We manufacture large feeder mixers for feeding cattle in our shop. In the design process we will use the overall shell as a reference part to assemble many subassembly components to. As we now have been requested to include the weight of our assemblies I am attempting to figure out how to exclude the reference items from the assembly weight. A quick and easy way to do that is to use envelopes but that has it's own set of things to work around. I have seen reference to setting the weight of the reference items to 0 at the assembly level but have not been able to figure out how that is done. We have a custom property called weight set to be equal to the mass. In the reference item I have created a configuration and set both the mass and weight to 0 for the configuration but that does not work. My google fu is not strong today, can someone point me to who to set the subassembly weight at the assembly level so it doesn't mess with the actual sub weight?