Saturday, January 7, 2017

3d Printing a Bean Spray Track-Pull Tractor

See the previous article for a history of the Bean Spray Track-Pull Tractor.

Normally, I’m not much of a fan of making models “because they’re cool”; I’d prefer to focus on models that I can use on my model railroad, rather than build some cute models that will just get in the way. I'll usually describe projects that aren't appropriate for the layout as "spec(ulative) projects" in a pejorative sense. I don't have much storage space for random models, and would prefer to focus on stuff that will improve the layout.

However, the Track-Pull caught my attention because of a great publicity photo, the San Jose connection, and because - to be blunt - I was bored.

Track-Pull Tractors in front of Anderson-Barngrover. History San Jose collection.

The publicity photo, from History San Jose’s collection, shows a whole herd of Track-Pulls rolling in front of Bean Spray Pump on their way to the Southern Pacific freight house on San Pedro Street. It’s a great shot, both for the Track-Pulls and the Mission-style Anderson Barngrover headquarters in the back of the photo. When I saw the image a few years back, I knew I wanted to do something with that scene, and saved it away in a set of photos I keep around for inspiration.

Last month, I was looking for a little 3d printing project, and remembered those wacky Bean Spray tractors. “Huh, I wonder if I could 3d print one of these.”

Unlike some of the other models I’ve done, there’s precious little information available on the Track-Pulls, and only a few examples still in existence. (If I was smart, I’d also drive by a few lots around San Jose that have rusty farm machinery, just in case there's an actual Track-Pull tractor hiding nearby.) The nearest actual Track-Pull is at a museum up in the Sacramento Valley - reachable, but I'm not enough of a tractor fan to drive up there just to get measurements of a model.

I did a bit of searching on the Internet, turning up a few historical documents and a bunch of photos from the tractor restoration crowd. The best I found was an article from the October 30, 1919 issue of Motor Age, where the magazine reviews the tractor. Motor Age describes the Track-Pull’s engine portion as 30 inches wide, 43 inches high, and six feet long. The tricycle rear wheels were 66 inches apart (though a separate magazine review claimed it was only five feet wide), and the whole machine had a length of 110 inches. Beyond these rough numbers, there’s no other data on the Track-Pull apart from photos.

First part of design: tread

Full model

With the little information I had, I started trying to draw the Track-Pull. Like most of my models, I sketched my version of the Track-Pull in SketchUp. I used the rough dimensions, but eyeballed nearly everything else from the few photos.

To get started, I first modeled the Track-Pull in terms of rough shapes, and slowly refined and detailed the model. The caterpillar tread assembly was the first bit; I guessed at an overall size, drew its overall shape, then slowly added the treads and machinery. To increase my confidence, I printed out that assembly on its own just to prove that it could print, and so I could actually see the model in the flesh. (That's a nice aspect of having a 3d printer in my office - I can print out half-done models just for the encouragement, rather than having to send to Shapeways only when I've got a model that I'm willing to spend the money to print.)

Once I had the tread, I started roughing out additional parts of the model - first the gross details such as the outriggers, then the rough shape of the engine and radiator. I then started throwing detail on each piece, sort of how movie model makers throw on "greebles" - random detail - to make their models look more realistic.

Detail at front of model - node mount for fan bearing

This model was a good deal more complex than many of the models I've done for the model railroad. One trick was to work in terms of subassemblies. I used SketchUp's "group" command to make the larger assemblies (the tread, radiator, fuel tank, and outriggers) into single elements. When I needed to get to a hard-to-reach section of the model, I'd select the group that blocked access, and would move it so it was ten feet above or below the model. I could then move the part back into place easily.

I also added 3d parts for much of the piping, such as from the radiator to the engine and back. Normally, SketchUp has lots of problems with curved and round surfaces; having pipes intersect or turn right angles is particularly painful. Because many of these pipes were small (at most 2-3 inches across), I instead drew all the piping with hexagon shapes, and hand-edited the intersections between piping.

HO scale version

O scale version

For this model, I also printed the model in HO and in O scale both to see the detail and just for the fun of making a larger model. The HO model can print as one piece (with some extra supports to cut away); the O scale model had to be printed with the engine and tread as one piece, and the two wheeled outriggers as a separate part.

These models aren't complete and are still missing features. One obvious omission are the dual wheels for controlling steering and engine speed. As is, these are still impressive models.

Now, the Track-Pull isn't my usual sort of model to build, but it was a fun project. Better yet, it's a nice reminder how the 3d printer really broadens my modeling. Even a few years ago, my only choices for an orchard tractor would have been a die cast or plastic model (maybe one of those modern John Deeres I bought a while back), or else a detailed but pricey white metal kit such as any of the really nice Holt bulldozer tractor kits available from Rio Grande Models. 3d printing gives us the chance to get a wider selection of models.

Drawing those models also gave me the chance to find some interesting stories about how one particularly crazy tractor design came from San Jose. Crazy startups aren't just a 21st century creation of Silicon Valley.


Great thanks to the Flickr user who took pictures of the Track-Pull at the Hendricks Agricultural Museum up in Woodland.

Crazy Ideas in the Valley of Hearts Delight

Track-Pull Tractors in front of Anderson-Barngrover. History San Jose collection.

Out here in Silicon Valley, we’re a little crazy.

Well... a lot, actually.

We come up with crazy ideas: dog food delivered in bulk by drone. Uber for sharing underwear. Self-driving unicycles. Luxury chicken day care.

And, after all, it’s a tradition out here. We've been coming up with crazy ideas since the 1880's. We saw that in the past with stories of Victor Greco’s early adventures in the tomato paste business, Stanley Hiller’s apricot-pit charcoal gamble, or Johnathan Coykendall's prune coffee.

Or even Alfred Johnson's single footed tricycle-style caterpillar tractor.

Oh my, you haven’t heard about the Bean Spray Track-Pull?

At the turn of the century, San Jose had several businesses making farming equipment, all finding success by filling the needs for the orchardists and canneries filling the Santa Clara Valley. The Anderson Prune Dipper Company, Barngrover-Hull, and Knapp Plow are all well known. There was also the quite successful Bean Spray Pump Company, founded by John Bean back in 1884.

John Bean, the Steve Jobs of orchard spraying equipment.

John Bean was a prolific inventor, designing farm equipment and vehicles in the midwest. When he sold his design for a deep well pump for a significant payday, he decided to leave the midwest and find a climate better for his tuberculosis. He settled on an almond orchard near Los Gatos, prepared for a quiet retirement. However, like many gardeners, he quickly got frustrated with garden pests as scale infested his orchard. When he found that commercial sprayers were poorly designed and couldn't reach the tops of the trees in his orchard, he invented his own… and founded a new pump-making company in 1884. That company grew to produce many different sorts of machinery for agriculture.

The Crazy Startup Guys

By 1915, the Bean Spray Pump Company was a big, established company in the Valley, and its namesake inventor was long-retired. Just like today's big tech companies, Bean Spray had to search around for their inspiration for products to keep growing, either from folks inside the company, hiring new designers in-house (such as acqi-hiring engine design expertise by purchasing the Cushman company in Nebraska), or sometimes seeking help from some crazy startup guys.

The startup guys, in this case, were Alfred C. Johnson, James H. McCollough, and Fred D. Calkins. Alfred was the machinist and entrepreneur, Calkins the assistant, and McCollough apparently was the business guy.

Alfred Johnson had been quite the tractor entrepreneur. Although only in his mid thirties, he'd already convinced his family to join him in previous crazy tractor projects. The Johnson family, originally from Iowa, moved to Dixon (near Davis) before 1900. Alfred must have been quite the precocious engineer, for in 1907, the family appears in Sunnyvale (just after the arrival of the Hendy Iron Works in town.) Together, Alfred and his father started the Johnson Traction Engine Company, eventually pulling in brothers and assorted helpers to the cause.

Johnson Toe-Hold Tractor, built by Hendy Iron Works. Photo from Bancroft Library collection

Their first design, the "Toe-Hold Tractor", was a low-power, low-to-the-ground model suited for orchard work first sold in 1911. The Toe-Hold tractor's "secret sauce" were the fins on the wheel, particularly suitable for traction in wet soil. Alfred and his brothers originally prototyped the idea by welding horseshoes on a wheel, but the patented design used steel fins instead. The Johnson family sold the design to the Hendy Iron Works folks, which put the design into production in 1911. In 1913, Hendy shared the rights to the design with the Rumely Company from Indiana (but continued producing the tractor). Rumely claimed forty tractor sales as soon as they bought the design, even as they struggled to open their San Francisco sales office.

Johnson also designed a variant called the "Johnson Improved Tractor" for Hendy, (the recumbent bike of the tractor world). The Improved Tractor was similar to the Toe-Hold, but had additional sheet metal covering the motors, moving parts, and wheels, probably to avoid snagging tree branches in the orchard. Johnson, his father, and Calkins patented several of the improvements from their tractors in subsequent years.

Meanwhile, McCollough was just out of U.C. Berkeley with a degree in Commerce in 1904. He apparently was searching for his chance at great glory, but meanwhile worked various jobs, running a dry goods store in Sunnyvale and running the San Jose Roofing Company for a couple years (according to old city directories.) Johnson, McCollough, and Calkins must have met up around 1910 in Sunnyvale, and decided that designing tractors wasn't a bad way of life.

Yuba Ball Tread Tractor. From Yuba Construction Company catalog, Wisconsin Historical Society collection..

The new team decided to take a second crack at the tractor market. Together, Johnson, McCollough, and Calkins bought a patent for a "ball tread" tractor from Clarence Henneuse, a tractor designer working for the Best Tractor company in Oakland. Henneuse's design had simplified caterpillar tread design by using huge ball bearings between the caterpillar track and race. Although Best didn't think much of the design, our three heroes apparently saw its virtues. Johnson worked to make it practical and designed a transmission for the new tractor design. The three then pulled in some manufacturing help from Detroit, and built the "Calkins & Johnson Ball Tread" tractor, which outwardly resembled the early Best caterpillar tractors. The three ran a business selling them in San Jose for a very short time, but after a quick bankruptcy sold out to the Yuba Construction Company around 1913 which continued making the design.

Advertisement, Track-Pull tractor.

All these designs were large, bulky tractors. Their next focus was going to be quite the other way.

The Crazy Startup Guys Pitch Their Idea

In 1915, the trio took their next crazy idea to Bean Spray. "Orchards," the crazy startup guys said, "need small, light-duty tractors. Those caterpillar-style tractors are just the thing for orchards. But all the caterpillar-style tractors had two separate caterpillar treads - which seemed two times as much as any tractor really needs. Why not have a tractor with a single caterpillar tread?"

The Track-Pull tractor really did have all those features. It had a single caterpillar tread, and a tricycle-like rear body for the driver and to attach plows. The tractor was low-to-the-ground to move under the trees, and narrow enough to fit between orchard rows. The narrow and compact body was unlikely to snag on tree branches. It was lightweight and spread its weight so it wouldn't compact the ground under the trees. It could also turn on a dime, with a five foot turning radius.

Bean Spray Pump was convinced, and bought the idea; the new Track-Pull Tractor became quite the hit. The original model sold $419,000 in tractors in 1916, and $723,000 in 1917 in 1917; the photo of the Track-Pulls driving from the Bean Spray Pump plant to the Southern Pacific's freight station at San Pedro Street represents some of those sales. The era's equivalent of Consumer's Reports describing it as appropriate for two or three plows, and farms less than 160 acres.

The initial models had a four-cylinder engine mounted on the right side of the tractor, and a radiator on the opposite side, making for a boxy appearance even as the tractor balanced on its single tread. The initial Track-Pull was the 6-10 model (6 hp pulling, 10 hp on the tread), but the company eventually made models ranging from 10 horsepower to 32 horsepower. Regardless of the strangeness of a single-footed caterpillar tractor, Bean Spray sold these tractors through at least 1921, showing that crazy ideas could still be profitable.

Can't Take the Tractor Out of the Tractor Designer

McCollough, Johnson, and Calkins each took their own path after the Bean Spray purchase.

Fred Calkins apparently took the quiet way out, appearing as an orchardist in Sunnyvale from 1919 on; the 1920 census shows him as a fruit buyer, living with his sister and brother in law on Murphy Ave. By 1940, Calkins was President of the Santa Clara Valley Fruit Exchange, and living on Alta Vista Way in San Jose's eastern foothills (as if there were ever a better address for a startup guy.)

McCollough and Johnson both joined Bean Spray, and each took a different path with the big company.

Johnson continued, now with the title "mechanical engineer" at Bean Spray and later Anderson-Barngrover through at least 1926. In 1945, patents with his name on them were still being filed by Food Machinery Corporation.

Although McCollough was working for Bean Spray Pump Company in 1918 when he registered for the World War I draft, he was a bit... detached... from his job in Big Tech. He listed his occupation as "fruit ranch proprietor, also promotor and head of Tractor Repair, Bean Spray Pump Co." He was also still living with his mother at 57 South 19th Street, on the unfashionable side of Coyote Creek.

By 1919, McCollough cut out of the big company, listing himself as a "machinery promoter" on his 1919 passport application and "promoter, traction engine" in the 1930 census. City directories from 1922-1925 show McCollough continued working on tractor designs out of an office in the First National Bank building. Soon after, he switched to real estate.

The tractor bug bit both men again; in 1935, McCollough and Johnson again pushed a new design called the "Unitrack". The new tractor had a family resemblance to the Track-Pull, but with a solid body that suspiciously resembles a Jawa Sandcrawler from Star Wars. Its small size and low price certainly would have been handy in those post-Depression days. The new tractor shows up in ads in the Santa Cruz Evening News in May of 1938:

Farmers Attention: Before you buy any small tractor on which you can ride, investigate the new Unitrack tractor, the most complete track laying tractor of its kind. Very economical in operation. Price $495.00 plus tax. Demonstration given. Kroneder & Son sole agent, Glen Canyon, CA. [near Santa Cruz]

By April 1942, when McCollough registered for the World War II draft, he was living in Santa Cruz while working for the Irving Lee & Co. investment company back in San Jose. Johnson, always looking for interesting things to design, was in Long Beach, designing and building airplanes, but continued consulting and designing for FMC, Bean Spray's successor. "Alf" Johnson died with his boots on; he died in 1954 while field-testing a new tractor in Sunnyvale.

Five designs, three designs purchased by large companies, one fire sale, and one bankruptcy. Not bad for a set of crazy Silicon Valley tractor entrepreneurs.

Next time:3d-Printing a Bean Spray Pump Track-Pull.


Photo of Track-Pulls on a rampage on Santa Clara Street comes from History San Jose, and dates to around 1917. Thanks to the many tractor enthusiasts who have written about the Track-Pulls over the years, especially September 1985 Gas Engine Magazine. Bill's Page supplied much of the history of Johnson, McCollough, and Calkins's tractor startups.