In a mixed model production line, different products may have different work content at different stations. Hence, some stations may need a longer or shorter time depending on the product. This requires careful planning of the assembly line. If this is not taken into account, it may cause significant idle time with all stations along the line. This is the first of a (very) long series of posts looking at Mixed Model Sequencing (i.e., the behavior of unbalanced workloads, and different ways to address these issues).
Logistic
Maintaining Weak FIFO in Parallel FIFO Lanes
Sometimes you would like to put more material in a single FIFO lane than the space you have available. In this case you would have to use a combination of two or more parallel FIFO lanes. In my last post I described how to maintain a strict FIFO sequence in parallel lanes. This post looks at an easier but less accurate method.
Point-of-Use Provider Routing

This is my last post of a series of three posts on point-of-use providers (also known as mizusumashi, water strider, or water spider). In this post I will go into much more detail on the routing of the point-of-use provider. A less-busy point-of-use provider can handle multiple lines. Similarly, very busy lines may have multiple point-of-use providers. Here I will show you some more details on these possibilities.
Point-of-Use Provider Calculations
In this second post of my series on point-of-use providers (also known as Mizusumashi, water strider, or water spider), I will discuss the calculation of the workload for the point-of-use provider … although calculation is a way-too-big word for what is, in practice, guesswork with limited data of low quality. However, I hope it helps you with planning your point-of-use providers.
Introduction to Point-of-Use Providers (or Mizusumashi)
The point-of-use provider, also known as Mizusumashi, water strider, or water spider, is a worker that supplies material to the point of use. Similar to a waiter bringing food and drinks (and beer 🙂 ) to the customer, the point-of-use provider brings material to the workers. The latter, however, merely refills materials rather than custom orders. This point-of-use provider fulfills an important role between the inventory and the final point of use. Let me give you the details:
A Good Standard Needs No Explanation
Standards are one of the backbones of lean manufacturing. For a standard to be good and used consistently, it should be self-explanatory. Additionally, you should understand it well enough to easily recognize deviations from the standard. I would like to give you an example of how my thought process works when exploring a standard.
External Milk Runs
Frequently Asked Questions for Milk Runs
After discussing a lot about the milk run, its use, and its calculations, here is a post on a number of remaining frequently asked questions. Many of them are pitfalls, where it is easy to make a quick wrong guess (e.g., two milk runs on the same route will not halve your inventory at the assembly locations). Let’s get into more details.