The future of the foundry was 'cast' in the past. (2002 Charles Edgar Hoyt Memorial Lecture).

This year's AFS casting congress hoyt lecture details the importance of training and provides a first-person account of how the knowledge of the past must be communicated to today's foundries.

Charles Edgar Hoyt had a passion to teach, educate and train the individuals who work in foundries, supply products to foundries and purchase castings from foundries. He was the cornerstone of the American Foundry Society. It was his vision to organize foundries so they could share and develop new technology ensuring that the industry would grow and prosper.

The knowledge and accomplishments of Charles Hoyt and other foundrymen like him have--and continue to--influence the future of this great industry.

In this summary of the Charles Edgar Hoyt Memorial Lecture presented at the AFS Casting Congress in May, the message is that it is critical to empower today's metalcasters with training as well as the knowledge of the foundry generations of the past.

Metalcasting Past vs. Present

The quality of the castings that can be found in museums is impressive. The level of expertise needed to create them seems hard to believe when it is considered that ancient foundrymen did not have mullers, mixers, chemical binders, abrasive blasting equipment, pneumatic cleaning tools, sand and metal analytical equipment, and the vast technology available today through reference books and libraries. These foundrymen had to have a complete understanding of the basics of molding, coremaking, melting and pouring to produce high quality castings.

The oldest known casting in existence is a frog that was found in Mesopotamia and cast around 3200 B.C. This casting is currently on display in a museum in Shanghai. The first foundryman would not begin his career by casting an art object with radical parting lines and difficult metal flow characteristics. Prior to this level of metalcasting technology, primitive man most likely began by pouring simpler castings, such as arrow heads and spear points in open top, sun hardened clay or stone molds.

Although the castings of arrowheads and the frog show an evolution of the casting process, neither are extremely sophisticated. One example of a much more sophisticated and larger casting is the Colossus of Rhodes, one of the seven wonders of the ancient world. A statue of Apollo believed to be constructed around 290 B.C., it stands with one foot on each side of the harbor of the Island of Rhodes. This statue was a collection of castings assembled to form one 105-ft tall casting, weighing 720,000 lb.

How did the foundrymen of 250 years ago cast wood-burning stoves that are structurally sound and have casting finishes rivaling those produced today without today's technological resources? They used naturally bonded sand to form the molds. This sand occurred on the banks of rivers and could contain up to 25% clay. This naturally bonded sand contained moisture (typically 7%) and combustible agents from the decomposition of the trees and overburden. It was shipped to a foundry without drying and after minimal scalping to remove foreign materials.

Since the clay content of this sand was exposed to 50,000 yr of freezing and heating, the moisture had been deeply absorbed into the clay's structure. The sand could be placed in the foundry and would retain its moisture for weeks. Since this was a sedimentary type deposit, the sand was typically very fine, providing excellent casting finish.

Today's foundries replace 50,000 yr of tempering with a three-minute muller. Typically, sand can be reused 10-20 times in a day and often is hot when the water is mulled into the clay platelets.

A vertically parted molding machine can produce 500 molds/hr with one machine operator. Controlling the sand's properties becomes more critical as the systems become faster and tolerances are reduced. Today's technology is all based off of the same knowledge foundry men have gathered for years.

Passing on Knowledge

If past foundrymen didn't have access to reference books, how did they pass on their knowledge to the following generations? The answer lies in a practice that most current foundrymen have abandoned: the apprentice program. In the past, the foundry industry was considered an excellent trade. New employees would work through a long and extensive training program and were tested prior to being considered a journeyman foundryman.

Many foundrymen were paid only for quality castings, so they took the time and care to check the pattern, check the sand and temper it with water, riddle the sand, ram the mold, cut the gates, vent the mold remove any loose sand, close the mold and pour the castings. Complete knowledge of what was required to make a saleable casting was essential if the foundryman was to receive his paycheck.

Today it is difficult to attract high-quality personnel to entry-level foundry positions. This difficulty leads to casting quality problems. When the unemployment rate was at 4%, I was asked by a foundry for insight regarding a scrap problem. This foundry typically had a scrap level of 2-3%, but it had suddenly jumped to 14%.

The most obvious question was to ask what had changed. Since the increase in scrap rate, however, his laboratory data didn't reflect any changes in the properties or practices for the sand and metal process.

The following day the foundry assembled the supervisors and asked them if they were aware of any changes that had occurred. After the first two supervisors stated that they weren't aware of any, the cleaning department supervisor stated that he had many new employees without proper training.

The group visited the cleaning area and began checking castings in the scrap bins. The untrained employees were discarding castings that could have been saved with minimal time and effort. After examining the castings, the foundry determined that it still was running at 2% scrap. A series of classes were begun to train the new employees.

This example confirms the adage that "we never have time to do it correctly the first time, but we always have time to do it again."

When individuals are assigned to a new job today, they typically receive an overview of the foundry operation but are not provided with the in-depth training that would make them more effective employees. When an employee doesn't understand the operation, he tends to experiment and personalize it by making small changes and waiting to see if anyone complains. If no complaints are received, the process can make a gradual change from an excellent operation to a good operation to an unacceptable operation.

Learning the Hard Way

The first day I worked in the foundry, I was assigned to an old molder named Bernie who told me that "if you pour iron on water, it will explode." When I asked why, he said, "it just did." I went back by the cupola and poured 0.25 in. of water in a pig mold and poured some iron on top. Bernie was a lot smarter than I thought--the iron shot up two stories high. I found out that most of the molders knew what would happen but none of them knew why.

The reason is that water expands 1600 times it's volume when it is converted to steam. Since this expansion is taking place under the molten iron, the iron was propelled away from the water at an astounding rate.

Twenty years after the iron-water experiment, I was sent to South Korea to help with the start-up of a large steel foundry. The castings were to range from 100-150 tons and were to be poured into pits lined with nobake molds and cores. The plant was near a harbor and the pouring pits were 40 ft deep.

These conditions resulted in water seeping into the bottom of the pits. I explained to the plant superintendent that we needed to repair the pits and stop the water flow. The superintendent said that he thought we could put some dry sand in the bottom and that I shouldn't worry. I then explained that unless he wanted his foundry in North Korea, we had to eliminate the water. The pits were repaired.

Educating Employees

How can employees begin to understand the basics well enough to enable themselves to expand their knowledge to encompass the entire foundry operation? How many employees know why green sand is called green when it's really black?

Foundries can provide training that is designed to move the student in gradual steps, and with thorough understanding, from a current level of knowledge to a level where the employee can work more effectively, efficiently and with confidence. It is up to the foundrymen to take pride in their work and capitalize on the training opportunities that are available.

Knowledge stems from technology and education and leads to great savings. If metalcasting history, technology and technical support is the backbone of the industry then pride must be the heart. When employees can take pride in their job--and be recognized for accomplishments--the foundry has a win-win situation.

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RELATED ARTICLE: Daryl Hoyt's Career

Over the span of Daryl F. Hoyt's s 40-yr career, he has worked as a foundry lab technician, director of technical services, vice president of technical services and vice president of research and development. He is currently president of Foundry Sand Technology, Marseilles, Illinois.

Hoyt was awarded the AFS Service Citation in 1985, the CMI Director's Award in 1988 and the Thomas W. Pangbom Gold Medal in 1997. He also has been a contributing author to numerous technical articles that have been published by AFS and other trade organizations.

Hoyt served in the U.S. Air Force, achieving the rank of E-9, Chief Master Sergeant. He was awarded the USAF Commendation Medal and the USA Meritorious Service Medal.