I am lvl 55 smithing and have trained by making iron daggers, it seems to be pretty slow now. Is there a better way to train smithing i want to to go all the way to 90?

Make jewelry. The higher the value of the item, the more xp gained.

Also, I believe the Warrior Stone helps as does being well rested. You'll gain additional xp for each. It may also help, as has been suggested here many times, to obtain the Transmute spell and turn iron ore to gold for jewelry making.

If you have Hearthfire, making nails and other iron building materials really seems to help.

A few patches ago, they fixed Smithing so now it's the value of the item that determines how much you gain in level.

So, Daggers slow, Jewelry and complicated weapons/armor faster leveling.

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