3/4" scale, 3-1/2" gauge K4 class 4-6-2 "Pacific"; Pennsylvania Railroad
A 1929 advertisement for the 3/4" K4 in "The Modelmaker" magazine. You can buy the EXACT castings that were mentioned in this ad, and build your own K4, today.....NINETY years after the ad was run.
The elevation drawing of the 3/4" scale, 3-1/2" gauge K4 "Pacific" by H.J. Coventry.
Designed by H.J. Coventry beginning about 1919 and available commercially from the late 1920s until about 1960; design was updated with minor changes circa 1959-1960.
Walschaert Valve Gear
Steam Clearances, and Exhaust Ports, "cored" into the cylinder castings. No complex "step boring" or difficult drilling required.
Hand Pump in the tender; left and right injectors on the engine
5" diameter Copper boiler; silver soldered. Seamless 5" tube may be purchased from suppliers in the UK, or it can be "rolled" from flat copper sheet and the joint silver soldered.
Belpaire Firebox, with cast bronze throat sheet for easier fabrication
Machinery Requirements: 9" or larger lathe (10" lathe recommended), small to medium sized milling machine, drill press, grinder, hand tools.
The complete set of drawings is available below, for live steamers who may want to look the project over before buying castings. (If you are outside the USA and would like these drawings shipped to you, please inquire).
A complete castings list may also be seen below.
Thank you for your interest!
Section 1: Frame
Mr. Coventry's K4 uses a steel frame, comprised of left and right frame sections which are 3/8ths inch thick each (which you may purchase locally or online); the frame has various bronze castings attached for functionality, appearance, and overall rigidity of the frame assembly. These frame castings are exactly the same as were offered by H.J. Coventry for his "K4" beginning back in the 1920s. You cannot tell the difference between these, and those cast almost a century ago. They are sand cast at a local foundry in New England, USA.
The Frame Section for the 3/4" scale K4 "Pacific" by H.J. Coventry is now available. Bronze "sand castings" are made in New England, USA to Mr. Coventry's original (1920's) specifications. Note: trailer truck sideframes are included in this photo for clarity and "good looks", but are not included in the "frame section". They may be purchased with the "trucks" section, available below.
Section 1: FRAME
Frame Brace (2)
Draft Casting (drag beam)
Trailer Truck Pivot Bracket
Front Corner Bracket (2)
Trailer Truck Bearer Bracket (2)
The Paypal button on the right is for your K4 "Frame Section" to be shipped to the USA. Note: left and right "trailer truck sideframe" castings (shown in photo for clarity and appearance) NOT included. They may be purchased with the "Trucks" section, below. (For shipping to other countries, please inquire.)
The Paypal button at left is for your K4 "Frame Section" to be shipped to Canada. Note: left and right "trailer truck sideframe" castings (shown in photo for clarity and appearance) NOT included. They may be purchased with the "Trucks" section, below. (For shipping to other countries, please inquire.)
The 3/4" scale H.J.Coventry K4 cylinder section. Produced 2018 for the first time in almost 60 years. The castings have ribs on their outer faces to facilitate machining setups, and the steam chests and exhaust ports, are "cored" internally. This coring eliminates a drilling and boring operation that would have been a difficult job for the amateur machinist to accomplish. Sand cast in New England, USA.
The Paypal button on the right is for your K4 "Cylinder Section" to be shipped to the USA. (For shipping to other countries, please inquire.)
The Paypal button at left is for your K4 "Cylinder Section" to be shipped to Canada. (For shipping to other countries, please inquire.)
Section 4: TRUCKS
Engine Truck Bolster
Engine Truck Transom
Engine Truck Center Plate
Engine Truck Wheels (4)
Trailer Truck Bearings (2)
Trailer Truck Wheels (2)
The "Trucks" Section for the 3/4" scale K4 "Pacific" by H.J. Coventry is now available. All components "sand cast" the old-fashioned way in New England, USA to Mr. Coventry's original specifications of 1919 (updated 1960). Firearms cartridges are shown for size reference only and are not included. At left is .22 caliber "long rifle", and at right is ".38 Special".
Click the Paypal button at right for your K4 "Trucks" section to be shipped to the USA.
Click the Paypal button at left for your K4 "Trucks" section to be shipped to Canada.
Section 5: BOILER & Accessories
Front Tube Plate
Steam Dome Cap
Steam Dome Cover
Sand Box (sand dome)
Safety Valve Flange
Cab Reverse Gear Bracket Smokebox Front
Engineer Brake Valve
IN PRODUCTION 2018
Section 6: TENDER
Tender Draft Casting (2)
Rear Footsteps at Tender
Front Footsteps at Tender
Body Bolster at Tender (2)
Tender Truck Frames
Tender Truck Bolsters
Tender Truck Transom
Tender Truck Bearings (8)
Tender Truck Wheels (8)
Tender Tank Filler
The "Tender Section" for the 3/4" scale K4 "Pacific". These parts have not been cast in FIFTY or more years, and are EXACTLY the same as the castings formerly available from Mr. Coventry during the era from about 1920 to about 1960. All are traditional "sand castings" made in New England, USA.
The Paypal button on the right is for your K4 "Tender Section" to be shipped to the USA.
The Paypal button on the left, is for your K4 "Tender Section" to be shipped to Canada.
The H.J. Coventry K4 Pacific in 3/4" scale, 3-1/2" gauge. (Photo by Errol Groff, used with permission).
The 3/4" Scale, 3-1/2" gauge Pennsylvania Railroad K4 class 4-6-2 "Pacific".....the standard locomotive from the "Standard Railroad of the World". Designed by H.J. Coventry in the 1920s. Photo by Bernie Grow.
An example of the H.J. Coventry 3/4" scale, 3-1/2" gauge K4 "Pacific" under steam at Waushakum Live Steamers in Massachusetts, October 2008. This is a slightly modified version of the Coventry original, but the general outline is the same.
The tender, the backhead, the firedoor, and of course....the FIRE! This 3-1/2" gauge 4-6-2 will pull a few adults or several kids.....and will provide all the thrills of small-scale live steam operation that the hobby's pioneers, and those who came later, experienced and enjoyed for decades.