How to make a rod puppet no visible strings

Ok so I have wanted to make a rod puppet for some time now.  I wanted to try and make a mech that didn't have any visible strings.  

So I started with about a 18 inch long piece of 1/2 inch pvc pipe.
This will be the inside piece, and it will be the neck and hold the head.

Also about a 8 inch piece of a coat hanger.  It tried to get it as straight as I could get it.

About two or three inches down I drilled a 3/32 hole all the way through.  

Then I bent the coat hanger into this shape. This is going to be the bottom jaw. The loop will be used for the spring, and for the string that opens and closes it.

I spread the sides of the coathanger apart and put them in the hole I just drilled.

Then i drilled a 7/16 inch hole all the way through just above where the wires went in.

Then I put a dowel rod in the hole.  This is going to be the top jaw.

I took a spring out of a click pen that didnt write anymore. I hooked that to the loop in the coat hanger and stretched the spring to see where it needed to go.  I drilled another hole for a small bolt and attached the spring to it.

Now when I pull down on the mouth it...

springs back closed

I drilled another small hole underneath the bottom jaw.  This is where the string will go through.

Near the bottom I drilled another small hole. This is where the  string will exit.  I also took another piece of coat hanger and made a trigger.  The same way I made the bottom jaw, except no loop.  Looking back I probably should have made a loop in this one too. I ended up taking this trigger off and putting it on the next piece. 

This starts the beginning of the outside piece.
The outside piece will have the puppet's body attached to it.

Then I took a 1 inch pvc pipe cap and drilled a hole big enough for a 1/2 inch pvc to go through it.  I want to say it was 7/16 but I am not sure. This is going to attach to the top of the outside pipe. The hole in the cap keeps the inside pipe centered. The hole is also slightly bigger than the smaller pipe which will allow it to turn.

I took a longer piece of 1 inch pvc. This is going to be the outside of the mech.
 I measured where the trigger should be. Then behind that and a little higher I cut a slit.

I cut a half a piece of pvc and sanded the edges. I put a bolt through it and epoxied them together.

This is the handle and the trigger.

On the front of the outside piece I cut out a half section about an inch long.This is where the string will come through.  You can see I have already threaded the string through.  My kids invaded the shop about this time so I was more focused on keeping them safe than I was on taking pictures.
I used a piece of picture hanging wire originally but it was too stiff, so I then I used a piece of string.

As you can see I attached the thumb control to the 1/2 inch pvc. This allows the head to turn side to side while still opening and closing the mouth.
This also keeps the inside pipe from sliding out of position.

Testing...

It works!!!
The next time I think I will make a more comfortable grip.  That is my only complaint.