PVC pipe (Home Depot sells 10 ft. length for 70 cents). I use 3/4" inside diameter, but slightly larger for Cockatiels would be fine.

Duct or Masking tape

One 2" Lag screw per perch (I think that's what they're called; they have threads on both ends)

Two washers per perch (wider than the outside diameter of the pvc pipe and the appropriate size
for your cage wire)

One wing nut per perch (to fit the lag screw)

1 bag all purpose sand

1 bag cement

1 tin can or something to hold the molds in.

Now comes the fun part:

Cut the pvc pipe to whatever length perches you want. If you're making more than one,
cut them all at once.

We have a lot of power tools, which makes it much easier. I usually make mine 6" long.
The cut doesn't need to be straight, and my seams usually end up jagged.
I have used wire cutters, scissors, garden shears, and a Dremel to make these cuts.
Take the duct or masking tape and tape the bottom and the seam of each piece of pvc pipe,
so that when you add the cement
mixture, it won't leak out. Stand all of your ready to fill pvc molds in a can, open end up
(I have a piece of 2x4 with holes pre-drilled to hold the molds).

Mix 3 parts sand to 1 part cement and add enough water to make it kinda smooth and pourable.
MIX WELL, and add more water as needed. Pour the mixture into the pvc molds (a little overflow is
better than not filling completely, because some of the water in the mixture will rise to the top).
Place a washer, followed by a wing nut, onto a lag screw, and place it into the center of the cement
mixture. The washer will keep the screw from falling into the cement. Don't worry about any
dribbles down the side of the molds, this is mostly water. Let the cement set for several days,...
the longer the better. If you become over anxious, your perches will fall apart when you take them out
of the mold. I learned this the hard way. Once the cement has set, remove tape