Try replacing your old bar clamp with a band clamp.
Band clamps are strips of flat strap threaded through a metal clasp with a tightening nut. When the nut is tightened, it pulls the strap through the clasp and locks it there with each turn of the nut. Band clamps are efficient and are typically used in woodworking to clamp odd shapes, as they squeeze equally from all sides. They make excellent substitutes for bar clamps, even though they don't have the raw torque of bar clamps.
Instructions
1. Press on the center of the clasp to open a small jaw that releases the strap. Pull the strap through the clasp, making a circle. Open the circle large enough to fit over your project and drop it over the project. Let go of the clasp.
2. Use your fingers to position the strap where you would normally place the jaws of a bar clamp. Open the clasp again by pushing on the center. With the other hand, pull the strap to tighten it so it stays in place.
3. Turn the tightening nut five turns clockwise with the wrench. You will hear five clicks with each turn of the wrench. Watch the strap begin to stretch and tighten.
4. Adjust the strap again before it gets too tight to move. Make sure it's in the exact place that you want it.
5. Turn the wrench clockwise, watching the strap tighten with each click. When the strap gets hard to turn with the wrench, pluck the strap. If the strap sounds like a guitar string, it is tight enough.
