304 Stainless steel is probably the easiest metal there is to spot weld. Here's a link to a basic spot welding manual in pdf form. There's useful information about the proper welding tip shape and size to use for various material thicknesses. Also time and pressure. You will need to water cool your welding tips due to the quantity of pieces you are welding.
https://seedorffacme.com/wp-content/...-FO-Manual.pdf