Atlantic Coast Line R-1 4-8-4's

nw-mailing-list at nw-mailing-list at
Sun Oct 23 20:12:50 EDT 2005

Hi All,

Just joined the list after running across the archives of this list and the
thread a couple of months ago on the ACL R-1 4-8-4's.

I won't by any means try to say that the R-1's were equal to the N&W's J's
in power, but I do want to correct a point that was made against them.

Much has been made of the 1800's poor counter-balancing, but it should be
noted this was in their as-built configuration. The locomotives were
balanced to the latest AAR guidance at the time they were built, but this
guidance was found to be woefully incorrect for modern steam power. Baldwin
and the ACL spent a considerable amount of time diagnosing the problem and
as a result removed a significant amount of counter-balance material from
the drivers of the 1800's which corrected this fault. Arthur Bixby briefly
mentioned his experiences with the road-testing of the 1800's in his
"Trains" article on the New Haven 4-6-4's.

After these modifications, the 1800's were officially rated for 90 MPH in
passenger service on the ACL's Richmond to Jacksonville mainline. Later,
some of the 1800's were fitted with Timken light weight pistons, piston
rods, crossheads, and main rods (which evidently had friction bearing big
ends and roller bearing wrist pins). This was priobably an effort to
improve the balance of the R-1's even further.

It seems pretty certain that the N&W's design team paid close attention to
the counter-balancing problems with the ACL 1800's, and made certain to
learn from the ACL's lesson. I think it's fair to say that the success of
the N&W J's is at least in part owed to the ACL R-1's.

For any of you interested in the ACL R-1's, I have a webpage on them at:

Good Steaming,
Hugh Odom
The Ultimate Steam Page

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