With the printing of Thopter Spy Network and a whole bunch of good new artifact creatures, I think an Affinity-like deck with 4 Thopter Spy Network is pretty viable in Standard right now:
Have you considered Chief Engineer for your list to be able to convoke artifacts out instead of only relying on renowned weaponsmith?
Additionally, a good potential addition to this deck would be tomb of the spirit dragon. Since you are going to have a lot of colorless artifacts, being able to pay 2 mana to gain a bunch of life seems to be a decent idea for this deck - though I don't think I would run more than about 2-3 of them in the list to start, though that might go up pending testing.
The next one that I would run is ensoul artifact. You are getting a plethora of artifacts that you could put it on, and buffing a 1/1 or 0/2 thopter into a 5/5 is just straight value, and then they can join the ramrollers and juggernaughts in beatdown town.
The last one that I have been enjoying is running 2 copies of War Horn, to give all your attackers +1/0 - it makes your thopters that much scarier on the attack, and it is another thing to help you keep artifacts out for the spy network.
From what I've tested the Weaponsmith is actually rather slow and doesn't help fuel much the deck, it doesn't have that many high costing artifacts to truly be worth it, as you won't get much use of having mana-creatures just to cast cards that don't cost that much anyways.
4 Darksteel Citadel
2 Foundry of the Consuls
4 Ornithopter
4 Renowned Weaponsmith
4 Bonded Construct
3 Phyrexian Revoker
2 Hangarback Walker
4 Juggernaut
4 Ramroller
4 Chief of the Foundry
4 Ghostfire Blade
1 Heart-Piercer Bow
4 Thopter Spy Network
Renowned Weaponsmith is like a Llanowar Elves on steroids in this deck.
Thopter Spy Network is an amazing card that pumps out creatures and draws cards for you.
Ramroller and Juggernaut are just undercosted beaters that get better with all of the synergies in here.
C Long Live Eldrazi C
Additionally, a good potential addition to this deck would be tomb of the spirit dragon. Since you are going to have a lot of colorless artifacts, being able to pay 2 mana to gain a bunch of life seems to be a decent idea for this deck - though I don't think I would run more than about 2-3 of them in the list to start, though that might go up pending testing.
The next one that I would run is ensoul artifact. You are getting a plethora of artifacts that you could put it on, and buffing a 1/1 or 0/2 thopter into a 5/5 is just straight value, and then they can join the ramrollers and juggernaughts in beatdown town.
The last one that I have been enjoying is running 2 copies of War Horn, to give all your attackers +1/0 - it makes your thopters that much scarier on the attack, and it is another thing to help you keep artifacts out for the spy network.