Berkshire HO driver diameter

[Pennywhistle]

Berkshire HO driver diameter
Can somebody tell me the dimension in actual inches of the Bachmann HO Berkshire's  drivers? I'm not talking about the prototype dimensions but the actual dimensions of the drivers on the model.
For kit-bashing purposes, I want to use the Berkshire as a starting point. However, the drivers need to be .930 inches in diameter (or close to that). If not the Berkshire, then perhaps another larger locomotive would work.

Justin

[jonathan]

Just googled the Berk.  Depending on which road it was built for, the Berk had drivers from 69" up to 72.83".  Scaled down that's .7931" to .8371".-- a bit smaller that you are looking for. Your prototype has 81" drivers?  That's pretty large--I think some Pacifics had drivers that big.

Regards,

Jonathan

Addendum.  I realize you are asking about the model.  I had a Berk--great loco.  I never measured, but I'm pretty sure the drivers weren't that big.

[ebtnut]

The PRR K-4 Pacific has 80" drivers, which should be "close enough" to what you need. 

[Pennywhistle]

Thanks to all of you. I'll take a look at the PRR Pacific. I'm looking at the mechanism to build an ON30 Erie L1. That has to be the ugliest locomotive on earth. It was a 0-8-8-0 articulated Camelback...The only articulated Camelbacks ever built. There were three of them, numbered 2600, 2601 and 2602.

Justin

[J3a-614]

The NKP Berkshire had 69 inch drivers; an HO model's drivers would scale out to 38 inches in O scale. The 80 inch drivers used under an HO K4 (or Bachmann's large drivered 4-8-4s, such as the Daylight) scale to 44 inches in O.  

Actual diameters, if to scale (ours are usually a tad smaller to account for oversized flanges) are 0.79 inches for the 69s and 0.92 inches for the 80s.

For comparison, I believe the HO 2-8-0 has 63 inch drivers.  Those would scale to 34 inches in O, with an actual diameter of 0.72 inches.

Just for additional comparison, the Erie L-1 had 51 inch drivers (actual size 0.59 inches in HO, scaling to 28 inches in O). That's a size normally associated with switchers, such as the Bachmann USRA 0-6-0!  That says much about the service and operating speeds of the prototype.

For a freelanced model such as this one would be, proportions that "look right" would be a better consideration than an actual driver diameter scaling out.  In other words, for this project you might want a slightly larger diameter than a scale translation from 51 inches.

Hope this helps out.  

https://www.steamlocomotive.com/locobase.php?country=USA&wheel=Articulated&railroad=err#5700

[charon]

Justin;
Can you post a picture of that 0-8-8-0 camelback?  It sounds interesting.
Thanks;
Chuck

[J3a-614]

Justin;
Can you post a picture of that 0-8-8-0 camelback?  It sounds interesting.
Thanks;
Chuck

It so happens a couple of pix show up with the link above on the Erie engines.

http://www.northeast.railfan.net/images/erie2600.jpg

http://www.northeast.railfan.net/images/erie2601.jpg

[Trainman203]

Scroll down to the D&H experimental engines.  They are way, way ahead of this articulated camelback in the ugly engine contest.

http://www.douglas-self.com/MUSEUM/LOCOLOCO/USAhp/USAhp.htm