Wall boxes for sconces

You can use bar boxes, which are more easily adjustable

When I installed a wall lighting fixture I used the rectangular "J-box" usually used for outlets and switches.

You're talking about those fan-stabilizer bar boxes. I wasn't sure if those would fit a normal wall stud spacing or not

Those don't have screws holes for the mounting plate though(???)

See if you can find these at a local electrical distributor:

Paul

No, I'm referring to standard fixture mounting bar boxes. They're made for

Seemed to me that the "mounting plate" (actually a steel strip about 3/4" wide) had holes or slots to mount on the J-box. The mounting arrangements for light fixtures are pretty flexible. There are TWO common sizes of round boxes, for example. If you already have the fixture in hand you can quickly check whether a J-box screw spacing is OK. If you don't have a J-box lying about, just take the cover plate off anyout and measure the screw spacing.

Those look pretty slick, can't find a distributor in Canada though, pity.

PV

Ev:

I like steel boxes, and would use a 4" octagon with a TS bracket, but that's another story.

The regular Carlon boxes can certainly be used, but perhaps a more rigid plastic box like the Carlon Super Blue would deform less and hold its position better:

To help your box position properly, try cutting a small square of your drywall, then holding it against the stud, and holding the box flush with that.

Tap both nails in a bit before driving either one all the way home.

I assume that this is all new work.

Cordially yours: G P

Well I went with the wall brace style. They seem to hold fine and having two locations to mount helps me keep it level.