Tools needed for AR lower build?

[HALLAUSTIN]

What tools are needed for building an AR lower, assuming that you have all the parts?

 

[JesusQueen]

I used vice grips, needle nose pliers, an allen key for the grip, roll pin punches, and a small brass hammer

 

[Mobuck]

The plastic fixture that mounts into the magwell and holds the lower in a vice is a very handy gadget. I also have the detent installation tool from Brownells, proper sized punches, a couple of nonmarring hammers, and a block of lead alloy as a backer when driving pins. It can be extremely frustrating when you launch the takedown/pivot pin detent during assembly and have to wait while the replacement is shipped(once launched, the possibility of finding the detent is about 0.1%). Not properly supporting the "ears" that hold the triggerguard rollpin will almost certainly result in breaking one while driving the pin through and I found the lead block a cheap alternative to the polymer benchblock.
I assembled 2 or 3 just using a pad on a table but the magwell device is a big step in convenience and prevents dings. It also works for holding the rifle for cleaning, scope/sight installation, and stock work.

 

[Ridge_Runner_5]

I did my last lower build with just a pair of vice grips wrapped in electrical tape and a flathead screwdriver.

 

[Fishbed77]

I've found a standard c-clamp (with some electrical tape to prevnet marring)to be a very useful tool to intall the trigger guard and bolt release pins.

Instead of whacking with a hammer, you can slowly and carefully press the pins in to prevent scratches or bending of the trigger guard "ears."