[MOC/WiP] China Railways QJ with PF!

[LEGO Train 12 Volts]

... annnd here it is in the flesh!

Great project, great locomotive, great skills!

[Commander Wolf]

Thanks for your thoughts folks. Will try to post some video once I can clean it up a little more.

On 9/21/2015 at 2:02 AM, THERIZE said:

Cool! But I think you need to change the cables because well, you know it. But still it looks awesome!

Yeah, the wires definitely need to go. I need to get the LiPo battery before I can jam all the wiring into the locomotive itself, but hopefully soon.

On 9/21/2015 at 9:08 AM, legoman666 said:

Awesome. Any chance of getting the LDD file? Would love to make one of these.

I've attached the latest LDD file I had before going to build the real thing - it's probably 98% complete relative to the current state of the model, but it should be easy to figure out the last 2%. Like I said I've never tested the configuration with the LiPo battery (though the LDD file will tell you were it's supposed to go) so you'll have to see if that works.

Do post if you make one though, especially if you can improve on the design!

Edited January 18, 2019 by Commander Wolf

[zephyr1934]

Look at that beauty! Excellent work, even better in the brick than in the digital.

I was pretty replused by the BFBFB driver arrangement for a long time, but it looks a bit better in brick than in LDD and probably is more accurate in the end. This wheel arrangement still tracks more poorly than the fully articulated wheel arrangement though; the wide spacing between flanged wheels (idle and driver) tends to make all wheels more prone to picking switches, and even moreso the little guide channels in the switches.

Here's a little hack that I did to help my bigger engines through tiny switches (the black round plate+tile stacks between the rails, not the remote control switch lever)... and it is completely reversible too... it might help in your situation too. Go up one level from the image and you'll see it helped me on curves as well.

[THERIZE]

I just noticed something, your LDD model has 2 battery boxes. why?

[Meisterschnorrer]

Just wow...

I´m not able to build locos like this...

This is amazing...good work.

Regards

René

[BricksMcgee]

Truly breathtaking build. Any videos of the finished loco in action?

Brick on!

[Gabor]

What a beauty! Congratulations, very nice MOC!

[marbleman]

Hi, I'm from China. QJ is a very famous Chinese engine. I'm just design it now, your work give me good inspiration.

[Commander Wolf]

I just noticed something, your LDD model has 2 battery boxes. why?

The LDD model has two battery boxes because I ultimately wanted to have the entire power train in the locomotive itself, but I originally didn't have all the parts necessary to thoroughly test that configuration. I would consider this a feature though; you can choose to power it whichever way you like! I also originally had the idea of putting an old smoke generator in the engine and that probably would've needed a separate battery pack...

Truly breathtaking build. Any videos of the finished loco in action?

Brick on!

Yes! Finally got around to taking new pics and videos this weekend:

So yeah, here is the final, cleaned up and polished model:

It was actually a pain to configure it with the lipo battery and all the electronics in the loco. In my original design the receiver was literally half a stud too far forward for the cables from the motors to reach, but structural integrity issues prevented me from moving it any further back. Thus, I had to move it forward and jam a whole PF extender cable into the gap in order to bridge something like 2-3 studs worth of space. Super, super lame.

That being said, it's way more convenient to have the power functions contained exclusively in the loco, and you get rid of those goddamn cables. With the removal of the cables I tried to make some sort of cowling/flaps to fill the gap between the engine and the tender, but I couldn't make anything that worked.

Nonetheless, the placement of the battery box means that you can push on the rear of the dome assembly to power the loco on and off, a la the similar mechanism in set 60052 - also very convenient.

I was unable to reduce the gear ratio below 1:1, but I did manage to fix most of the switch/joint picking issues by moving making the 2nd axle the tired axle instead of the 4th and using a thin O-ring for traction. For reasons which are still not quite clear to me, the 2nd axle has better grip such that it doesn't need a fat O-ring, and the thin O-ring greatly helps keep it on the rails.

This unit is numbered as IAIS 7081, which is the least modified of the 3 QJs here in the US. I originally wanted to use the Avery 18865 labels that forum member dr_spock had recommended because they worked very well on my FM H10-44, but they don't seem to work well on dark base colors, so I had to keep using my tried and true but not-as-good 3M labels.

... and that's that for this project. There is a full gallery, but most of the pics have already been posted.

Have a nice day!

Hi, I'm from China. QJ is a very famous Chinese engine. I'm just design it now, your work give me good inspiration.

Looking forward to this one too; I didn't find any other Lego QJs before mine, so I'm curious to see what other people do.

[Sven J]

This is a truly great model of an impressive prototype. Thanks for sharing!

[zephyr1934]

A beautiful piece of work filled with mighty fine goodness... the interior packing of the PF is just another impressive feature.

[Man with a hat]

Very impressive work. Nice detailing. I like the front especially. And great job on fitting/cramping in all the PF.

[marbleman]

Looking forward to this one too; I didn't find any other Lego QJs before mine, so I'm curious to see what other people do.

http://tieba.baidu.com/p/3972193624，This isn't my MOC but from other Chinese Lego Fans. Just for your reference.

Edited October 16, 2015 by marbleman

[WholeWheatLego]

Hey marbleman, next time you quote a huge post, mind using a "<snip>" or two so we don't have to scroll forever to see your addition? Thanks!

Wow... amazing that you were able to have that many drivers with such minimal swing-out.

[dr_spock]

Great job! It's fun to watch it snake around curves.

[Peter_AU]

Hello , newbie here , am I able to get the plans for the QJ please