Inward Formed L-Shaped Ribbon Leads

Hello, I am new to the PCB world and currently, I oversee the inspection of our company's PCBs on our AOI machines. The directive given to me was to inspect boards according to IPC Class 2. For leads that fall under the Inward Formed L-Shaped Ribbon Leads, it shows a formula for inspecting the Minimum Fillet Height. Until a couple of weeks ago I wasn't familiar with this inspection criteria and our QA department has never inspected for this before.

I've since started programming our AOIs according to these criteria, and I've noticed that for the Tantalum Capacitors, we are only achieving a Minimum Fillet Height of around 150um to 200um. The measured H for these package types has a span of 1mm to 1.75mm. Using the formula, the lower end of the range would be 350um with the upper end being around 540um. Most of our Stencils are 4mils with some being 5mils. I've the measured lead width and pad width and everything falls within the Datasheet's tolerances.

My question is, is this a normal occurrence? Is the minimum height for the solder fillet something that is difficult to achieve? How do others go about achieving the desired result?

Thanks,

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