"It depends"

Late medieval and renaissance armour saw a lot of variation in both material and thickness. On one hand you have everything from basic iron up to hardened steel (and varying amounts of slag inclusions on top of that), and on the other hand the thickness often varied a lot within a single armour to maximise protection where it was the most needed while keeping the weight down (especially where that was the most needed), so your finger lames won't be as thick as your breastplate, and said breastplate will likely be thicker in the middle than on the sides. And of course just how thick they made the breastplate could vary immensely, going from "not that thick" in the middle of the 15th century to "anything from not that thick to immensely bloody thick" 150 years later.

Alan Williams made a decent attempt at starting to out all of that together into some manner of quantitative analysis in the latter chapters of The Knight and The Blast Furnace: https://www.mediafire.com/file/2lw9w2stunb6zyt/The_Knight_and_the_Blast_Furnace.pdf/file