For a table describing the main workshop see Products.
Blueprints can be upgraded with crafting lore. Each upgrade increases the revenue by 10 percent. Keep in mind that the revenue does not grow exponentially. So if you upgrade a blueprint to level 11, the revenue is doubled. If you upgrade a blueprint to level 21, the revenue is tripled.
Merging two blueprints keeps the current income (summed between the two blueprints) and resets the upgrade cost.
This has a net effect on revenue as taking their combined upgrade levels, adding them together, and increased by 10.
For example, if you have a Leather Blueprint I lv5 ($1260) and a Leather Blueprint I lv2 ($990). Merging them will result in a Leather Blueprint II lv1 ($2250). Upgrading this new blueprint will give 10% of its base value as an increase (in this case, each additional upgrade increases revenue by $225). Thus the higher the original blueprints level before merging, the more cost-effective upgrades will be after merging.
Ideally you'll want both blueprints to be about the same upgrade level before merging. For example, the initial revenue of wood is $1. On level 21 the revenue is $3. Merging two level 21 blueprints will result in a level 1 blueprint and the upgrade costs will be reset and the revenue will be $6. If you update this blueprint to level 21 the revenue will be $18, which is 18 times as high as the initial revenue.
Splitting a merged blueprints costs 50 gems. You can split a Stage III into two Stage IIs, or a Stage II into two Stage Is.
The two output blueprints will retain some upgrade value, although a lot of spent lore will be lost. The output blueprints will be identical with a number of upgrades neccessary to have half the score of the base (unupgraded) original blueprint.
e.g. A Stage III blueprint with a base score of 1000, upgraded to 2000, when split, will always result in two Stage II blueprints with scores of 500 each.
In the event that the base score is odd, the game will round down.
A player merged a Rawhide I Blueprint (upgrade level: 22) and a Rawhide I Blueprint (upgrade level: 4). This results in a Rawhide II Blueprint (upgrade level: 1). If the player splits the Blueprint he will get a Rawhide I Blueprint (upgrade level: 13) and another Rawhide I Blueprint (upgrade level: 13).
A player merged a Wood I Blueprint (upgrade level: 23) and a Wood I Blueprint (upgrade level: 14). This results in a Wood II Blueprint (upgrade level: 1). If the player splits the Blueprint he will get a Wood I Blueprint (upgrade level: 18) and another Wood I Blueprint (upgrade level: 18).
The evolution stage is shown in roman numerals. Two blueprints can only be merged when the evolution stage is the same. If a player has got at least two blueprints of the same product and stage it will be shown in green color. Merging two blueprints will result in a blueprint at which the evolution stage is increased by one.
See Blueprint Score
To view the math in detail, have a look at this spreadsheet .
For example, Magnificent Hilts have a base upgrade cost of 71. Internally this value is calculated as (log10(intial build price)+9) * 1.08. Plugging in the Magnificent Hilt's build price of 400e54, we get a value of 70.85. However this is the first upgrade and we want the zeroth, so we divide by 1.08 (65.6), round it (66) and then multiply by the current LPP value (e.g. 38) and arrive at the blueprint sell value of 2508.
You can sell the only copy of a blueprint that you get for free by building your first product in the workshop. However you will not get a replacement if you build that product again.