Drill, jigsaw, Tin Snips, Tape Measure, Socket Wrench with ½ Socket, Level, Painters Tape, ¼ inch Drill Bit, #6 counter sink bit, 1 inch wood screws, 1 x ¼ inch bolts/nuts, and 1 ¼ x ¼ inch bolts, nuts, washers.

You can choose any paint you would like to use. I recommend that you use spray paint that adheres well to plastics.
I used 2 cans of Black Krylon Fusion for the base and ½ of a can of Rustoleum Hammered for an aging effect of old rusty iron.

I purchased this plastic chain from Home Depot to hang the cage when it is completed. You could use real chain, but I wanted to keep the rig as light as possible.

PVC Moldings:

I found some PVC type strips that were 12 feet in length in the molding section of the Home Depot.  This is what I used to make the entire cage.

Start by cutting 4 of the moldings at 6ft lengths.  You can see that after you make your cuts the other half of the moldings are slightly longer than 6ft.  That's OK because we want them to be slightly longer.  This will add to the overall look we want.

Make the Rings:

I used the last molding to construct these rings.  You only need 4, but I have 5 here in this picture.  So just make four rings.  Two small ones, one a little bigger than the smaller ones, and one larger ring that is almost shoulder width around.  I taped them with painters tape to hold them in place while I drilled the bolt holes.  More on that later.

Use the jigsaw to make a base:

Take a scrap piece of ¾ inch plywood and place one of the smallest rings on it and trace it out.  Next, remove the ring, cut it out with the jigsaw and fit the ring over the plywood so that the plywood is flush to the bottom of the ring.

Use 1 inch screws to secure the plywood base:

Now you will want to countersink some holes for the wood screws using the drill and #6 counter sink bit.  Next, I just used four 1 inch screws to secure the plywood to the ring.

Get ready to drill!

I taped off my drill bit to keep from penetrating the plywood base too far.  You don't have to do this, but you will want to pre-drill before using the bolts.  You will not need the nuts for the base of the cage.  Just keep them for another project.

Bolt the PVC moldings to the ring base:

OK, you will want to start pre-drilling the holes for the PVC moldings.  Just set it on a level surface and using your level as a guide, begin to drill through the moldings and the ring plywood base.

Bolt moldings to the base ring, alternate the 6ft strips with the longer ones:

Be sure to alternate the PVC moldings as you work your way around the base ring.  This will give the gibbet cage an unique look in the end.

Add ring that is a little larger than the base ring about 1ft above the base ring:

You will want to add the next ring about 1ft above the base.  Making sure to level it and drill it and bolt it in place.

Level out the largest ring and secure it to the cage:

Keep everything as level as you can while you work.  Add the bolts and secure them each with a nut on the backside.

Note: Be careful using the drill!  Don't catch your finger on the bit like I did!

Attach the top ring:

At last we have reached the top of the gibbet cage.  Bolt all moldings down as before with the other three rings, but use the longer 1¼ inch bolts for the 4 moldings that will have the chain attached.  Don't attach the nuts tight yet.  We will need to add the plastic chain to the back.

Use Tin Snips to cut chain to length:

Using Tin Snips, cut the chain into two lengths that you like for hanging the gibbet cage.

Attach the chain with a washer and nut:

Now that you have the plastic chain to the length you like, just attach it to the back of the top ring using a washer and nut.  Take the other end of the chain and attach it to the exact other side of the gibbet cage.

Gibbet Cage without paint:

By now, the gibbet cage should look something like this picture to the right.  Depending on how much beer it took to complete this project, this cage should be somewhat square and symmetrical.

Good job!  Give yourself a pat on the back.  Now it's on to painting.

Spray base coat of black paint:

The painting is up to you.  If you want a dark and creepy looking gibbet cage, follow my instructions.  If you want it to look different, go for it.  Choose your own creepy colors!  For now, we will follow my method.

Finish up the painting with the Hammered Paint:

After you apply the black base, start misting the base with the Hammered paint.  Do this by making quick strokes back and forth following the moldings vertically.  In some areas, you will want to concentrate the Hammered paint, especially on the bolts and nuts.  This will make the PVC moldings really look like rusted iron bars.

Continue the paint on the plastic chain:

This is a close up picture of the paint job.  It also shows the same method was used on the plastic chain to give it that "fresh old look".  You can see the black base shows through in some places, which makes the cage look very weathered.