going to be honest with you. Attunement is.... Shit.
No really. it is. People seem to think its
Something, but it really isn't.
lets go through this.
First off:
page 121
ADEPTS AND RITUALS
There are various rituals available to the adept, where
the adept’s relevant skill or attribute fulfills the role of
ritual spellcasting (steps 4 and 5). Examples: Animal
Handling for Attune Animal and Imbue; Armorer, Artisan,
or Automotive Mechanic for Imbue Item. The
gamemaster has final say on what skill the adept can
use in substitution of Ritual Spellcasting.
So at least the adept doesn't actually need Ritual Spellcasting to use a Ritual... yay <sigh>.
The adept needs the ritual "Attune item" - which is an adept ONLY Ritual. (see the red side bar pg 122 SG) Which is a kick in the nuts for a separate reason. (later on)
The First step is to "familiarize" the adept witht he object in question... and is a pretty in-depth thing... much more then just "its made of metal, and I hit shit with it"... it involves an extended test.
page 124
This involves an appropriate Logic +Technical skill [Mental] (12, 1 week) Extended Test.
In your case, that would be armorer... depending on your mental limit, this should take 2 to 3 weeks to do. Of Course, the adept could also just make himself a set of Knuckles using the B/R rules. And this would also count for this step. Also note that this does NOT cost karma...
ONCE the adept has completed the "Familiarize" step, he now has to "bond" the item..
The adept can use a technical skill for this test (armorer) and at a minimum force equal to the O.R of the item. (for Knuckles, this is going to be 6 - Manufactured Low-Tech Objects and Materials page 295 CRB)
The Ritual takes (Force) hours to complete (so, for your Knuckles, 6 hours.
After the Ritual completes the Adept must spend Karma as per the Attuned Item Table (sg 124), so in your case 6 -(
Modern crafted or mechanical items), UNLESS you decided to craft your own, in which case it would be 5. ( Simple non-mechanical or
handcrafted items).
Done.
That's it.
And what do you get for that? Possibly nothing. There is a single line inn all that muck that offers a hint of what you get...
SG 124
The skill used with the item
must be an active skill relating to a physical attribute. The
attuned item’s limit increase can stack with the adept’s
Enhanced Accuracy power.
what that bonus is, how big it is, or how you determine it, I couldn't find (so I can't help you there)...
AND, you get a whole bunch of caveats:
SG 124
Attunement provides no bonus when the item is controlled
through an electronic interface (digital, VR, AR, or
DNI), nor does it work on the complex magical auras of
foci, prepared vessels, or enchanted items. Attunement
provides no bonus to Active Magical skills
So... you can't attune a Foci....
Foci and Attuned items are separate but similar,
You Can't use an Attuned Item in AR/VR/wireless/digitally
You can't use attuned on a Vessel,
You can't attune enchanted items..
Doesn't stack to active magical skills.
So what CAN you do?
well, with yet ANOTHER Ritual (and Karma) , you can add any of the nifty things on page 132 of SG (the all red page)! Of course that isn't eveything... and GM are encouraged to come up with positive and NEGATIVE traits that can be gained and added... but yea... that's it..
So, why WOULD an adept go down this route when its not really a weapon foci, and a Weapon foci would be much more useful?.
Now normally with Ritual Magic, you can get a group of adepts and mages together to help complete the Ritual, with everyone adding to the dice pool....
BUT, Attunement is a Adept Ritual, so it can ONLY be done by the Artisan... No one else can help (this is the kick in the nuts I mentioned earlier)