Measurement System Analysis - Nested Gage R&R
11 Replies
Measurement System Analysis - Nested Gage R&R
Recently hit road blocks in trying to complete an MSA for a Instron, peel testing device. The % Tolerance and distinct number category is not being met (<30% Tolerance, and > 5 categories). I've attempted multiple runs, carefully choosing samples, and still the variation is too large. I can't even get the parts to be distinct, no matter how much I change the seal temp, pressure, and time between parts. The parts are simply not distinct from each other. In addition, within the same parts, the repeatability is high enough that %Tolerance fails. I can't definitively say that the equipment is at fault, or the process simply can't make seals consistently.
So.....I've been thinking. The purpose of MSA's are to determine the inherent variability in the measuring process caused by the equipment and/or operator. The actual capability of the machine producing the samples doesn't matter. Why do I have to use samples from the production floor? Why can't I create my own to make sure that each part have different peel strength, so that the distinct category will be met. For example, why can't I simply use 5 different types of glue, and seal tyvek strips to a poly-film to create my own samples. Are there vendors that sell test samples to qualify peel testing equipment?
Thoughts?
So.....I've been thinking. The purpose of MSA's are to determine the inherent variability in the measuring process caused by the equipment and/or operator. The actual capability of the machine producing the samples doesn't matter. Why do I have to use samples from the production floor? Why can't I create my own to make sure that each part have different peel strength, so that the distinct category will be met. For example, why can't I simply use 5 different types of glue, and seal tyvek strips to a poly-film to create my own samples. Are there vendors that sell test samples to qualify peel testing equipment?
Thoughts?