Kanban Rule #6

Kanban Rule #6: The number of Kanbans is reduced carefully to lower inventories and to reveal problems.

Applying this rule in your studio: in a studio where sales levels are consistent, then reducing the number of kanbans is one way to reduce inventory levels, which improves cash flow and increases production speed. However, in a studio where sales levels are growing (and often growing quickly!), then it’s more common to add kanbans than to take them away. Reducing kanbans is recommended for when sales level off at your studio or if you’re working to reduce the total inventory you have on hand (see Chapter 12).

Kanban Rule #5

Kanban Rule #5: Defects and incorrect amounts are never sent to the next downstream process.

Applying this rule in your studio: if there is a problem, it gets stopped immediately! Never send a product with a problem further down the process where it could possibly end up in the hands of your customer. If defective products stay in the kanban, your next process won’t have the right number of correct items. Defective problems should get flagged immediately and removed from the production floor and dealt with totally separate from regular production.

Kanban Rule #4

Kanban Rule #4: A Kanban should accompany each item, every time.

Applying this rule in your studio: you shouldn’t be making product unless your system needs it, shown by having an empty kanban. The labels help make sure each product is labeled.

Kanban Rule #3

Kanban Rule #3. No items are made or moved without a Kanban.

Applying this rule in your studio: kanban is your autopilot! Use it instead of a production schedule, to tell you how much and what products to make.

Kanban Rule #2

Kanban Rule #2. Supplier (upstream) produces items in the precise amounts and sequences specified by the Kanban.

Applying this rule in your studio: make product in the same size and quantity each time. When filling a kanban, don’t overfill it or fill it partway. The number of items per kanban, and the number of kanban, is how the total amount of product is controlled.

Kanban Rule #1

Kanban Rule #1: Customer (downstream) processes withdraw items in the precise amounts specified by the Kanban.

Applying this rule in your studio: when you take a full kanban of product, you can always know that exactly how many products are included because they’re always the size/quantity indicated. If the bin or kanban is full, there is no need to count or measure how many items are included.

Toyota’s Six Rules for Effective Kanban Systems

The basic rules of using kanban are the same whether you are running a car factory or a jewelry studio. These rules were developed at Toyota but can be applied at your studio.

1.      Customer (downstream) processes withdraw items in the precise amounts specified by the Kanban.

2.     Supplier (upstream) produces items in the precise amounts and sequences specified by the Kanban.

3.     No items are made or moved without a Kanban.

4.     A Kanban should accompany each item, every time.

5.     Defects and incorrect amounts are never sent to the next downstream process.

6.     The number of Kanbans is reduced carefully to lower inventories and to reveal problems.

What Should You Make Today?

How do you decide what product to make on any given day in the studio? With limited time, making the wrong thing hurts twice. You don’t want to make product that isn’t selling, and you don’t have time to waste when you have orders to get out the door. By using this system, your to-do list is entirely out of your hands and controlled by your customer. There’s no need to calculate what needs to be made, you simply visit the area where empty kanbans are kept and see what needs replenishment. All the time spent on ‘production scheduling’ can now be used for more practical things, like production itself. Manual changes to production are reduced to non-kanban orders such as custom products and seasonal items. Using this system is also useful when employees are being onboarded, as it’s obvious what needs to be made next.

Information to include on your kanban

Since your kanban is the indication you need to make more product, you should include information on the tray to tell the team what needs to be made. The product name and quantity per kanban is typical, as is the storage location where the kanban should travel to once it has been filled, and where to return it when empty.

Card, bin, tray, hopper?

Kanban: translation is “visual card”. A written card can accompany any size item; if items are small enough to fit into a bin or tray of some kind, it’s best to place the card on the outside of this bin by labeling the bin. You can call this whatever makes sense in your own studio. At Meliora they are called “trays” because the most often used size is a re-purposed cardboard fruit tray collected from a local wholesale store.