the seven wastes Archives - CNC Industries

Precision Aerospace Machining and the Seven Wastes of Lean (Part 3)

In continuing on the Lean Journey, we will talk about the third of seven wastes: Inventory. Historically, inventory was not considered a waste. Large batch manufacturing was a necessity at the beginning of modern machining and manufacturing. Inventory stocks were considered healthy as they indicated that a business could ship to their customers quickly. The story of Inventory becoming considered a waste starts in post WWII Japan. Japan underwent a transformation in their productivity and processes after WWII and began to compete well on the world market. Unfortunately Japan does not have the land area that America does, and therefore the cost of holding inventory was much greater – due to the higher property costs, etc. Toyoda quickly realized that smaller batches, when made efficiently, lead to lower overall costs than large batches do.

In a precision aerospace machining environment, a balancing act is needed. Since CNC Industries machines a large variety of precision parts we cannot afford to have a specialized machine for each part or process that we do. Small machine shops also do not have the luxury of a rolling assembly line between our machines. With these restrictions, and the large amount of processing and manufacturing time that it takes to make a single aerospace part, we are put into a more difficult position that a production facility. We cannot truly operate with no inventory as the goal would be, so we must decide on the ideal inventory to keep on hand.

Precision aerospace machining processes typically have rather long setup times relative to simpler machining processes. This causes the ideal batch size to increase in order to compensate for the lost time on the machine while it is down for setup. At CNC Industries we have worked long and hard to decrease our setup times and have successfully lowered our setup time by 75% over the last 5 years. This has enable us to lower the ideal batch size as well, which in turn allows us to hold less inventory.

In addition to the setup process improvements that we have made over the years, information management is key to efficiently running small batches. Smaller batches will mean more switchovers, more setups, and more jobs running at the same time. With all of these issues, scheduling is both critical and difficult. Job Manager II allows us to have a visual reference of the schedule at any computer throughout our facility and quickly identifies and problems or potential problems at an early stage of the process which allows us to quickly make any necessary adjustments.

June 7th, 2010|Tags: Aerospace Machining, Custom Machined Parts, inventory, Lean Manufacturing, Precision Machining, the seven wastes|

Precision Aerospace Machining and the Seven Wastes of Lean Manufacturing (Part 2)

In continuing on the topic of lean manufacturing in an aerospace machining environment today I will look at how CNC Industries handles the second waste identified in lean manufacturing. The second waste is typically identified as unnecessary transportation. At CNC Industries we look both at internal and external transportation as areas that can cause waste.

The costs of external transportation (shipping) are easy to identify. With external transportation we can easily see the cost of the transportation in dollars as we receive bills from the shipping companies. Any extra shipments obviously incur additional charges and it becomes important to keep the number of shipments required to an absolute minimum. To facilitate this we often work with our outside vendors to have our parts shipped directly from one vendor to another in the case that we have multiple outside operations back to back. As often as possible we find outside vendors that handle multiple processes to save both on the cost of production as well as the cost of transportation. In addition our AS9100 compliant procedures for selecting and purchasing from our vendors allows us confidence in the quality of the parts that we have outsourced.

Internal transportation costs are often more difficult to quantify. Many times companies will both start and stop their efforts on cycle times and overproduction as I talked about in the prior post. Transporting the parts internally more than necessary is also a form of wasted efforts. The cost of moving the parts throughout a facility may seem minor but all forms of transportation take up time and do not add anything to the value of the part. In addition every time a part is moved it is another chance for the part to become lost or damaged.

Extra transportation can occur due to a number of factors in the manufacturing process. If the parts were not scheduled correctly they may need to be moved aside to allow a different part through the machine. Poor routing of the operations that the part takes through the manufacturing process may mean that a part is scheduled through machines that are far apart in the factory. Poor engineering of the part machining process itself may mean that the part has more machining operations than necessary. Any of these items may add additional internal transportation and raise the cost and potentially lower the quality of the part.

Our ERP System – Job Manager 2 – allows us to schedule our parts with confidence that they are engineered and routed correctly. In addition to the initial engineering and routing we have a comprehensive corrective action system and Process Change Request system that allow us to continually improve our processes. Each time we manufacture a part we are able to review and adjust the process and operations as necessary to make the parts even better and more efficiently than the last time.

Aerospace machining and the high mix / low volume work that comes with it creates additional challenges in scheduling. Our engineering processes are designed to quickly work through the numerous issues with new parts and smaller batches. Our scheduling module in Job Manager 2 has a visual scheduling board that allows us to quickly determine the best routing of each part and quickly determine any problems with the processes involved. Job Manager 2 also allows us to analyze each part and quickly find any areas that have lower efficiency so that we may quickly focus our efforts in the appropriate places.

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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.

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May 14th, 2010|Tags: Aerospace Machining, Lean Manufacturing, Precision Machining, the seven wastes, transportation|

Aerospace machining and the seven wastes of lean manufacturing pt2

Due to a few issues on renaming the old post I am repeating the original post with the original title.

In continuing on the topic of lean manufacturing in an aerospace machining environment today I will look at how CNC Industries handles the second waste identified in lean manufacturing. The second waste is typically identified as unnecessary transportation. At CNC Industries we look both at internal and external transportation as areas that can cause waste.

The costs of external transportation (shipping) are easy to identify. With external transportation we can easily see the cost of the transportation in dollars as we receive bills from the shipping companies. Any extra shipments obviously incur additional charges and it becomes important to keep the number of shipments required to an absolute minimum. To facilitate this we often work with our outside vendors to have our parts shipped directly from one vendor to another in the case that we have multiple outside operations back to back. As often as possible we find outside vendors that handle multiple processes to save both on the cost of production as well as the cost of transportation. In addition our AS9100 compliant procedures for selecting and purchasing from our vendors allows us confidence in the quality of the parts that we have outsourced.

Internal transportation costs are often more difficult to quantify. Many times companies will both start and stop their efforts on cycle times and over production as I talked about in the prior post. Transporting the parts internally more than necessary is also a form of wasted efforts. The cost of moving the parts throughout a facility may seem minor but all forms of transportation take up time and do not add anything to the value of the part. In addition every time a part is moved it is another chance for the part to become lost or damaged.

Extra transportation can occur due to a number of factors in the manufacturing process. If the parts were not scheduled correctly they may need to be moved aside to allow a different part through the machine. Poor routing of the operations that the part takes through the manufacturing process may mean that a part is scheduled through machines that are far apart in the factory. Poor engineering of the part machining process itself may mean that the part has more machining operations than necessary. Any of these items may add additional internal transportation and raise the cost and potentially lower the quality of the part.

Our ERP System – Job Manager 2 – allows us to schedule our parts with confidence that they are engineered and routed correctly. In addition to the initial engineering and routing we have a comprehensive corrective action system and Process Change Request system that allow us to continually improve our processes. Each time we manufacture a part we are able to review and adjust the process and operations as necessary to make the parts even better and more efficiently than the last time.

Aerospace machining and the high mix / low volume work that comes with it creates additional challenges in scheduling. Our engineering processes are designed to quickly work through the numerous issues with new parts and smaller batches. Our scheduling module in Job Manager 2 has a visual scheduling board that allows us to quickly determine the best routing of each part and quickly determine any problems with the processes involved. Job Manager 2 also allows us to analyze each part and quickly find any areas that have lower efficiency so that we may quickly focus our efforts in the appropriate places.

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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.

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May 14th, 2010|Tags: Aerospace Machining, Lean Manufacturing, Precision Machining, the seven wastes, transportation|

Precision Aerospace Machining and the Seven Wastes of Lean Manufacturing (pt1)

As I talked about in the last post, I will be examining the seven wastes identified in lean manufacturing and showing how CNC Industries handles each in a high mix / low volume aerospace machining environment. The first of the seven wastes is Overproduction. Overproduction is using more resources than necessary to create and deliver a part to the customer. Overproduction can be further defined as producing more, sooner or faster than what is necessary. Elimination of overproduction is a large factor in Just-In-Time systems that many manufacturers are focusing on. Just-in-time has a goal of eliminating inventory and producing or ordering material to arrive just in time for the operation that it is needed in.

Batch size is a large factor to consider when looking at overproduction. It is important to not produce too many parts – this leads to storing the excess parts in inventory for an excessive amount of time. However, in an aerospace machining environment the complexity of the parts is prohibitive to a true just-in-time system. When a part may take 6-8 weeks to manufacture and only a small amount of the parts are needed each week to create a new batch for every shipment would necessitate setting up a new batch each week and having multiple batches open at the same time. The logistics of tracking all of these batches combined with the costs and time of setting up a machine each week for the same part would be prohibitive. In addition to the setups and the logistics, material orders would necessarily be smaller and more frequent which would eliminate cost savings in ordering and require more time in purchasing and receiving material. Of course a production facility can avoid many of these pitfalls by having specially made machines that are dedicated to a certain process or part. In a high mix environment, machines tend to be needed for many different parts and cannot be dedicated to a select group of part.

Instead for a high-mix low volume aerospace machining facility, selecting the right batch size includes factoring in the setup costs and the lead time to create a batch that is a reasonable multiple of an individual shipment. In the above example it may be seen that a batch that is the equivalent of 10 weeks of shipments is the optimum size to reduce overproduction and minimize inventory storage time as well. The key is to account for holding costs, batch setup costs, and the estimated demand on a given machined part. Our ERP system, Job Manager 2, has a module to handle these calculations and give a suggested batch size in order to lower the overproduction to the lowest feasible amount. Selecting the right batch size is of paramount importance in attempting a lean operation in an aerospace machining environment that tends to have high mix and low volume production.

CNC Industries solves the problem of overproduction waste through efficient information handling and analysis. We have strong visualizations of our production and inventory and we regularly examine our production to ensure optimum batch size. Our ERP system both handles the batch size determination and the scheduling of the new batches to ensure that parts are produced at the right time and with the right quantity. When maintaining a Kan-Ban System for our aerospace customers it is vital that we both maintain enough inventory to handle their surges in demand, as well as minimize our batch size to allow us to produce the wide variety of parts that are requested.

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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.

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May 7th, 2010|Tags: Aerospace Machining, Lean Manufacturing, overproduction, the seven wastes|