Large Scale Central

Need suggestions for a motor block

Modeling Motive Power
#1

I have been dreaming of building a critter similar to Rockhill Trolley Museum’s M-25…

I would be using the hood and body from a Bachmann 45 Tonner and scratch build side frames and other small details. I’m not looking to model M-25, but rather build a large, but short wheelbase, narrow gauge switcher. I have no experience with the available motor blocks so I am open to suggestions. I’m not too concerned with wheelbase, but it would be best if it was fairly long.

Of course, this is yet another project that may never get built, but with stuff getting scarce I thought I better think about gathering needed parts now. I already have a donor body.

#2

Hartland’s Mack/Sparky motor block is sturdy, reliable, and available as a part.

With that and the Mack’s frame you’d have a good foundation

Here’s what it looks like

#3

Thanks Forrest, I will check that out. I suspect the Mack frame will be too small, but it might be of value for bashing the side frames.

Was thinking last night about where I could stuff all the electronics. I might try to sling 4 LiIon cells under the deck in front and behind the motor block if there is enough space. I will likely use a sheet of 1/4" acrylic as the frame/deck.

Suddenly this bash is sounding more fun that the Porter bash I have planned.

#4

Why not start with an Aristo Lil Critter? Readily available on used market, and you can buy replacement motor blocks now.

#5

Greg Elmassian said:

Why not start with an Aristo Lil Critter? Readily available on used market, and you can buy replacement motor blocks now.

They are one I’ve been curious about but have not yet seen in person.

Going to have to remember to look up what their motor block looks like.

EDIT: Oooooh, they have all manner of handy detail bits too. http://www.gbdb.info/data/zeichnung/Aristo-Craft/22501.pdf

Even basic cab interior details.

Uhh, 1/29 scale?
I’m building in 1/24.

#6

Right, wrong scale, but a good platform to build from, remember the SG RS-3 mods done by a few people to model a NG unit in a larger scale? The prototype Jon shows is pretty flat-sided, maybe just build “over” the existing shell.

Anyway, lots of little pieces to play with.

Greg

#7

Little Critter loco is the wrong scale (I’m doing 1:20.3 or Fn3) - a standard gauge critter gauged to 3ft ill be BIG. The Aristo motor block would be an option.

Edit to add that I found my original thread here on LSC dated October 2006. I don’t procrastinate much, do I?

#8

That was what I was saying, use the brick and the chassis for a foundation… I get it’s 1:29, think this is the second time I have atoned for that (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-sealed.gif)

#9

Greg Elmassian said:

That was what I was saying, use the brick and the chassis for a foundation… I get it’s 1:29, think this is the second time I have atoned for that (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-sealed.gif)

Third time is a charm, Greg. (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-foot-in-mouth.gif)

#10

Without doubt the Aristocraft motor block used in the Rs3, U25b and Budd railcar is without peer. I suspect the AR Li’l critter too.
It has ball bearing axles and a three point suspension.

#11

Jon Radder said:

Little Critter loco is the wrong scale (I’m doing 1:20.3 or Fn3) - a standard gauge critter gauged to 3ft ill be BIG. The Aristo motor block would be an option.

Edit to add that I found my original thread here on LSC dated October 2006. I don’t procrastinate much, do I?

Jon,

I believe I understand what you are trying to accomplish!

I have both the Hartland and Aristo motor blocks.

However in my mind without measuring both I PERSONALLY think the “Aristo” is the correct one you seek.

Do you know the wheel diameter on the 1:1 unit you would like to model?

I feel the Hartland Mack wheels scale out rather large and would be incorrect for the goals you would like to achieve.

On a side note I also believe Warren Mumpower committed himself to being a test bench for a plunger factory a few years back.

#12

Tony Walsham said:
Without doubt the Aristocraft motor block used in the Rs3, U25b and Budd railcar is without peer. I suspect the AR Li’l critter too. It has ball bearing axles and a three point suspension.

Agreed. I owned three of the second generation RS3’s at one time. They were excellent, smooth runners. So yes; I think Greg’s suggestion of thw Little Critter block is a good one.

#13

Tony Walsham said:
It has ball bearing axles and a three point suspension.

That makes a difference with these little 4 wheel critters when employing track power; the more time the wheel is contacting the rail, and the more wheels which are, the better.

#14

" Rooster " said:

Jon Radder said:

Little Critter loco is the wrong scale (I’m doing 1:20.3 or Fn3) - a standard gauge critter gauged to 3ft ill be BIG. The Aristo motor block would be an option.

Edit to add that I found my original thread here on LSC dated October 2006. I don’t procrastinate much, do I?

Jon,

I believe I understand what you are trying to accomplish!

I have both the Hartland and Aristo motor blocks.

However in my mind without measuring both I PERSONALLY think the “Aristo” is the correct one you seek.

Do you know the wheel diameter on the 1:1 unit you would like to model?

I feel the Hartland Mack wheels scale out rather large and would be incorrect for the goals you would like to achieve.

On a side note I also believe Warren Mumpower committed himself to being a test bench for a plunger factory a few years back.

The 1:1 M-25 was just inspiration. I don’t know the dimensions and don’t care. IF it gets built this will be a completely free-lance model. Some more inspiration can be found in the various GE units referred to by Matthew in that old thread. I particularly liked the look of this one…

  • I do remember Warren applying for that job. I do hope he keeps the equipment well lubricated.
#15

Jon Radder said:

IF it gets built this will be a completely free-lance model. Some more inspiration can be found in the various GE units referred to by Matthew in that old thread.

Lots of inspiration photos here, too, http://www.northeast.railfan.net/industrial.html

Fully accessorized pair of Plymouths, http://digital.denverlibrary.org/cdm/ref/collection/p15330coll22/id/52513 and http://www.northeast.railfan.net/images/hetc1171.jpg

If stripes are your thing, http://www.northeast.railfan.net/images/lerc2.jpg

If not stripes then how about checkerboard, http://www.northeast.railfan.net/images/jabc1.jpg

Low and close clearance cab, http://www.northeast.railfan.net/images/bmix0b.jpg

And for really low clearance, http://www.northeast.railfan.net/images/bscxl22.jpg

#16

Jon,

When I built my brass critter, I used an Aristo-Craft 29350 motor block. For some reason I thought of it as coming from an RS-3, but the invoice claims it is a GP-40 motor block.

Since you’re only going for inspiration, I suspect either might work, but they might be hard to find these days.

#17

Hmm. It seems like the motor block for the RS-3 is 29351. Price looks good and at least they seem available from a reliable supplier.

#18

If you get an older one, there might be a bit of maintenance: http://www.girr.org/girr/tips/tips1/brick_fix.html

#19

I do have a “spotters guide” for the various versions.

https://elmassian.com/index.php?option=com_content&view=article&id=354&Itemid=398

I really have not seen huge differences in the versions in terms of performance, except I would go with a ball bearing version.

Since this is a critter, it’s not going to be pulling heavy trains I would suspect. The older versions with adjustable lash, once adjusted seemed fine to me too.

The biggest thing in buying a used one is to be sure you don’t have the “cracked axle” situation, very much the same as USAT has, not a prevalent, but can happen.

Greg

#20

Oh, Oh, I forgot, ya gotta do this exhaust!
http://www.northeast.railfan.net/images/qbcrl2517.jpg

Is that not cool. (https://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)