I'm designing something and part of it has a aluminum block that will be have a M6 threaded hole. I want to add a nylon washer to give it a stop nut or lock nut type of feature. I'm looking for input into the appropriate diameter and dimensions of the washer. also I'm wondering if there are any special considerations for the housing of that washer or would I just simple create a housing/cutout that would fit the washer? Nylon/POM type? Thanks for any insight.