Not as written
The wording for Thunder Gauntlets that are a part of the Armorer Alchemist's Guardian Armor model state:
Each of the armor’s gauntlets counts as a simple melee weapon while you aren’t holding anything in it and it deals 1d8 thunder damage on a hit.
The "and it deals 1d8 thunder damage" clause only applies when the gauntlets are ...
The armor attaches to you and can’t be removed against your will.
The rule is pretty black and white. However the answer is there as well. It cannot be removed against your will. Arguably some magical compulsions might or might not change your will. However, under any definition old fashioned trickery works.
Consider if there were a cursed +1 plate armor, ...
This doesn’t sound like much fun.
It sounds like this character is trying to have a bit of flavorful fun with their character’s abilities. From what I can tell, what they are doing isn’t affecting the mechanics of the game at all. It sounds like they are just trying to add some fun flavor to their character.
Why in the world would you punish this?
If you ...
The armor attaches to you and can’t be removed against your will. It also expands to cover your entire body, although you can retract or deploy the helmet as a bonus action. The armor replaces any missing limbs, functioning identically to a limb it replaces.
Arcane Armor description
That's pretty cut and dry. You cannot remove it against their will. ...
The interaction is unspecified, so a ruling is required
This is one of those cases that the rules don't account for. The text of Haste, of course, doesn't mention the Steel Defender, and the rules for the Steel Defender don't explicitly call out Haste. The DM will need to make a ruling, and there are a couple of defensible rulings I can think of:
Each use ...
You add your Intelligence Modifer, or Strength if you prefer.
The Armorer’s 3rd level Arcane Armor feature states:
Each model includes a special weapon. When you attack with that weapon, you can add your Intelligence modifier, instead of Strength or Dexterity, to the attack and damage rolls.
The thunder gauntlets are the special weapon referenced here.
Breastplate is fully compatible
I don't know whether everyone will agree with my reasoning, but I believe the Arcane Propulsion Armor infusion explicitly guarantees that gauntlets are provided. Here is the relevant text:
The wearer of this armor gains these benefits: [...] The armor includes gauntlets
My interpretation is that entirely explicitly, Arcane ...
They probably shouldn't "stack"
For the record, the text of the two abilities in question is reproduced here.
Guardian Armor comes with Thunder Gauntlets:
Thunder Gauntlets. Each of the armor's gauntlets counts as a simple melee weapon while you aren't holding anything in it, and it deals ld8 thunder damage on a hit. A creature hit by the gauntlet ...
We can definitely make gauntlets having both properties.
The 9th level Armorer Artificer feature Armor Modifications states:
You learn how to use your artificer infusions to specially modify your Arcane Armor. That armor now counts as separate items for the purposes of your Infuse Items feature: armor (the chest piece), boots, helmet, and the armor’s ...
if a creature has the ability to cast a spell at a range of touch, is there any reason why it would not have the ability to cast a spell with a range of self?
The homonculus delivers a spell you cast...
(emphasis mine). The homonculus is not a caster: it's just a delivery mechanism (like your hand) for touch spells. The caster is always "you" .....
Allowing self spells to be considered touch spells would be unbalancing.
Spell casters are already very versatile and powerful characters. The downside is often the risk of exposure to melee combat. Increasing the versatility of the self range spells and decreasing the risk to the caster would allow the character to outshine others.
Improves the uses of ...
Touch and Self are entirely separate ranges for spells
The section on "Range" states:
[...] Most spells have ranges expressed in feet. Some spells can target only a creature (including you) that you touch. Other spells, such as the shield spell, affect only you. These spells have a range of self. [...]
The ranges are entirely separate, and though ...