Originally Posted by rvbuilder2002
The main concern is in situations where the plans call out the use of washers as spacers......
Even though both washer designations are aircraft grade hardware, the NAS part has a much tighter tolerance for thickness than the AN washers have.
This causes a lot of problems when calling out a specific # of washers for an assembly that they are used as spacers in.
So in instances where you are just using a washer for the common purpose of load distribution and abrasion protection AN960's are fine, but NAS should be used when it looks like a specified stack-up is dimensionally sensitive.
I'm trying to cross reference the 5702-75-060 and 5702-95-30 washers and it appears this may be a Vans part number. Is there a better part number to cross reference? I have a big order going to Spruce for other stuff and wanted to include those. It calls for them on the RV-4 blueprints on drawing 28.