Boxpok Drivers

[Sokramiketes]

I'm drawing a blank... are there any Bachmann steam engines with more modern Boxpok drivers that could be swapped into a heavy mountain?

Or has everything been spoked?

[nickelplate759]

The Bachmann Santa Fe 4-8-4 has Boxpox drivers, but I'm not confident that they would be good to use on another model.

[garethashenden]

The 4-6-4 Hudson has Boxpox wheels. No idea about swapping them though.

[Sokramiketes]

Thanks guys.  I guess I'm looking for something in the 69" diameter range.  The EM-1 may have compatible design but 64" or so (guessing from prototype).

Maybe a project in printing new plastic centers. 

[btrain]

I don’t know how good BLI’s parts department is, but Reading T-1s have a 70” box pox drivers.

[kiwi_al]

You have 3 choices (there will be more - Murphys Law) Bachmann 4-6-4 Driver size on the model - 72", Bachmann 4-8-4 northern 73", BLI T1 ~67" (66.7717")

[Missaberoad]

Illinois Central?

[Sokramiketes]

Illinois Central?

Yes!  Well, the HO model I'm trying to match in N started out as an IC mountain. 

[randgust]

This is another situation of appearance vs. performance.

Swapping drivers is a real PITA, mostly trying to get quartering accurate, either that or on all-gear drives, setting the wheels in the same quadrant compensating for the gear train slop.   i've fought that battle several times, lost twice, got so bad on the Decapod I finally pulled the crankpins on one driver set because I just couldn't beat it, still had a low speed visible 'hop'.

Then you get into axle diameters, crankpins, wheel profile, flanges.....

One of the more brilliant things I ever saw done was photoetched overlays on the Kato critters for spoked wheels with counterweights for a Heisler.  Still have a set.  But that's an offbeat solution.   I'd think you need to focus on getting a smooth and perfect chassis, and do the best cosmetic job you can. 

And also look at some of the Japanese models, a lot of those had boxpox drivers and Kato, Tomytec, and Microace have done some nice steam that has excellent performance.
See https://www.newhallstation.com/images-lib/microace_n_scale/MA-A9504/MA-A9504_01_lg.jpg   

[thomasjmdavis]

I'm hoping there is an answer to be found that does not involve machining, as I have a project (well...some of the parts for a project circa 2026 or 27 or whenever the other 150 projects are done) along similar lines. 

Just curious, Mike.... are you modeling a prototype with boxpok drivers on all 4 axles, or one with boxpok on only one axle (like the ATSF Mountains later in life) or 2 (like the GTW Mountains)?  Hoping you are successful, as I am contemplating using the same mechanism for either the ATSF or GTW....but I'll probably just accept the spoked drivers as is, not having the talent to make my own. 

My thinking is that a simpler option for me would be to mix the chassis with 4 boxpok axles, and make a GTW Northern out of it.

[Sokramiketes]

I'm hoping there is an answer to be found that does not involve machining, as I have a project (well...some of the parts for a project circa 2026 or 27 or whenever the other 150 projects are done) along similar lines. 

Just curious, Mike.... are you modeling a prototype with boxpok drivers on all 4 axles, or one with boxpok on only one axle (like the ATSF Mountains later in life) or 2 (like the GTW Mountains)?  Hoping you are successful, as I am contemplating using the same mechanism for either the ATSF or GTW....but I'll probably just accept the spoked drivers as is, not having the talent to make my own. 

My thinking is that a simpler option for me would be to mix the chassis with 4 boxpok axles, and make a GTW Northern out of it.

I picked up an extra set of spoked drivers from Bachmann, so I'll see what the new insert plan looks like.  The center plastic certainly doesn't pop out easily.  Perhaps the play is to carve down the spoked insert, leaving the connecting pin holes (all nice and quartered) and inserting a cosmetic overlay.  Either thin and etched, or better, if depth is available, printed for the look of a cast wheel.