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Finally getting around to posting some of these... I've been doing a bunch of small projects this year that I don't feel warranty their own thread, so this thread is going to be a home for said small projects.

PRR MP54

Some years ago I built a set of PRR P54 coaches to go with my PRR T1. At the time I thought a fun future project would be to convert the cars to MP54 spec - the EMU version of the same car. Well, the future is now!

Over the past few years I've been trying to build trains using all of various the LEGO motors, and the PF train motor was still on my hit list. I don't like the PF train motor that much because it doesn't have any low-speed torque, and the wheel spacing hasn't been correct for anything I've made so far. Recently I remembered about the MP54, and I thought it would be the perfect application - fast and doesn't need a lot of torque.

Here is one of the original P54s as built:

cam05859.jpg

And here is the MP54 conversion:

170724_mp54_2.jpg

Of course the main difference is that there is a battery box, receiver, and motor in the MP54, but I've also updated the original model over the years, most noticeably by slowly collecting all the frames and glass.

Other minor changes include the addition of headlights and a more vanilla bogie design to match the PF motor frames.

170724_mp54_3.jpg

170724_mp54_4.jpg

Of course you want to see it go:

I was really entertained by how fast it goes! Usually I prefer gearing down such that you get more torque and less speed, but watching this zip along is a fun change of pace. The pulling power isn't actually all that bad either, but as expected, you need to be going pretty fast before the PF train motor is generating any torque.

One more interesting thing is that I'm actually using BBB wheels on the PF motor instead of the usual tyred wheels. I originally tried with the official wheels, but I due to the low torque I felt like it was really bogging down in the corners, so I tried the BBBs. This is a much smoother configuration, and it doesn't feel like I'm losing all that much grip. It can definitely pull at least the other two P54s and maybe another car or two.

Okay, more to come soon. Hopefully.

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Looks great! You wouldn't happen to be from LI? I love seeing my hometown railroad get some representation. 

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Great to see the T1 again (I still think it is a fantastic build), and it is neat to see all of the improvements you've made in the conversion to MP54, it is amazing what the 1x2x2 windows do for the look. Great MOC!

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5 hours ago, Paddyb98 said:

Looks great! You wouldn't happen to be from LI? I love seeing my hometown railroad get some representation. 

 

Ha ha, sadly no, I'm from California. I built the P54/MP54s because they were contemporary to the T1 and short: longer passenger cars seemed like they'd be a little too awkward on R40 curves. It's somewhat by chance that they were also a PRR design, even though they would not have actually run with the T1.

 

3 hours ago, zephyr1934 said:

Great to see the T1 again (I still think it is a fantastic build), and it is neat to see all of the improvements you've made in the conversion to MP54, it is amazing what the 1x2x2 windows do for the look. Great MOC!

 

Thanks Zephyr! The T1 has also gotten a few upgrades over the years, though they are less drastic than those on the P54s. I'm actually looking at doing (better) PF drivetrains for my older unpowered locos, hopefully they will make a showing here if I can make them work!

 

Spoiler

img_0505.jpg

img_3522.jpg

 

 

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Side project number two:

GE U30B R2

In 2015 I built a Norfolk and Western U30B. This was dismantled not too long after in favor of other models, but now it's back!

A few many months ago, I was playing with some brick weathering schemes, and one of my samples was the U30. Reaction from various sources was fairly mixed, but in the end I decided that I needed to build something to see what the weathering really looked like. And thus the U30 came back.

Spoiler

u30b_9v_weathered_170329a.jpg

 

Some of the feedback I got did suggest that the weathering was too aggressive, so I did end up scaling it back before building:

Spoiler

u30b_9v_weathered_170627a.jpg

 

And here it is in all its weathered glory:

img_3715.jpg

img_3709.jpg

 

I actually think it's pretty darn good, but I still have mixed feelings about implementing similar weathering patterns across the board, but a big part of the experiment is to keep it around and see how I feel about it. I've brought it to a few local LUG meetings, and for better or for worse not too many people have commented on the weathering. People have commented on the sound: more on that in a bit.

img_3714.jpg

 

Fundamentally the build is the same as the last one, but I did make some small tweaks: the greebles on the bogies are a bit different, and I've used real flex tubing for the handrails. I also altered the drivetrain(s) within the bogies to use two short shafts rather than one long shaft. This is because the bogies flex a little, and one long shaft sees a ton more friction than two short shafts when the truck flexes under load.

Spoiler

More friction:

u30b_demo_150306b.png

 

Less friction:

img_3729.jpg

 

But the biggest change is actually in the rest of the drivetrain! This engine is powered by two of the old ungeared 9v Technic motors!

img_3727.jpg

 

This is actually the main reason I chose to implement weathering on this model as opposed to the other candidates. Like I said in the previous post, I'm on an informal mission to build trains using every practical motor - for fun and to explore the performance characteristics. 

img_3728.jpg

 

I originally built the U30 to accept multiple motors, but even then it was a little difficult to use the ungeared motor as it needed a second gear reduction stage. I originally wanted to make the first stage a belt drive (LEGO does this for all official implementations because it will be much smoother than gears), but I couldn't find the space. I may revisit this in the future, but for now the 1:3 reduction with the crown gear is hilarious, and almost makes a diesel sound at lower RPMs. 

  • 13s: low speed pass
  • 32s: top speed pass
  • 50s: heavier loads

 

I didn't look at the numbers again until after I had completed the model, but the power output of the old geared motors is actually comparable if not slightly higher than PF Ms. As such the performance is actually quite good: decent low speed torque, and the top speed isn't bad either. The second reduction stage could almost be 3:5 rather than 1:3, but these are all things to experiment on in the future.

Other pics of the old and new unit, whenever the gallery is moderated, but that's it for this mini-project. Til next time.

Edited by Commander Wolf

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These are looking very nice! 

On 11/2/2017 at 2:02 AM, Commander Wolf said:

Other minor changes include the addition of headlights and a more vanilla bogie design to match the PF motor frames.

You don't have to use the Lego motor frames with the PF motor, my GP-9 for example has built up sideframes for extra realism. 

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On 11/13/2017 at 5:27 PM, CrispyBassist said:

These are looking very nice! 

You don't have to use the Lego motor frames with the PF motor, my GP-9 for example has built up sideframes for extra realism. 

How are you attaching these to the motor itself?

I had played around with custom frames on 9v motors some time ago, but forming a sufficiently strong connection with the motor brick made the bogies really tall or really long, and I wasn't happy with it.

Spoiler

cam06040.jpg

nyc_baggage_140923a.png

 

 

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12 hours ago, Commander Wolf said:

How are you attaching these to the motor itself?

29173648821_4d335995c3_z.jpg

The top left are attached with 1x2 plates with clips on the short side (part 63868) and I build the sideframes out of SNOT plates with clips and bars. It also gives a slimmer profile to the sideframes, which I prefer. There's a bit more explanation on my Flickr.

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