I know this isn't the answer you want to hear, but ever considered
using that model as a background model on your layout? Just have it
parked on a siding or in a loco terminal or something. Could you
possibly get a new SD35 in whatever road name you could find
inexpensive and swap the shells?
>> Could you possibly get a new SD35 in whatever road name you could
I thought you said they'd redesigned the drive, correcting the
problem, but that finding the replacement parts for older units was
hard. If that's the case, then buy a newer unit and replace the
But why would I buy another engine from a company that admittedly marketed a
defective product and then refused to stand behind it when things went
If they'd do it once without apology, they'd certainly do it again!
Every era seems to have its life-limiting issues. Almost no Dorfan survives
due to disintegration of the die cast alloy they used. Some batches of
prewar Lionel had similar problems (warped bellies is a common problem on
the O-72 City of Salina sets), as did a lot of postwar John English, and to
a lesser extent Ulrich and early Mantua and Roundhouse.
I find the problem of the plastic era is splitting of drive components made
from the tough Nylon - Delrin - etc. type engineered plastics. A high
percent of the RoCo made Atlas O scale F-9s I have encountered have cracks
in the axle gears. It is as if the parts were designed with too tight an
interference fit between the gear and the half axles, and/or these plastics
become more brittle with age. The crack starts at the axle, but radiates
out through the gear, resulting in one pair of gear teeth with an extra
large spacing that results in a "clunk - clunk - clunk" as it runs (if it
runs). Fortunately, these F-9s have hubs on the gears, and I have been able
to repair them by putting collars made from K&S nesting brass tube around
the hobs, then reaming out the axle holes for a less tight fit, and
reassembling. I have had the same problem with a variety of Bachmann
items - a G-gauge trolley and several of the Chinese made split chassis HO
locomotives. Unfortunately these don't lend themselves to repair. I have
not found Athearn to have this problem, but they seem to have used a less
exotic plastic for their drive components.
I wonder if the problem 30 years from now with the current generation of
models will be electronic? (How many people can still read and have
software that can interpret the data on their old 5.25" floppies, or play
8-track tapes?) If one wants models that will have prolonged service life,
I think brass is the sure bet. The worst I've found is disintegrated foam
packing that has ruined a couple paint jobs, and dried out rubber tube
couplings between the motor and worm. Geezer
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