have no problem with the lego style (if not actual lego?) wheel holder, though as per many earlier posts several folks would want to go without wheel holder. If it weren't too hard perhaps make it so that both mounting options are feasible. If not, I'm sure whoever is in the other camp will come around to the built form. It would be a nice option to run PF on 9v track w/o and IR receiver (or similar) and battery. Oh, one more thought, if it saves a lot of money, I suspect a pair of trucks each with a pickup on one side would also be a workable solution.

[JopieK]

One problem with power pickup is that LEGO is very light. I have had a colleague from the mechanical engineering department mill me some metal wheels. One can then use e.g. desoldering copper wire to pick it up. To make a reliable connection one will still need to add a lot of weight on the wheels especially if one would want to use DCC for example (that was my intent).

[dylanfarrow]

I'd order a box of those wheels!

[Rail Co]

I did try something similar in 2012 with the 7938 Red passenger train. As JopieK said the train is very light so it's hard to make good contact with the rails. Mine works "alright" but it stutters a lot and the wheels get dirt fast.

2012 MOD: 7938 Metal Wheels by Rail Co, on Flickr

But it does replace the battery box. If you can get the design to reliably work go for it but in my experience it isn't easy!

Cool concept though! I would buy

-RailCo

[coaster]

I'll build a few, see how it works.

[zephyr1934]

I had not noticed where you put the power output, a clever spot, but I THINK putting a PF connector on top would interfere with putting plates or a bogie plate above.

Meanwhile, RailCo's design is how I would have done it and had contemplating suggesting to you, i.e., put only one pickup wheel per axle. But with your design, by picking up both wheels if you used a pair of the pickups for a truck you might just be able to maintain contact with both rails.

[coaster]

You're right, I keep thinking the PF connector is like the old 9V one where you build on top of it. I should have room though to drop it down by a plate, which would eliminate that issue. And failing in that, I can always go back to the 9V connector.

I understand the concerns about maintaining contact. It'll be ok though. The flanges are spring loaded, like the old 9V motors, so the flanges are always in a compressed state against both rails. The problem with the solid wheels is the wheelset still floats between the rails, so you are always relying on only top contact on one wheel, which we know isn't reliable.

[Lazarus]

I use a setup close to Rail Co

But i use bushes to take the power direct from the wheel and not from the bar i isolate the bar so i can pickup power from both sides on a single bogie.

but with only a single wheel set running it does lose contact as the train moves. to run this idea well you need to have two wheel sets just like the 9v motor to maximize the contact on the rail.

But other than that this is the next step to running 9v in 2016 with the decline in 9v motors around and the price.

[Redimus]

I really like the idea, but would it not be easier to use the 9v style of power transfer? It would allow the much less invasive 9v system on the bogie, which can easily be transferred to the more modern wiring in the train it's self using the pf wire that is explicitly designed to transfer between the two systems.

Also I feel if you're gonna have metal wheels, you need all of them being metal, seeing noticeably different wheels on the same bogie is a real put off for me.

Edited July 4, 2016 by Redimus

[coaster]

After considering it further, Redimus, I'm of the same mind moving back to the 9V setup. I can leave the plate height the same, and it's easier then to gang two of these together on a bogie. And I imagined most folks would use 2 of these per bogie, but keeping them as single self-contained units allows for variable wheel spacing.

[Lego Dino 500]

After considering it further, Redimus, I'm of the same mind moving back to the 9V setup. I can leave the plate height the same, and it's easier then to gang two of these together on a bogie. And I imagined most folks would use 2 of these per bogie, but keeping them as single self-contained units allows for variable wheel spacing.

That's a good idea. With them separate like that, you can also use the default bogies and wheel covers like from the 9V and PF motors.

[ukewarrior]

So... did this idea die?   It really is needed given the state of 9v motor availability.

[coaster]

Nope, not dead at all.  I work on it in between track prototypes, but unfortunately, the tracks have been taking up all my spare time lately.  I've got this mostly figured out, there's just a few housing issues to resolve.  I'd post an update picture, but the assembly is currently mid-revision and looks like trash.  Once I get it cleaned up I'll post it.

[Lego Dino 500]

That's cool, I've had this project of yours in the back of my head the last few months. Do the electronics allow you to use this as a power source in lieu of a battery? You could set up a pretty decent DCC system using a couple of these and some Bricks. 

Edited November 8, 2016 by Lego Dino 500

[coaster]

I don't see why not.  I'm a mechanical guy, not electrical, but as far as I can tell the IR reciever or motor should be blind to the actual source, so long as they see 9V.