is it possible to upgrade from large scale with the mystic forge?
Yes it is possible to transmute large scales into armored scales. You would need a total of 50 Large Scales, 5 of the tier 6 Dust (forgot the exact name), 5 Philosopher Stones and 1 Armored scale. Then combine them all in the mystic forge. This will generate a random number of Armored Scales. I use this to transmute Potent Bloods into Powerful and it usually gives me a number around 10-15. Not sure what determines the amount you get though. But you could use this recipe for most of the fine crafting materials and also ores, cloths and etc.
Terrible advice..
I just did this and got 5 scales. Nobody listen to this person.
Only lost about 10s in the end, but still kittening annoying.
I didn’t have any issues with this method. I turned 100 Large Scales into 21 Armored Scales in two conversions.