Bachmann Pennsy K4 Driver sizes on model

[kiwi_al]

Has anyone got the Bachmann N Scale K4?
If you have would you mind measuring the Driver tire size please?
Many Thanks.

[Lemosteam]

@kiwi_al The non traction tire diameter is 11.95mm [0.470"] at tire, 12.88mm [0.507") at flange OD.

[71jeep]

Wow they are .030 smaller than they should be I guess this is why they never looked right to me so I have not bought one.

[SkipGear]

Wow they are .030 smaller than they should be I guess this is why they never looked right to me so I have not bought one.

Just like every other N scale steam loco. About as close as you can get is to match the flange diameter to the actual wheel diameter unless you want a loco that will only run on perfect track with a minimum radius of 10'. Scale flanges are impossible. A running loco requires compromise. If I remember correctly the wheel base is pretty much spot on. The drivers are as big as they can be and still keep the wheel base accurate.

[mmagliaro]

It's a compromise to allow for N Scale flanges, inter-driver clearance spacing, and how much you want to stretch the overall wheelbase.  The brake shoes, driver rims, and driver spacing are kind-a chunky on that model.  Personally, I'd opt for making the drivers full-size and let the overall wheelbase stretch to allow for the necessarily oversized N Scale flanges and the inter-driver spacing. I think those things show a lot less than undersized drivers.

[kiwi_al]

@kiwi_al The non traction tire diameter is 11.95mm [0.470"] at tire, 12.88mm [0.507") at flange OD.

Thanks John,
I've recorded that in my kitbash book for future reference, I'm not bothered whether the size is correct for Pennsy just the size so I can kitbash Santa Fe steamers.