This web site features images scanned from two booklets distributed by The Pilliod Company of Swanton, Ohio, a sales booklet and a Spare Parts Catalog. The Pilliod Company is now Swanton Welding & Machining Company, metal fabricators and manufacturers of precision parts.

The Baker Locomotive Valve Gear was the invention of Abner D. Baker (born 1861), whose A. D. Baker Company manufactured steam-powered farm equipment. Until around 1900 the Stephenson valve gear was almost universally applied to North American locomotives, but because its linkage is axle-driven inside the locomotive frame it is difficult to maintain and railroads began to favor external gears. The Walschaerts gear, outside the frame, is simpler but it controls valve motion and locomotive direction by means of a pivot that slides through an oscillating link. This type of connection is subject to wear, which affects the precision of valve gear settings. The advantage of the Baker gear is that all members are connect at fixed pivot points, resulting in greater equalization of wear. To study the operation of various steam locomotive valve gears, download the late Charles Dockstader’s Valve Gear Simulations. (Alternate updated site at this link.)

The Baker firm eventually became The Pilliod Company, which issued this sales booklet around 1915 to promote the Baker valve gear that had been applied to the locomotives pictured during 1911 through 1914. The booklet is entitled, simply, Baker Locomotive Valve Gear. The text consists of a brief foreword on pages 5-6 and a Guarantee on page 39, as follows:

The following pages contain convincing proof of the superiority of the Baker Valve Gear. The illustrations speak louder than words in testifying to the phenomenal success of the Baker Gear on engines of the leading railroads of the country.

Our idea in presenting the story of Baker success in this way is to give the busy motive power officials at a glance the best of evidence that the Baker Valve Gear, now used on over 2,200 engines, is the gear that has come to stay.


The Baker Valve Gear Guarantee

We unreservedly guarantee the Baker Valve Gear to be free from defects of material and workmanship and we will replace without charge any parts that prove defective within two years from date of installation.


Motive power shown ranges from 0-6-0 switchers through 4-8-2 Mountains and a 2-6-6-2 Mallet compound, plus the famous Erie 2-8-8-8-2 triplex. Locomotives supplied by American Locomotive Company, Baldwin Locomotive Works and Lima Locomotive Works for 21 railroads are included, along with some power retrofitted with the Baker valve gear in railroad shops.

Click on the selection below to bring up a full size image, or page through the booklet. With a few exceptions, the only commentary included is that printed with each image in the booklet, giving the number of locomotives ordered from each builder and the years. Click the link here or at left to view the Spare Parts Catalog.