Most design engineers who want to perform mechanical simulations will need to deal with assemblies. Most products are made up from multiple parts or assemblies. How you deal with assemblies or the connection between parts in your simulation model can have a huge impact on the results. There are probably as many methods of handling assemblies as there are engineers performing simulations on them. There is no one overall governing method. Each case is different and there is no one correct method for each case. Your goal should be to pick a method which is conservative your case. The following are tips and tricks used by many analysts in dealing with different types of assemblies and connections.