Blackstone Authentic HOn3 model locomotives
Blackstone Models is dedicated to the creation of high quality models, craftsmanship with state-of-the-art technology. SoundTraxx sound decoders and speakers, with expertise in model train electronics, with dedication to quality and performance, has evolved into authentic HOn3 model locomotives.
Blackstone Denver & Rio Grande K-27 narrow gauge locomotive
A Little Background In 1903, the Denver & Rio Grande took delivery of fifteen class 125 2-8-2 narrow gauge locomotives built by the Baldwin Locomotive Works. Eventually re-classified as K-27s and nicknamed Mudhens by their operating crews, the new locomotives boasted a tractive effort of over 27,000 lbs. and ushered in a new era of narrow gauge pulling power for the ever expanding railroad. All fifteen K-27s (numbers 450 to 464) were originally equipped with Vauclain compound cylinders but due to high maintenance costs, were soon rebuilt with single expansion cylinders and slide valves. Later, eleven of these engines were upgraded again, this time with modern piston valve cylinders. Today, there are still two surviving and operating K-27s. Blackstone Models is pleased to introduce the K-27 in the modern piston valve configuration. Faithfully reproduced in HOn3 scale, the Blackstone K-27 features die cast construction accented with numerous detail parts. The K-27 is optionally available with state-of-the-art electronics including a SoundTraxx Tsunami Digital Sound Decoder. The Tsunami-equipped Blackstone K-27 sounds as good as it looks and will operate on both DC and DCC controlled layouts. All at a price thats less than a third of todays brass imports!
K-27 Mudhens History
K-27 Mikado History
by Jeff Johnson
‘Those things are little monsters’. While this reference to a mere 63-ton locomotive in the steam heyday of the early 1900’s may have seemed to be a bit of an exaggeration, enginemen of the Denver and Rio Grande Railroad had cause for excitement on the narrow gauge.
In April and May of 1903, Baldwin Locomotive Works delivered fifteen 2-8-2 Vauclain Compound locomotives to Salida, Colorado. Numbered 450 to 464 and resplendent in their freshly applied livery, thus began the ultimately checkered career of the Mudhen. Originally designated as class 125 (the “K-27” designation was adopted in 1924), they were the largest narrow gauge power the D&RG had purchased to date.
So what was the buzz all about? Up to this point the D&RG narrow gauge had utilized the ever-present 2-8-0’s and 4-6-0’s from the 1880’s to carry the burden of motive power for the line. The narrow gauge men had not experienced locomotives of this relatively grand size and wheel arrangement, much less the newer Vauclain Compound style of using steam. Although a higher rate of pay was awarded to enginemen operating the compounds, it can be easily presumed that crews found it disconcerting that the bigger power would also reduce the amount of engines (and thus labor) needed to handle the expanding business on the railroad.
Vauclain Compound Style, H.L.Curtis Photo, Gunnison 1905. Photo Courtesy John Maxwell Collection.
Necessity is the mother of invention (and hard work), so right of way improvements and a little mechanical “getting used to” were among the adjustments the railroad men had to make while breaking in the new machines. Track upgrades were dictated by the fact that the new engines required a minimum 52lb. rail weight for safe operation.The outside frame arrangement of the running gear meant that the counter-weights (or “cranks”) were well outside of the total width of the rails. The low-slung appearance of these cranks turning just above the ties gave the engines the appearance of almost “waddling” down the sometimes tenuous narrow gauge track. From this observation, the ultimately well-known moniker of “Mudhen” was adopted by operating crews when referring to this class of motive power.
Changes For The Mudhens
The original Vauclain Compound design was conceived in the interest of increasing the efficiency of steam’s expansive force. The more common locomotive design (simple) exhausted the steam after it expanded once in the driving cylinder. The Vauclain Compound system first admitted steam to a smaller high pressure cylinder, then used the steam again in a larger low pressure cylinder prior to being exhausted to the atmosphere.
Slide Valve Era, Otto Perry Photo, June 6, 1923,
No. 463 at Chama, New Mexico.
Photo Courtesy Denver Public Library
Only a few years after the locomotives’ arrival, some impractical design issues with the Vauclain Compound begged for new solutions. The unexpected result of much higher maintenance with this cylinder and driving arrangement forced the railroad to consider another option. Thus, beginning in 1906, the class 125 locomotives were eventually changed to a simple, single expansion design with “D” style slide valves. This change was in keeping with the design of the other narrow gauge power and served the engines well for over a decade.
In 1917, the Denver & Rio Grande engaged an independent auditor to evaluate the railroad and recommend improvements to keep the line competitive. Among other suggestions, the advice to convert these fifteen 2-8-2’s to piston valves and Walshaert valve gear was partially heeded. By 1929, all but four of the Mudhens sported the piston valve arrangement. Other gradual modifications brought about new, larger tenders and super heater installation. Locomotive number 462 was the only piston valve conversion that did not receive super heating. The 450, 451, 457, and 460 remained with the simple slide valve arrangement (and lack of superheating) to the end of their relatively short careers.
Piston Valve Era, Otto Perry Photo,
September 5, 1936, No. 463 at Montrose, Colorado
Photo Courtesy Denver Public Library
While eventually being used faithfully across the entire narrow gauge system, newer, more powerful locomotives delivered in the 1920’s had relegated the now comparatively small K-27 to less prestigious service. The toll of the great depression on the Colorado narrow gauge sent many of the locomotives into storage at Alamosa. The 450, 451, and 457 never returned to the rails beyond the early thirties. By the mid 1940’s, four K-27’s had been scrapped, two were sold to another railroad, and two others were primarily in yard switcher service. However, a struggling little cousin railroad helped keep the Mudhens waddling along.