Recraft concentration should be free once you have crafted for first time! It is so much waste to burn concentration and I choose not help random people due to it cost concentration, it is just wrong!
It’ll solve itself with time, you can craft enchanted gildeds without concentration on an item whose wheel you’ve developped until about 15-20 (assuming you have all the rings that lead into that ring as well as the flat skill up rings from other trees). I’ve crafted my 675 weapon without any concentration on 5 star and will likely not need any concentration to do the same to my shield in a weeks time.
Are you using those skill up items you sometimes get? +5/10/20 skill on the craft can absolutely help you push the last bit of missing skill or atleast shave some cost off of the concentration.
Inqenuity 21 %
If you use +skill then it will cost more concentration so no it is not possible to craft any item with no concentration.
The intent of Concentration is to limit the amount of max-quality crafted items, because otherwise bot farms and AH goblins would have a grand monopoly on those, as has happened in the past.