7mm US model dabblings

[richard carr]

The main reason I have had the chance to post so much this weekend is because I'm here in Chicago again, with a fair bit of spare time as it gets dark at 4:30 in the afternoon. I haven't really finished posting the October trip yet, but this morning I came across something I wasn't expecting at all. I started out at Bensonville Metra station which is the western entry point to Canadian Pacific's main yard in Chicago. It is just to the south of O'Hare airport so if you want to go train spotting and plane spotting all at once you can !


To be honest on the train front nothing was happening, there was a bit of switching going on in the yard but it was too far away to see anything worthwhile. So I took a drive along Franklin Street that parralells the southern edge of the yard. There is a lot of raod construction going on and it got the point where the road was closed and a diversion was in place, but as I approached the diversion, I saw this



It must be quite a while since this had a new paint job, I'm not certain what it is ? is it a GP15 of one kind or another ?

Here are a few more photos








Thinnking about it, if it has a fan at the back it can't be a GP15, so Jordan can you enlighten us please.

 

[mickoo]

GP38-2 with winterization hatch.

GP15 have a big radiator opening at the base of the hood at the rear like SP/DRG/UP tunnel motors, no filters high up like the rest of the GP's and the fans are buried inside the body work. They're often nicknamed 'baby' tunnel motors.

Bagged this one at Yermo CA

 

[Jordan]

GP38-2 with winterization hatch.

Beat me to it! although there look to be other "post-SOO" modifications too, not least of which is the fitting of remote controls.

 

[JasonD]

Richard, the other end of the yard at Mannheim station on Front St is easy to park, commuter and CP action. Mind you, March 2019 was my last visit
Jason

 

[Jordan]

Whilst mucking about with Atlas freight trucks this weekend, and lamenting the narrow axles, I've had an idea that is either just stupid, or rather good,I'm not sure which...
Would it be possible to draw and 3D print a prototypical thicker cosmetic axle 'overlay' sort of thing, in two halves, which could then be superglued together over the existing axle & painted, to make it look better?
Lunacy or Genius...??

 

[richard carr]

Possibly genius, I'm fairly sure that would work, and you can have a tapered axle.

Jason

I would have gone to Mannhiem but the road was blocked and there was a lengthy diversion to get there and I still wanted to go to Des Plaines Hobbies.

 

[Rob R]

Stick a dimensioned doodle up on here and I'm sure someone will have a 3D play.

 

[mickoo]

Not mad at all and something I wanted to try when I find time. Rather than split the print I was going to make it one piece with a corresponding hole in the middle. Pull off the insulated wheel, slide on cosmetic axle, refit wheel.....simples.

 

[Rob R]

There is probably room for both designs.
If you have the truck in bits anyway then the one piece makes sense, for a quick and easy then the split design would be the way to go.
Still need that dimensioned doodle..................

 

[Jordan]

Not mad at all and something I wanted to try when I find time. Rather than split the print I was going to make it one piece with a corresponding hole in the middle. Pull off the insulated wheel, slide on cosmetic axle, refit wheel.....simples.

Only 'simples' sort of...
I prefer two split halves as the whole truck doesn't have to be dismantled to get the axles out,then wheels pulled off. Most MTH cars I have need dismantling themselves to get the trucks off too!!
Far easier to just glue two halves over each axle in situ.

 

[Jordan]

Still need that dimensioned doodle.......

I don't have a vernier caliper so any measurements I take would be a bit 'best guess'- especially the crucial axle diameter of the Atlas wheelset.

 

[Overseer]

Still need that dimensioned doodle..................

No doodle but the Atlas axles are 2.5mm, or a fraction under, diameter. I measured both a tapered end axle and a 'roller bearing' axle. Length is 26.9 or 27 between the insulting bushes (which are around 5mm diameter). There is knurling on the axle which sticks out a bit past the insulating bushes so it would be worth increasing the internal diameter for 0.5mm at each end.

 

[daifly]

insulting bushes

Damn it, you’ve corrected the spelling!
I had this ready to post so here it is anyway.

 

[Rob R]

No doodle but the Atlas axles are 2.5mm, or a fraction under, diameter. I measured both a tapered end axle and a 'roller bearing' axle. Length is 26.9 or 27 between the insulting bushes (which are around 5mm diameter). There is knurling on the axle which sticks out a bit past the insulating bushes so it would be worth increasing the internal diameter for 0.5mm at each end.

Thanks Fraser, that takes care of the internals, all that is needed now is the protoype axle external diameters and I will fire up the TinkerCad...........

 

[mickoo]

Not as easy as that, there are dozens of types of axle.

Barber 75T axle



Axle specifications for roller bearing wheels, it may cover 100T Barbers, I'll let you decipher and pick the bones from it.

 

[Jordan]

Not as easy as that, there are dozens of types of axle.

All I want is something fairly common/typical/generic, possibly tapered as suggested earlier, and thicker than the spindly Atlas axle! I'm not taking up axle spotting as a hobby!!

 

[Big Train James]

Just use the specs for the Class F bearings. That's the type found on most modern rolling stock of the 70/100 ton variety. And only bother with the L, K, E, J, and DJ dims.

 

[Rob R]

I reckon summat like this:-

The taper is very subtle but it is there honestly..

 

[Rob R]

.stl files if anyone wants to have a play before I re-commission my printer

 

[richard carr]

Rob

It just needs a little bit more of a taper, sometimes we need to exaggerate things to make it look right in model form.


Richard