Festool offers a variety of clamps for use with its guide rails and MFT/3. One that might be often overlooked is the Fs-Rapid Clamp. While this is not a clamp that I use often, it does have its place in the toolbox and it can be useful in certain situations where other clamps are not as convenient.
The clamp is made up of two pieces – one end has a trigger that moves one of the spring-loaded jaws forward. The other piece is a fixed jaw.
Either jaw can be positioned anywhere along the guide rail and tightened down with the dame lever. The ends of each jaw have a slight curve to them so that they can grip irregular shaped work pieces and they have a rubber tip to prevent any marring of the wood. To use it you simply install each jaw onto the bottom of the guide rail and tighten it down to the rough width of your work piece. You then squeeze the one-handed trigger to close the jaws and secure the work. To release the clamp you simply press the silver tab with your thumb above the handle. This releases the spring mechanism and the jaw. One of the cool things about this clamp is that the handle can pivot 90 degrees so that it can lay flat against the guide rail. While you can also position the jaws on either end of the guide rail, you need to make sure that the trigger is on the right when the rail is upside down to ensure that it does not lay over the anti-splinter guard when positioned flat.
The clamp exerts a decent amount of pressure to hold the work securely. As you can see from the photos, I can stand the guide rail on edge or on its side and the work does not move. I used some smaller panels and boards to illustrate how the clamp works, but I find that this clamp really excels at holding the guide rail securely when cutting sheet goods.
I know that many users rely on the rubber strips on the bottom of the guide rail to hold it while cutting and forego any clamping. However, when I use expensive sheet goods or when I am cutting something that I cannot afford to screw up (like the top of my desk), this clamp earns its keep. Since it clamps on the edge of work piece, I do not risk marring the bottom of the sheet good or panel and I can still secure the rail so that it does not move. Since it is one handed, I can square my rail and squeeze the clamp tight without accidentally moving the rail. Using screw clamps or even the quick release clamps I have found that I can accidentally push the rail just a hair out of square when tightening and this can be an exercise in frustration getting it just right. I find that the quick clamp makes this process easier. One other place where this clamp is useful is if you need to trim a door or the side of a cabinet or box. You can clamp the rail horizontally or vertically on its side and hold it in place to make the cut. Finally, when cutting sheet goods I find it easier to adjust my rail and rely on squeezing the clamp to secure everything rather than going to one side, tightening the screw clamp or quick clamp and then going to the other side to do the same thing. I can align my rail, tighten and start the cut from one position.
I think that the Fs-Rapid Clamp is a worthy addition to your clamp collection and it adds some versatility that other clamps cannot provide.