ONLY ONE BUILT! Built in Caterpillar’s own shop by a Cat tool & die maker (German craftsman employee), fabricated of sheet steel, steel bar stock, and some undercarriage components of wood on rubber tires, Bed raises, doors open, Firestone rubber tires, 34”L x 15”T x 18” W weighing 75 lbs. Featured in a 3-page article and on the cover of August 2002 Toy Trucker & Contractor magazine. Special mold fabricated by Goodyear to make tires. Some paint is coming off in the bed

Caterpillar 779 Off-Highway Truck Model Description & History

This is a one-of-a-kind, hand-built, 1/10th scale precision model of a 75-ton capacity Caterpillar Model 779 OHT (off-highway truck). This model was built in Caterpillar's own shops by a Cat tool and die maker who spent about 1,000 hours or around a half of a work year building it 59 years ago back in 1963. It appears to have been fabricated mostly from steel sheet material and steel bar stock with some undercarriage details in wood along with real rubber tires. This huge model measures 34" long by 18" wide and 15" tall with the box in the down position.

This fine model could be the centerpiece of your entire Caterpillar, tractor, or toy truck collection. It dwarfs the pop can sitting beside it in the first photo as well as the Tonka dump truck shown beside it in the second photo. It weighs 75 pounds without the plywood display base shown in the sixth photo. Also included is a special plywood cover with the name CATERPILLAR stenciled on the top used to protect this gem during storage and transport.

There are several reasons that make this a very special model. They include but are not limited to the following:

1. This is a huge precision model with much intricate detail and it appears to be extremely well made

2. This model is special enough to have been featured in a 3-page article and on the cover of the August
2002 issue of "Toy Trucker & Contractor" magazine

3. There is also a several-page follow-up article on this gem in the March 2018 issue of "Toy Trucker &
Contractor" magazine

4. A very skilled tool & die maker worked about 1000 hours or about a half of a man-year to build this
gem from scratch

5. This model was an "in-house job" that was built by Caterpillar in their own shop. They built the full-size
OHT (off-highway-truck) vehicles later on

6. This exceptional model was used to promote the design and acceptance of the huge truck to the
management people at Caterpillar before production began

7. A special mold was fabricated by Goodyear to make these 6 unique and very detailed tires that most
  likely were never used on another model
8. This model is a "1 of 1" in the whole world and no others like it were ever built by anyone
9. About $10,000 of time and money in 1963 dollars were spent on its construction which might equal
$80,000 to $100,000 in today's dollars due to inflation

10. Most likely, no other collectible Caterpillar-related items other than their full-size crawler tractors are
as interesting, as historically significant, or are potentially as desirable as this model is

11. Caterpillar would like to forget this unsuccessful part of its history which is kind of like the
unsuccessful Dain tractor in John Deere's tractor history

12. This is the most significant remnant of the 779 OHT product line since all 41 of the full-size trucks
produced were recalled and scrapped by Caterpillar
Most of the following information is from an extensive article on this model featured in the August 2002 edition of "Toy Trucker & Contractor" magazine. This article was written by Richard Guhl who worked for Caterpillar in the following capacities:
1955 Richards Guhl joined Caterpillar
1966-1990 OHT (Off-Highway Truck) Design Supervisor
1990 Richard Guhl retired
Richard Guhl's wonderful article lists the following features and historical information regarding this fine model:
CAT 779 TRUCK MODEL by Richard Guhl
1. Model was built around 1963 in Caterpillar's own shop in Peoria Illinois.

2. Built by the Technical Fraternity at CAT for internal promotion to top corporate officers and the Board
of Directors.

3. Believe model was built by a German craftsman employee for about $10,000. Only this one model
was built.
4. Model is 1/10th scale.
5. Model is nearly all-metal construction except for the six 9-inch diameter rubber tires (special mold
made by Goodyear for these tires) and some internal module components made from wood.

6. Sales Model -779, Engineering Model - RM233
7. Dimensions and weights:
Height 15 inches
Width 18 inches
Length 34 inches
Weight 75 pounds
Color Highway yellow
Features:
Single tires on the front axle and duals on the rear axle
Wheels Rotate
Front wheels steer
Chassis is supported on springs
Dump body raises to dump position while rear tailgate automatically opens
Cab doors hinge open and latch shut
Steering wheel rotates
Model Details:
Fuel tank
Hydraulic tank
Electric traction component air cooling intake
Steering system components
Rear axle control members
Hoist cylinder
Diesel engine and generator modules
Oil suspension struts, front, and rear

FULL-SIZE VEHICLE DATA

Engine - D348 @ 2000 RPM and 960 Horsepower
Electric Drive
85 Ton load capacity
Start of productin date - 10 November 1966
Start serial number - 45H40
End of production date - 23 May 1969
Stop serial number - 45H80
Total production - 41 units

OTHER ITEMS OF INTEREST INCLUDED WITH THIS MODEL
:
Specification sheets available:
Dated July 1967
Dated September 1968
CAT "BLADE" newspaper dated 5 Nov 1965 announces the introduction of 779 OHT
CAT parts book for 779 truck published July 1968
Author (Richard Guhl) signed book "Caterpillar Chronicle" published 2000 talks about CAT 779 on pages 77
through 80
Heavy-duty wood carry and storage box has been reworked and repainted
The "779 Story" written by one who was there (Richard Guhl) is included and reproduced below :

THE STORY BEHIND THIS MODEL by Richard Guhl

"It was in the mid -1950's when Caterpillar, in East Peoria, Ill., launched its efforts for the design of a family of off-high-way trucks (OHT). While the work started in the mid-1950s, the first model the 769, with a 35-ton payload, was not ready for production until January 1963, about eight years later and after several hand-built concepts had been tested and rejected.

   The long delay to the first production was due to the fact that many middle and senior-level company managers did not want to be involved with the design of a new product line that had an uncertain future. They were traditional Caterpillar men, whose positions in the company were a result of many years of earning their stripes in a firm where experience was the prerequisite to advancement. They were talented men, capable and comfortable making decisions for the "meat and potatoes" products for which CAT was the recognized worldwide leader. But they had little time for the added burden of this stepchild. The new off-highway truck design group was not given the needed direction and support by the company.

Some members of the board of directors recognized that there was a tremendous future in the off-highway-truck business, and that CAT was losing out to others who were making the most of those opportunities. They recognized that trucks were the obvious trend in the mining and construction business, and they were frustrated at the slow pace of progress being made at their company. As time went on, they became very vocal about getting the show on the road, and they were putting pressure on the top administrative officers to that end.

In 1961, the year of "the great electrical conspiracy," a price-fixing and bid-rigging fiasco, a number of high-level executives lost their jobs at General Electric and became available for top jobs elsewhere. One of those executives was hired by Wabco, Westinghouse Air Brake Company (formerly the R. G. LeTourneau Company), Caterpillar's neighbor across the Illinois River in Peoria. A number of associates came along with that executive, crowding the upper-level managers at Wabco.

Shortly thereafter, CAT hired the former president of Wabco, and he brought along a solution to the problem of the slow pace of development of the OHT program at his new place of business. As a result, the then president of Caterpillar hired a man from Wabco, who brought along several other engineers, whose group was developing that company's line of off-highway trucks. Since he was hired by the president of Caterpillar, the new man had full rein to run things his way with little interference by other high-level CAT managers, including those in Engineering and the Test and Evaluation Divisions. His assignment was to develop an OHT in the 75-ton capacity range and to include the latest technology. Its model designation was to be the Model 779.

His philosophy was to build the machine as light as possible (to increase the payload to tare weight ratio), and if Proving Ground and field test experience exposed shortcomings, to work with customers on their job sites to try out the necessary changes and corrections. This approach was common among smaller competitors, where often the first hand-built machine had to be sold to keep the company solvent. Customer expectations of the ruggedness and availability of CAT machines are often higher than the competition. But in the case of the 779, testing was not rigorous enough to meet those durability requirements. Nothing was allowed to retard the program schedule.

At that time, the culture at CAT was that, while it was often not the first to be in production with a new family of vehicles, it proved the worthiness of its machines in its own backyard before selling them, with extended testing and with fixes in place before releasing to production. CAT aimed for having the world's best machines, and as much as possible, proven and ready for the marketplace with excellent availability and supported by unsurpassed service. This approach usually resulted in market dominance after a few years of production. Initial vehicle costs were often higher than others, but over the long haul, the CAT machines put a lot more money in the customer's pocket than did those of the competition. That demands a well-organized system of independent checks and balances to achieve the best product. The difference in culture began to show.

The new machine had a CAT-designed electric power transmission system, including a generator attached to the rear of the Diesel engine, traction motors located inside the rear axle housing, and the switching gear and component cooling systems. It was intended to challenge what General Electric was selling to the competition. The 779 used the D348 engine, running at 2,000 RPM, set at 960 horsepower and the vehicle had a rated payload capacity of 75 tons. Production started on November 10, 1966, with serial No. 45H40 and continued until May 23, 1969, with Serial No. 45H80. Total production was 41 units. The company provided total vehicle support to the customers, including both parts and manpower. The customer was essentially risk-free in this situation, and unless failures caused a loss of production, he was in a very good position.

After about 2-1/2 years, production was stopped. Major problems with the electric traction system, the main frame, and other high-cost areas resulted in a deteriorating reputation for the vehicle and the inevitable loss of interest by the marketplace. Also, the company could not see light at the end of the tunnel where warranty costs were out of control.

Sometime later all of the machines that had been shipped to the field were cut up with torches and a large expense was incurred in scrapping tooling and new material in the supply pipeline.

The model of the 779 that is available today has always been understood to have been built by a Caterpillar employee, a German craftsman in Peoria, in or about 1963. This large, one-of-a-kind, hand-built tenth-scale model, was rumored to have cost $10,000 at that time, Never before or since was a similar model built of any CAT Off-Highway-Truck. It was built under the direction of those managing the program and was intended to sell the company on their credibility as designers and to promote funding and support by top corporate officials and the board of directors. The model was transferred to the Decatur Plant when the design function of that vehicle was moved there in 1966. It served the purpose for which it was built, and after many years it was given to the author since he was the senior employee still working in the OHT division who had been involved with the 779 project.

Meanwhile, the 773 OHT had been designed and introduced at the Decatur plant by the local engineering group. It was a 50-ton capacity mechanical drive machine and fell into a size class between the 769 and the 779.

Then in May of 1975, the first production 777 OHT was built in Decatur after it had been designed by the engineers at that plant. Also a mechanical drive truck, it was one of the most successful Off-Highway Trucks ever introduced, with excellent acceptance around the world. It was reliable and tough, it had great design balance and with its good availability, it made a lot of money for a lot of people. Thousands of these machines were built, and updated versions of this model continue in production at Decatur to this day (written in 2002).

The design of the very successful 777 machines profited from the experience gained, both the successes and the failures of the 779 vehicles. Then too, many internal controls were put in place and strictly adhered to, after the 779 experience, to monitor and review the development and introduction of all new CAT products. These contributions turned out to be the best legacy of the 779 program."

Well, what an interesting history of CAT's first production Off-Highway-Truck !! Now on to some more observations of some of the special details on this truly exceptional model truck:

SPECIAL FEATURES OF THIS MODEL TRUCK

Very few promotional models exist today that were built by manufacturers in their own shops. Some of the various salesman's sample models might qualify as being made by the manufacturers. The half-size Reo car called the "Baby Reo" that Reo built in its own shop in the early 1900s would definitely qualify as being built by the manufacturer.

According to the history listed above, a German tool & die maker spent around 1,000 hours building this model. At 40 hours per week, that would have taken 25 weeks or a half of a year of work time to build. If one assumes that shop time in a large company's shop today costs them around $100 per hour, a model like this might cost at least $100,000 to build today. That estimate is making no allowance for materials which would be insignificant compared to the labor cost anyway. However, that materials cost assumption is ignoring the cost of the mold to make the rubber tires.

The six 9" tall tires are no amateur job made from soft silicone RTV rubber. They are rather hard with great detail in the lugs and sidewalls and are accurate models of full-sized tires. They have the name "GOOD YEAR" with the famous Wingfoot image in the middle of the word "GOODYEAR". They also have the term "HARD ROCK LUG XT" on them as well as the typical Goodyear diamonds on the sidewall where it meets the tread. One could expect to pay at least $10,000 for such a precision rubber mold today. That would put an estimate to build a model like this today at around $110,000.

There is one special feature on this model that impresses nearly everyone who sees it close up. Both of the doors on the cab are functional with double hinges and working spring-loaded latches. The doors have steps around the outside that correspond to the opposite steps in the door jambs. One can give an open door the slightest push and it will close smoothly with a light "click" sound. That feature is almost as impressive as the fit between the outside of the door and the inside of the cab door opening. That gap is minimal, at about .020" all around, and is very consistent. This type of craftsmanship is typical of the work done by a tool & die maker in a large manufacturing facility back before the days of CNC machine tools. Please notice that the interior of the cab is painted gray rather than yellow.

The amount of detail on the box is amazing as well. It is kind of like a work of art due to the complexity of the reinforcing ribs and perimeter supports. This box appears to have been made up of pieces of sheet steel material to which steel reinforcing ribs were attached. Perhaps those ribs were attached using a silver solder or silver brazing process. At the back of the box, one can see the linkage that makes the bottom-hinged tailgate open and close automatically as the box goes up and down. This is an exceptionally nice detail that took a lot of time and effort to make work as smoothly as it does.

The chassis is very detailed with 4-wheel spring suspension accurately simulating the hydraulic suspension used on the full-sized trucks. A hydraulic cylinder at each corner was fed with oil from an accumulator that held a reserve of oil under pressure that was most likely charged with nitrogen gas under high pressure. The bottom view of this model shows some of the detail in the steering system. A center-mounted bell crank actuated by a pair of hydraulic cylinders transmits forces through a pair of tie rods that run to each of the front steering knuckles that support the front wheels.

The engine in this model is a wooden model of the famous CAT D348 which was a 1,786 cubic inch displacement V-12 with twin turbochargers and after cooling. That engine drove a large electrical generator which is a round feature also made out of wood on this model. Electrical power flowed to a pair of electric traction motors located inside each rear wheel. There was no differential on the 779 as there would have been on almost any mechanically driven truck. The twin electric traction motors on this model are also made out of wood. These motors drove planetary gear reducers in each rear wheel on the full-sized truck.

The size of the tires on the full-size truck is 21 x 49 which would be a 21" tall and wide section on a 49" diameter rim. They measure 91" tall so that is why the tires on this 1/10 scale model are very close to 9" in diameter. There is a detailed grille that covers the twin radiators that have pusher fans in front of the radiators rather than fans behind the radiators. The full-size truck has a 220-gallon fuel tank at the rear and a 59-gallon hydraulic oil tank under the box and this model has corresponding tanks as well.

It is interesting that the cab has windshield wipers and a hot water cab heater with no provision for air conditioning. No farm tractors came with factory air conditioning when this model was built so one should not be surprised that this model has no provision for cab air conditioning. The detailed seat has no functioning suspension under it. The engine in the full-size truck is started by using a 24-volt battery pack to make the traction generator act as a starter.

It would have been nice if the model builder had used model hex head screws rather than slotted round head screws but nobody should ever change them out. To do so would be like messing with the Mona Lisa. The tool and die maker that built this model probably had no idea of the scale fasteners available to the model engineering crowd back in the early 1960s. As you can see, there are some paint chips in various places on this model. The majority of the paint loss is on the piece of corrugated galvanized sheet metal at the front of the box where the box covers the cab.

An original CAT parts book that includes wiring diagrams belonged originally to Richar Guhl and is included with this model. The following provenance applies to this model:

1963 built by the Caterpillar Tractor Company's machine shop in Decatur Illinois

1990 CAT gave to Richard Guhl when he retired

2002 Richard Guhl consigned to Aumann Auction August 17, 2002 - sold to a toy and model collector in
Pennsylvania

Feb-Mar 2016 displayed at York Pennsylvania truck show

January 19, 2017 son of deceased Pennsylvania collector delivered to Bob Woodburn in Bozeman MT

Jan 20-22, 2017 Bob Woodburn displayed at Great Falls Montana farm toy show

One could build a special base to display this gem on that has 4 pairs of rollers, one pair under each wheel or pair of wheels. Those rollers could be motorized to make the wheels on this model rotate to make it look like it is moving. One could also make the front pairs of rollers steer to make the front wheels steer. One could also include an actuator that will remotely raise and lower the dump box. This would make this gem a real knockout at shows.

This might be the only chance you will ever have to own this one-of-a-kind model. If you have an extensive toy truck collection, promotional model collection, salesman's sample collection, or full-size Caterpillar construction equipment collection, you might do well to give some very serious thought to purchasing this model while you can.