The picture above shows how the parts fit together. Note that the dowel does not actually support the weight of the frame, it merely keeps it snugly against the wall.
~ by IllinoisOwl
You may also be interested in creating an IKEA RIBBA photo gallery
Don’t throw the RIBBA backing paper away just yet. It is really useful in marking the photo gallery layout on the wall. Once you’re happy with the shape and mix of frames, you can start hammering or drilling the walls. Get the full photo gallery tutorial from IKEA.