Use your Hammer to create the weapons of the gods, forged from the fires of your soul. These weapons work better for you and your party

Spell casting

When you reach 3rd level, you augment your martial prowess with the ability to cast spells. 

Cantrips. 
You learn two cantrips of your choice from the Wizard Spell List. You learn an additional wizard cantrip of your choice at 10th level. These must be reasonable to use with a weapon.

Spell Slots. 
The Arcane Blacksmith Spellcasting table shows how many spell slots you have to cast your spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell’s level or higher. You regain all expended spell slots when you
finish a long rest. For example, if you know the 1st-level spell shield and have a 1st-level and a 2nd-level spell slot available, you can cast shield using either slot.

Spells Known of 1st-Level and Higher. 
You know three 1st-level wizard spells of your choice, two of which you must choose from the abjuration and evocation
spells on the Wizard Spell List. The Spells Known column of the Eldritch Knight Spellcasting table shows when you learn more wizard spells of 1st level or higher. Each of these spells must be an abjuration or evocation spell of your choice, and must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one
new spell of 1st or 2nd level. The spells you learn at 8th, 14th, and 20th level can come from any school of magic.
Whenever you gain a level in this class, you can replace one of the wizard spells you know with another spell of your choice from the wizard spell list. The new spell must be of a level for which you have spell slots, and it must be an abjuration or evocation spell, unless you’re replacing the spell you gained at 8th, 14th, or 20th level.

Spellcasting Ability. 
Strength is your spellcasting ability for your wizard spells, since you Forge your spells like a Blacksmith Forging weapons. You use your Strength whenever a spell refers to your spellcasting ability. In addition, you use your Strength modifier
when setting the saving throw DC for a wizard spell you cast and when making an attack roll with one.

Spell save DC = 8 + your proficiency bonus + your Strength modifier

Spell attack modifier = your proficiency bonus + your Strength modifier

Fighter level, cantrips, spells known, spell slots

                                                                 1.     2 .     3.      4

3.                     2 .             3.                    2 .   --        --          --

4.                     2 .             4.                    3

5.                     2 .             4 .                   3

6.                     2.              4.                    3

7.                     2 .             5.                    4 .  2

8.                     2.              6.                    4.   2

9.                     2.              6.                    4 .  2

10 .                  2.              7.                   4 .   3

11.                   3.              8.                   4 .   3

12.                   3.              8.                   4.    3

13.                   3.              9.                   4.    3.   2

14.                   3 .            10.                  4.    3.    2

15.                   3 .            10 .                 4.    3 .   2

16.                   3.             11 .                 4.    3.    3

17.                   3.             11 .                 4.    3 .   3

18.                   3 .            11.                  4 .   3.    3

19.                   3.             12.                  4.    3.    3 .    1

20.                   3 .            13.                  4.    3 .   3 .    1

Forges Hammer

At 3rd Level you also get a bond with a hammer of your choice. This hammer is considered a Spell focus for you and you can call it to your hand as a bonus action while it's on the same plane as you. Further more when you Cast a spell through your Hammer you may use a smack with it to take the place of any Somatic or Material component as long as that Material Component does not cost money.
This hammer is all you need to forge gear with Blacksmiths Tools.

Sharpen the Blade, Blunt the Hammer

At 7th lvl you can begin making weapons better. As your Forging skills has grown stronger. You gain expertise in Blacksmiths tools. you may also use your Hammer to Hammer out the fine edges of blades and blunt the edges of Hammers, as a Bonus action You can Make a make a Blacksmiths tools check to increase the total damage output of weapons roll a D6 for a number of rounds equal to your Prof bonus any hits you make will do extra damage equal to what you roll. at higher levels this increases. d8 at 10th, d10 at 15th and d12 at 18th.

Magic Weapons and Armor

At 10th level you can place Magic into your weapons and armor. as a action you can cast a Spell and store it up in your blade. the spell is cast as normal but nothing happens instead it deals a extra effect dependant on the spell. if the spell deals damage it deals 2 dice lower then what the damage would be of the spell. As it takes some energy away from the spell putting it into the weapon. If you are casting a Spell on armor it's effects activate on the next time you take damage. You can only have 1 spell stored into a weapon or armor at a time and it goes off when the conditions for it to go off are met. otherwise it can remain in it for ever.

Improved Magic Weapons and Armor

At Level 15 you can start to make the spells better. As you do so you can enchant already magic gear as long as the magic enchantments would not compete with each other. For a +1 weapon, you can place 1 spell, a +2 can have 2 spells, and a +3 can have 3 spells. You can have them all go off at once or choose when they go off. Armor is the Same way.

Master of the Craft

At Level 18 you are a master of your Craft. Whenever you make a weapon that is forged with your Hammer to make it better in some way, be it sharper, blunter, or enspelled, you can choose to make that Effect Permanent with a hour ritual. However you may only have 1 of each effect active at a time. you may only Sharpen your blade or Blunt your hammer and enspell it with one spell this way. However it becomes your Masterpiece it is a +3 weapon and can use the spell in it whenever it hits a target.