Step 1: Basic construction of bagpipes
A bag to hold the air
A blowpipe to blow air into the bag
A chanter to play a melody
And a drone which plays a constant note
Step 2: Materials
2 Recorders (or 2 PVC Recorders:http://www.instructables.com/id/PVC-Recorder/)
2 Pens (You can also use a decent sized straw or a piece of hose)
Step 3: Make the blowpipe
Step 4: Trim the Bag
Step 5: Attach blowpipe to bag
Go ahead and tape up 1/4 of the open part of the bag too.
Step 6: Attach The drone
Go ahead and close up the rest of the open part of the bag, making it airtight.
Step 7: Attach the chanter
Attach the other recorder to the hole and this will act as the chanter.