Hello Instinctive!
This subject is little bit complex ...,maybe ando or tevas can give more info on this ....but here I go...
It is true that LUC stat does increase your chance for enchantment and it is best if it is very high (that means luc dyes +5, accessories (rabbit, hats etc+3 luc-old ones from a time ...long forgotten +food---from fish --also from long time +1 luck, maph potion ,max exalted quest +cloak, dimensional bracelet luc, max artifacts (just put the stones no enchant required-do not spend adena here remember you just want LUC -...fill the slots) emrald (greater max) , enchanted +++armor (of course) + luc buff from aden (npc 7 mil adena) ....and so overall -luc on all your gear max were luc appears....
Ok ...so now for sure you will have much more than +70 (a lot more) if you have a dwarf of course ---BUT what kind of dwarf you need?
Answer - a dwarf spoiler -because ---GREATER luc -stat that he gets- best of all classes (still)
BUT still is not enough....
After you have all that (or max as much as you can let us say 85 luc) then buy Maphr's Shirt and make it +10 ( this is old info , should be more info here in the forum about special shirts ). A here it is:
Magic shirt filled with the power of Maphr, the goddess of earth.
Can be enchanted to +10 using Elemental Shirt Enchant Scrolls. When enchanted to +7 or higher, the enchant success rate is increased.
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After you have all that try again using this royal tickets for enchant and you will actually see some results.
I hope this small message helped you in some way good luck!