While there are things that give a fractionally better gain rate or ingot use, the most efficient item for "make max" for smiths above 100 are the regular and royal circlets (headgear).
They take six ingots per (and you get back 4 of the 6 if at 101.2 or higher mining with mining gloves on), and their very low weight is such that you can make as many as you can hold (under the 125 item carry max) inside a salvage bag, so you should be able to make 100+ at a time, use salvage bag, reload, and do another bagful.
The "Make Max" method requires you to look at the screen every 5 minutes or so (And be using tools with enough charges - the vet reward house add-on that can be loaded up to 5000 charges by dropping in hammers, tongs and sledgehammers are great for this).
However, the efficiency in recycling also makes them optimal for the make & recycle method that some used to use (that, requiring many more actions, actually takes longer than using make max and a recycle bag, for small objects).
