Because the former is good for all-out melee but the latter is intended for range and stealth, I was exploring the idea of using different base armors for each of these: heavy armor for Guardian (maximum AC of 18, disadvantage on stealth – i.e. plate armor), and medium or light for Infiltrator (maximum AC of 16 or 17 when not accepting disadvantage on stealth – i.e. breastplate or studded leather armor).
An Armorer can't have two sets of Arcane Armor active simultaneously, so I needed to figure out what it would take to change from one to the other.
According to the Arcane Armor feature (TCoE, pg. 15-16):
[...] As an action, you can turn a suit of armor you are wearing into Arcane Armor, provided you have smith's tools in hand.
You gain the following benefits while wearing this armor:
- You can [...] doff the armor as an action.
Furthermore, the table on page 146 of the Player's Handbook indicates how long it takes to don normal armor:
- Light armor: don in 1 minute
- Medium armor: don in 5 minutes
- Heavy armor: don in 10 minutes
So changing out of heavy Arcane Armor and into medium Arcane Armor would take: 1 action (doff heavy Arcane Armor) + 5 minutes (don normal medium armor) + 1 action (convert normal medium armor to Arcane Armor) = 5.2 minutes. In general:
Swapping any normal armor in for existing Arcane Armor takes 2 actions plus the time needed to don the normal armor.
This struck me, because it seemed to be a shortcut for swapping between Armor Models. Normally, the Armor Model feature specifies that you can do so when you finish a rest (TCoE, pg. 16):
You can change the model whenever you finish a short or long rest, provided you have smith's tools in hand.
Yet it seems like having a second set of normal armor available (of any class) allows you to change models in either 1.2, 5.2, or 10.2 minutes, instead of the 1 hour required by a short rest.
Now, because an artificer can only activate infusions after a long rest, any infusions on the former Arcane Armor must stay with it until at least the end of the next long rest, but this sacrifice might be worth it if you're in a dreadful rush and you really want the model you don't currently have. And you might even have one infusion "pre-loaded" in armor you'd set aside to be swapped in.
Is my logic sound? Or have I missed something that would disallow this shortcut?