If you have a Wanhao I3, Balco printer, Cocoon or any of the clones that are the same for these machines, you will know that the filament holder they give you is only good for small 250gm or 1/4 size filaments. I buy my filaments in 1kg rolls, and they are wider than the holder, so this is how I made my own for a few bucks.
This is my first Instructable so I hope I get this right.
Step 1: Items to Get.
Start by getting a 25mm outside diameter pipe. I found mine in the hardware store in the watering irrigation section. While there, also get a 25mm end stop to go on the end. The other side is a connector which usually goes from the pipe to a valve. The screw section is just the right size for the hole where the original holder goes in, and it has a flange which will act as a stopper. The other part is an end screw which will fit nicely on the screw end of the valve thread.
Step 2: Note the Taper and Correct It.
One thing I noticed about the thread on the valve part is that it is slightly tapered. This is to ensure a tight fit to the valve where my finger is. If you use a file lightly on the end near the join, you can make it the same size all along so the thread will go on easy.
Step 3: Attach Pipe and Cut End Off End Cap
I cut my tube about 12-13cm long so it fits the new reels with plenty to spare, then glued the valve attachment on. With the threaded end part (in black) it needs the enclosed end cut off so you can use this as a lock nut. If you leave the end on, you will not be able to tighten it completely.
Step 4: Check Nut Goes on All the Way
Check that the nut goes on the end easily then unscrew again. Put the thread through the hole where the original one was, put the nut on and tighten. I coloured mine black with spray paint and let it dry before I put it on to match the rest of the unit and also be the same colour as the original.
Step 5: Place End Cap on - DO NOT GLUE!
Put the end cap on but do not glue it. It is designed for a pull off/push on to stop the filament reel from working it's way off the end. If you glue the end on, you will not be able to put the reel over the end.
Step 6: Finished Product
This is how the finished product will look. It's a simple project and I have done it twice on both of my printers and it works very well. I hope you give it a try.