A few months back I posted about adding an outdoor outlet from my garage.

When the weather finally breaks, I plan on cleaning out the whole garage, adding shelves, putting down fresh epoxy paint on the floor etc

In addition I'd like to add some additional lighting and outlets. I want to put 3-4 flourescent flush mounted fixtures on the ceiling running conduit between them to feed them off the existing switched circuit.

For the outlets those will also be surface mount with conduit (since the wall is cinder block) on a dedicated 20A circuit. Any time I install a metal box, I always ground the box to the earth ground and then ground the device.

I've been doing some reading and it looks like when running metal conduit you only run black and white THHN with no ground, ground the first metal box, and rely on the metal conduit to act as the earth ground for all downstream boxes. Each device just needs to be bonded to the box. Nothing is connected to the ground lug.

I've also seen metal boxes where no grounding is done to the box as long as the switch or outlet has a brass bonding clip on the one leg, then you just ground outlet and everything is grounded.

I've also seen people who are running 12-2 Romex through conduit rather than THHN.

Which is correct?

I assume you can't go wrong with more grounding than less.

I can't speak on the grounding issue, but I do believe running Romex through conduit is a no-go by the NEC when the entire run is conduit. If conduit is used for only a portion as protection it is OK but not for the entire run.

That's my understanding anyway, I could be wrong.

Here in Chicago we run conduit for everything, ground wires aren't necessary but certainly don't hurt. If you are doing the install I'd say run a ground wire because if there is any point in the conduit run that isn't perfectly installed your grounding system is comprised.
And yes running romex in pipe is not only against code but it's pointless use #12 stranded THHN/THWN for the hot/neutral and #14 for the ground

Is the stranded difficult to work with? As far as terminating at the outlets? Then I would ground all of the boxes like normal and ground the receptacles?

I went back to my old thread and folks said Romex in conduit was fine so long as it didn't exceed the fill volume of the conduit. I know there can be heat issues.

Solid conductors and cables in conduit are a PITA to install.
Stranded wire terminates in wire nuts and under screws just fine.
It is a little faster if you purchase devices that use pressure plates and screws (no actual screw wrapping required).
If you run #12 for a 20 amp circuit the ground must also be #12.
The fact it is not required does not grant any relief.

One of the tricks of using stranded is to use strippers to nick the insulation and them twist the insulation off to wind the strands into a tight bundle.

Stranded is much easier to work with, after you strip it twist the strands counterclockwise a couple of times then wrap the wire around the screw clockwise so when you tighten the screw the strands stay put.
Yes ground the boxes and receptacles. And ignore the others, romex in conduit is a nono and doesn't make any sense anyways.

He is correct, my bad

Pull a grounding conductor, I haven't come across a modern raceway installation that doesn't contain one. If you want to pipe the circuit and have a surplus of romex, just strip off the jacket and use it as single conductors (don't fret the fact the individual conductors aren't stamped with any electrical properties)

My technique for stranded conductors with low-end devices or screw terminals. Strip off desired loop insulation then go back and pull up a segment to the end to prevent the strands from fanning out

The vast majority of houses in the Chicago area are all done in conduit and also have no grounding conductors. But like I said before he should pull one anyways.

Sorry to bring up this old post, buttttttt

I assume that with THHN I would need to run conduit all the way to the service panel.

Is there anyway around this? The garage is finished except for the far wall where these outlets will go which is cinderblock.

To save the amount of sheet rock I destroy, could I pull Romex from the panel to an old work box near the ceiling and start running conduit from there?

Something like this....

As long as your romex above the ceiling is installed in a cut in box that is exactly what you want to do. Don't just poke the romex thru the ceiling and into the box extender.