Forging the Iron Blade and Unfinished Blade
Start With the Iron Blade
The Iron Blade is an early smithing_transform result. To produce it you need the correct base item and addition item placed into a smithing setup. The Iron Blade is the foundation for the Unfinished Blade, so make at least one before moving on.
Turning the Iron Blade Into an Unfinished Blade
The Unfinished Blade is also produced through smithing_transform. Feed the Iron Blade plus the required addition into the smithing process to convert it. The Unfinished Blade is not a finished weapon; it is an intermediate step toward the Spirit Sakura Steel line.
If you are unsure which addition item is required, check the smithing_transform recipes available in your recipe book or JEI-style viewer. The mod contains five smithing_transform recipes total, and the Iron Blade and Unfinished Blade are two of the outputs among them.
Keep spare Iron Blades on hand. Because the Unfinished Blade consumes one Iron Blade per conversion, batch-crafting Iron Blades first saves trips to the smithing station. Store finished Unfinished Blades separately from raw Iron Blades so you do not accidentally feed the wrong item into the next step.