Using The 4-step Method When There Is Variation
We recently received the following question. I have started a pilot of TWI- Job Instruction at one of our facilities. I don't recall reviewing how to instruct using the 4-step method when there is variation. What I have is a JIT assembly line that builds driver control modules for various suppliers. Our line builds match the supplier build, so the assemblies vary from one to another. For example, the assembly in the station is for a hydraulic braking system and the next 3 assemblies entering that same station may be for a pneumatic braking system, and within those 3 pneumatic assemblies, there may be 2 different configurations. Since this is an assembly line, the necessary tools to complete the assembly can't easily be taken to a controlled environment and taught. Do you have any insight or advice on how to handle training to the 4-step method without completely disrupting production? Will it fall under the same category as a long operation were the instructor does 1 type of system and configuration at a time until the operator has learned? If that is the case, how do we handle it when types and configurations are rare or sporadic? Senior Master Trainer Patrick Graupp responded: Thanks for your question and it sounds like you’re really in the thick of things with your JI training. Keep up the great work! Your question is quite relevant because good instruction using JI is the critical factor here if you want to keep up with the high demands of JIT and other Lean initiatives just as you have described. It’s what will keep your company competitive. You answered your own question when you sensed that this is the same kind of problem as instructing a long operation, where you have to teach it one element or unit at a time. Remember, we should never give the learner “more information than they can handle at one time” so teaching them one job at a time is the way to go. In order to teach at the line, you will have to have an experienced operator at the station who can handle the different variations that come down the line, even as you teach the new operator these tasks one by one. Teach the most common operation first since they will have ample opportunity to practice; the veteran can deal with the other jobs that come down the line at the same time. When you teach the operator the most common task, all the other variations are just that, “variations” on this basic task. So pick the most basic jobs to teach first and build on those skills. Once the new person has learned the most common operation, you can begin teaching the variations one by one and this part of the learning will be much faster because they have learned the basics. Once the new operator starts to handle a larger share of the assemblies coming down the line, the veteran operator can move on to other tasks in the area coming back to the station only for those “rare or sporadic” pieces when they show up. Eventually, the new operator will be able to take over all the tasks. Think about it—we cannot learn “everything” all at once. But if we have an intensive instruction method like JI, we can compress this learning time without sacrificing quality and productivity. But there has to be a transition period for the new person to get up the learning curve. They cannot just jump into a line and do it all at once. The “sink or swim” approach is not acceptable and invites disaster.