On closer examination of the QuickCam Messenger, I could see how to disassemble the base. Once disassembled I discovered that there was enough room for a 1/4"-20 nut.
Here is how I modified the QuickCam Messenger so I can mount it on a tripod.
Step 1: Tools and Materials
1. Logitech QuickCam Messenger or another webcam with a suitable base
2.1/16", 1/8", and 1/4" drill bits
3.1/4"-20 hex nut
5.Hobby knives with chisel blades
6.Epoxy Glue or Cyanoacrylate Glue (a.k.a. "Krazy Glue") or Hot Glue
7.Isopropyl (Rubbing) Alcohol for cleaning up epoxy glue
Step 2: Disassembly
Be sure to keep the adhesive of the rubber pad clean so it can be reattached during reassembly.
I've removed the webcam from the base to keep it from getting damaged while modifying the base. The webcam sphere can be removed by simply pulling away from the base and it will detached from the pivot stem.
Step 3: Making Room for the 1/4"-20 Nut
With the hobby knives, cut down the reinforcing webbing in the base's lower half to make room for the nut. First I cut down into the webbing and then cut with the webbing to peel it away.
Continue to remove the webbing until the nut fits flush against the inside of the base's lower half. The plastic is very soft and can be easily carved away with the hobby knife.
Step 4: Drilling the Base
Place the nut in its final location and use it as a guide for the 1/4" drill bit in order to mark where the hole needs to be drilled. Now use the 1/16" bit to drill a pilot hole and use larger and larger drill bits until you finally use the 1/4" drill. Or, to 5/16" if you want make sure nothing binds when mounting on a tripod.
This method will result in a nice and clean hole through the plastic base.
Step 5: Securing the 1/4"-20 Nut
To secure the nut, I preferred to use 5 minute epoxy. Other glues can be used, but cyanoacrylate glue does not have very good sheer strength and might come loose. Hot glue is just too messy for this application.
To prepare the parts for bonding, I scratched the inside of the base and filed the bottom of the nut. These rough surfaces will give the epoxy some extra holding power. Only a small amount of epoxy is required. After all, the webcam weighs nothing and the tripod screw only has to be snug enough to keep the webcam base from moving.
I used a small amount of epoxy between the nut and base and then filled in around the outside of the nut to prevent it from turning. Make sure the epoxy does not get into the threads of the nut. Use isopropyl alcohol and a cotton bud, or paper towel, for cleaning up epoxy if it gets in undesired places. Including your hands and tools.
Step 6: Assembly
Time to reassemble the webcam's base and reattach the webcam to the base.
This was such a simple modification and yet it is apparent that Logitech could have easily designed the QuickCam Messenger's base with this feature. I guess they found the 5 cent nuts too expensive for their $30+ webcams.
The tripod friendly QuickCam Messenger is now ready to be used.
Step 7: Mounting the Webcam
An ordinary mini-tripod for on the workbench. Or, the GorillaPod for when a clutter free workbench is a dream.
I hope you found this Instructable useful.