Yesterday I learned a valuable lesson about making welds that do not require grinding. in the future I'll focus intently on producing welds that do not require cleanup.
The joinery is done with a 1/2" straight cut router bit on my Harbor Freight router. The mecahnical fit was great and all was square but I trashed the project because of poor welds and further weakening the base material through grinding. These joints have potential but need a better weldor to make it happen. Next time, when I get over wasting materials.
Here's what the prototype/first good effort produced. Yes, there's a conspicuous absence of close-up weld pictures.