Sorry meant to say you can keep the jar at 1.

Something to consider, the Cranial Plating 's ability with the two black mana can be used at instant speed to f*ck with your opponent. Let me paint you a picture: you've got ornithopter, Etched champion, steel overseer, and some other noncreature artifacts in play, including the plating on your very beefy champion. Unfortunately, your 'thopter hasn't yet benefited from the overseer, as you just cast it last turn. Then your foe swings with some nice, powerful critter and you block it with your pitiful 0/2. Then you wipe the smug grin off that d!ckbag's face when you tap BB to switch the plating over to the thopter, killing his precious critter. That'll give the b@stard some pause for thought.

If the blue mana is only for the two Master of Etherium , maybe drop them and add black mana for the Cranial Plating , or do red for Shrapnel Blast or Galvanic Blast ?

Although Master of Etherium probably gets quite large in a deck like this

I'd drop Arcbound Ravager , Indomitable Archangel , Batterskull (good card, but doesn't make a ton of sense in here), Ichor Wellspring , Staff of Nin . None of these cards fit your theme, and some of them are just bad.

Add in 4x Ensoul Artifact . This is a good card and can turn any of your 12 0 drops into a 5/5 creature. Darksteel Citadel can turn it into a 5/5 indestructible creature that can swing on turn 2. Thoughtcast is pretty much necessary as well. Great card.

I'd run it more like this:

Creatures: 20 - 4x Etched Champion , 4x Memnite , 4x Ornithopter , 4x Signal Pest , 4x Steel Overseer

Artifact / Enchantment: 12 - 4x Cranial Plating , 4x Mox Opal , 4x Ensoul Artifact

Instant / Sorcery: 8 - 4x Dispatch , 4x Thoughtcast

Land: 20 - 4x Darksteel Citadel , 4x Glacial Fortress , 4x Hallowed Fountain , 6x Island , 2x Plains

This will give you a much faster curve and a much more consistent deck.

Ummm you are mistaken on so many levels if you want to suggest removing Arcbound Ravager . Actually Ensoul Artifact wouldn't work on a Darksteel Citadel to swing on turn 2 unless you had a springleaf drum and Memnite or Ornithopter out already. Which is a possibility but not guaranteed.

Saljen and everyone else, thankyou for all the help... I will slowly make the changes in next few days. However I thought Ichor Wellspring is good. Increases metalcraft Cranial Plating and also I thin my deck and gain a card.... same with Staff of Nin card advantage is great. Why are they so bad??

Well Staff of Nin is bad because an artifact deck should be done winning before it is dropped. Or worst case be in a bad losing position because of blowing out all the cards in your hand, and then the opponent stabilizes somehow also before dropping staff of nin. You don't want a hand with the staff in hand wishing you had even a Thoughtcast instead, or even a cranial plating. Ensoul Artifact would just be better to have than that staff too or any of the other artifact creatures. A lot of the times you will sac remaining artifacts such as Darksteel Citadel just to push the damage through for lethal to the opponent to your Arcbound Ravager . Or if you have a Cranial Plating out you just want to drop every cheap artifact that exists then draw more with thoughtcast and also play those. The really efficient speed affinity decks run Galvanic Blast as a finisher. Lastly you would probably run some number of Inkmoth Nexus and at least a playset of Blinkmoth Nexus to activate to buff cranial further. Also a cranial plating on an inkmoth nexus could easily be a 1 shot or damn near it.

Awesome cheers

You can drop down to 22 lands.

Also why do you have black mana sources?

I would drop 4x Godless Shrine for 4x Springleaf Drum . The drum let's you play a turn like this: Darksteel Citadel , Ornithopter /Memnite , Springleaf Drum , into Signal Pest or another overpowered 1-drop or even Frogmite . I don't even run Mox Opal in my deck and I have no mana troubles. +1 for Metalcraft! (favorite mechanic)

my humble thoughts:

20 lands will definitely work so i'd drop 1 of Isolated Chapel , Godless Shrine , and Watery Grave ..then i'd sideboard Indomitable Archangel , Thoughtcast , and Welding Jar to drop you down to 60 total..also, i'd definitely try to sideboard Galvanic Blast because 4dmg for 1 mana is oh so sweet (and mox opal takes care of that red mana naturally of course)

nice build +1

(shameless plug for my Infection for Affinity deck)

black mana is for Cranial Plating instant swap! which is cool with Inkmoth Nexus and also for any unblocked creatures for a win swing

It still definitely needs 4 Arcbound Ravager and you could potentially cut a memnite down to 3. Etched Champion could be a 3 in the main and 1 in the side. The biggest players are ravager, with Steel Overseer out especially so. Or just anything with a cranial on it.Maybe you don't need 4 dispatch in the main as much as you think, although it is nice. You will have so much power on the board creatures can be removed that way too, or just ignored. If you are really dead-set on dispatch you could replace it with galvanic blast 4 main. Then you would swap the white sources for red. At that point need to also drop the Indomitable Archangel (because at this point you do not want to need white anymore), for Galvanic Blast . Do not underestimate that red card, every burn deck runs Lightning Bolt and in this deck that card is even better than that. It will remove most everything in modern (likely without even using metalcraft) and have the potential just to end the game instead of removing a threat. Springleaf Drum should be in the main and maybe go down even more to 18-19 lands. With Mox Opal and the drum your mana should be fine. This allows your sideboard to basically splash into any color, however this deck cannot afford to side out much either. I guess I should submit my deck idea since I actually base my opinions around an affinity deck I own, but have minimal experience with it. I have been playing american control for so long in modern. I have been slowly getting the mox opals, lands, and creatures to build it and am pretty satisfied with my version.

so people are voting Galvanic Blast over Dispatch and Indomitable Archangel ??

are you trying to make it an affinity deck or not? if so you need to drop all the pain lands and add 4x Inkmoth Nexus 2x Blinkmoth Nexus 4x Glimmervoid

Check my link for a top tier competitive affinity list, not sure if this will help or if you have already seen them.

http://mtgtop8.com/event?e=8208&f=MO

Your highest CMC is 3, and you don't have many of those. Sure you got a 5 drop, but you will never cast it for 5 (I hope).

Your Mox Opals are essentially lands all the time.

So what I'm saying is that you can probably cut some lands to get closer to 60. I wouldn't cut 5 lands, but that's a start.

I suggest going to http://www.mtggoldfish.com/archetype/8972#online it's the deck your looking for with different tweaks to them.

Genesis Chamber with Inkmoth Nexus and Blinkmoth Nexus is always a good combo.