ACL Class R-1 4-8-4's the "Eighteen-hundreds"

Specifications

General data on the R-1 from the ACL

The R-1's were overhauled at the ACL shops in Tampa, Florida, as they were too large for the road's backshops in Rocky Mount, North Carolina. Tampa is southwest of the ACL's Jacksonville to Richmond mainline, which required the locomotives to stray from their usual operating territory when heavy repairs were required. When a locomotive was sent to Tampa for overhaul, it was used on a freight train into Tampa. The R-1's were limited to 40 MPH over most of this line south of Jacksonville, and even slower over some bridges, so this must have been a headache for the railway.

An interesting feature on the R-1's which I have not seen on other modern steam locomotives was the omission of wedges from the frame pedestal openings. Wedges allowed the gaps between the pedestal openings and the axle boxes (which contained the roller bearings) to be adjusted for proper clearance. Earlier versions of wedges had to be manually adjusted by machinists when the engines were brought in for maintenance. Turning a bolt located below the wedge, raised or lowered the wedge, reducing or increasing the clearance between the frame opening and the axle box. Around 1940, Franklin introduced self-adjusting wedges, which included an adjustable spring to shift the wedges to maintain proper axlebox clearance over long periods without intervention by shop personnel. The pedestal openings on the R-1's had to be adjusted by inserting shims of the appropriate thickness between the shoes and the frame. At overhaul the axle openings in the frame would have to be trued by grinding or welding up and then grinding. Perhaps Baldwin or the ACL believed wedges would no longer be needed with cast bed frames and that adjustments would rarely be required, but this was apparently not the case.

Interestingly, according to former ACL machinist Jerald McGowan, the main driving axles required replacement at every overhaul as machinists invariably found a tiny crack in the axle at the inner edge of the wheel hubs. It was such a common problem that partially finished replacement main axles were maintained in stock at Tampa so they'd be available when the engines were overhauled.
 Interestingly, the drivers were not keyed to the axles but relied on the press fit to keep them quartered.

Few changes were made to the R-1's during their careers. Provisions were made in the original design to allow trailing truck boosters to be fitted, but this was never done. Photographs show that within the first couple of years of service, the original whistles, mounted at the steam dome and fed with saturated steam, were replaced with larger whistles mounted on the fireman's side of the boiler just behind the stack on the superheater header, where they were fed with superheated steam (see photo below). Headlights seem to have been changed or modified on some if not all of the locomotives as well.  In the 1940's, some or all of the locomotives were equipped with Valve Pilot devices, which gave guidance to the engineer operating a locomotive on the optimum valve cutoff setting ensuring maximum operating efficiency and fuel economy. Finally, locomotives 1800, 1801, 1806, 1807, 1808, and 1809 were fitted with Timken light-weight pistons, piston rods, crossheads, and new tapered main rods with roller bearing wrist pins (see photos  below). These components greatly reduced the mass of the reciprocating parts which improved the R-1's running gear balance even further. At least some locomotives had some drivers replaced with later versions of the Baldwin disk drivers.  A comparison photo of these is provided as well.

ACL R-1 Details of Interest

Builder's Photo (above) of R-1 showing (1) original headlight, (2) original whistle fed with saturated steam from the steam dome, (3) heavy, one-piece forged crosshead and (4) heavy, non-tapered main rods. This photo also shows the ASF wheelsets on the lead truck, indicated by the large hubs with bolts around the perimeter, which were an interesting development of the 1930's.  These wheelsets included both roller bearings and conventional journal bearings on each axle. Apparently the purpose of this arrangement was to allay the fears of conservative railway managers, some of who did not trust the relatively new roller bearings.  The friction bearings on the ASF wheelsets could serve as a back-up if the roller bearings should fail. Other notable locomotives equipped with these axles were the massive 2-8-8-4's of the Duluth, Missabe, and Iron Range Railway in Minnesota. These axles, which were undoubtedly considerably more expensive than a conventional axle, were used for a relatively short time on new locomotives, as railroads' experience proved the reliability of roller bearings.

Late photo (above) of ACL R-1 showing (1) what appears to be a different headlight, (2) larger whistle fed with superheated steam from the superheater header, (3) Timken light-weight crosshead (not seen are Timken light-weight piston and piston rod), and (4) light-weight, tapered main rod with roller bearing wrist pin. This photo unfortunately also shows the dirty condition somewhat typical of most ACL steam, especially near the end of steam on the railway.

It appears the original whistles were the standard Baldwin Locomotive Works whistle, which was usually a 3-chime whistle. The later whistles which were installed shortly after the locomotives were placed in service were likely the Atlantic Coast Line's own 6-chime whistles. You can hear one of these whistles on this short clip from the 1952 movie "the Greatest Show on Earth", where a much smaller ACL P-3 Pacific pulls a circus train: Atlantic Coast Line P-3 Whistle

This photo shows a brand-new set of Baldwin disk drivers awaiting installation on a new steam locomotive, possibly an ACL R-1. These wheels were of hollow cross-section, similar to the better known Boxpok drivers used on many modern steam locomotives. Many contemporary Santa Fe locomotives were also equipped with Baldwin disk drivers, and many other locomotives on a variety of railways were retrofit with these wheels during updates in the 1930's and 1940's. The ACL installed Baldwin disk main drivers on many of their steam locomotives in the 1930's and 1940's including the P-5 Pacifics and Q-1 2-10-2's. The hollow cross-section made the wheels stronger and allowed more room for counterbalancing material.

 

Baldwin later somewhat simplified the design of these wheels by omitting the raised ribs between the openings and photos show that at least some R-1's wound up with the newer version of the wheels. The two photos above show the main drivers on R-1 no. 1808; the left photo shows the original style and the right photo shows the newer version of the wheels.  The other drivers were not changed on this locomotive. Sante Fe 4-6-4 no. 3463, currently on display in Topeka, Kansas also sports two different versions of Baldwin disk drivers, indicating some drivers were replaced over the locomotive's life, so this may have been a common issue. The reason for the change is not known, but perhaps there were issues with at least some of the wheels cracking after many miles of use.

Another interesting feature of the R-1's were the Atlantic Coast Line heralds on the tender, which were embossed 45 inch diameter plates bolted to the sides of the tender rather than just a logo painted directly on the tender sides. The plates were provided by the Allen-Morrison Sign Company of Lynchburg, Virginia. Allen-Morrison was famous for making many of the now-collectible Coca-Cola signs, as well as other signs used in advertising. The builder's drawings for the locomotives show that rivets were omitted in the area of the tender where the heralds were installed. Welding was used to secure the internal braces to the exterior sheets in this area. The rivet-free area can be seen on the photo of N&W 2084 with the herald removed on the Disposition page.

The R-1's were well-designed steam locomotives and were nearly state-of-the-art for 1938, lacking only roller bearing axles on the trailing truck and tender axles. Their large fireboxes with combustion chambers and 4 Nicholson Thermic Syphons were among the largest in heating surface area of any 4-8-4 and undoubtedly made them prodigious steamers. One curious feature is Baldwin's use of relatively small piston valves for such large engines which seems to have been part of Baldwin's design philosophy at the time. The R-1's had only 12 inch diameter piston valves whereas even the ACL's much smaller and older Class P-5 Pacifics had 14 inch valves. The R-1's also had somewhat smallish superheaters for their size (Type A, 1425 square feet). These two items would have restricted their "breathing" at high speed by impeding the steam flow into and out of the cylinders, resulting in a pressure drop from the boiler to the cylinders. Later 4-8-4 designs used 14 inch piston valves with even longer valve travel and huge Type E superheaters to improve their high-speed performance. Nonetheless, once their balancing problems were corrected, the R-1's were known as outstanding performers on the ACL and their theoretical design deficiencies were not seen as drawbacks when they were in service.