Klemmsia Cam-Action Clamp - Tool Review
by Jeffrey Fleisher
New Market, VA
Click on any picture to see a larger version.
The Klemmsia Cam-Action Clamp provides a unique clamping action that is both surprisingly strong as well as easy.
The clamps are built of galvanized steel and beech with cork lined clamp heads. They come in a variety of jaw sizes and bar lengths. The standard jaw size is 4-1/4" wide and comes in bar lengths of 7-3/4", 15-1/2", 23" and 31". The deep set jaw is 7-3/4" wide and the bar is 7-3/4" long. There is also an interesting configuration that has two cam-action heads on the same clamp.
The heads on this clamp are 4-1/4" deep and the bar is 38-3/4" long. The manufacturer states that these clamps have been made in Germany for 75 years.
The cam-action mechanism, which is the heart of this type of clamp, is pretty easy to understand. A wooden handle has a rounded end that is slightly offset which provides the cam-action. The cam is located under a piece of wood that is partially cut from the main body of the wooden bar. As the wooden handle rotates up, the cam presses against the wood 'slice' and presses it up. This provides the clamping pressure when something is placed between the cam-action head and its mating head which is fixed (except for the dual action head clamp). Although I don't have the equipment to measure the forces that are created by this type of clamp, my informal analysis is that they provide more than enough pressure to keep two surfaces together for your typical glue-up. You won't use this clamp to 'force' two surfaces together but you shouldn't be doing that in any case.
This clamp can be used for conventional clamping situations. As shown in this manufacturer photograph it is very easy to position glued up boards between the jaws of the clamp and the cork covered pads provide uniform pressure across the joint.
I often use this clamp when quick on and off pressure is required as in clamping a board to the bench for chopping out dovetails. I often need to re-position the board quickly and rotating the cam-action lever allows me to do this easily. The deeper depth of the 7-3/4" jaws are nice to apply pressure to the center of the board.
However, with all that being said, this style of clamp really shines when clamping irregular shape surfaces. Have you ever tried clamping something with those clamps that have the little rotating disk on the end of the arm that moves in every direction but the one you want or worse, moves when you want it to stay stationary? Seems like you need to hold the clamping pad stationary with one hand while you hold the boards with your other hand and then twist the handle with your third hand!!
Now, you don't normally try to clamp two dowels together but this really shows you what I mean.
This look familiar? As you twist the handle of the clamp the disk rotates and also typically slides off the side of a curved or irregular surface. With the Klemmsia cam-action clamp, there is no twisting or rotating heads. All the pressure is exerted in-line with the clamping pads which makes this type of clamp-up trivial.
This is even true for unequal surfaces as shown here. Now I don't expect you to be gluing dowels together as shown here but these are the first clamps I reach for when I have a clamping setup that contains surfaces that are not straight and square.
I'm sure everyone has heard the saying, "You can't have too many clamps", which normally means the number of clamps in your shop. I'll add that you can't have too big a variety of clamps as well. These clamps are a definite must for any shop.
CLICK HERE to find out more about Klemmsia Cam-Action Clamps
Jeffrey Fleisher has been a woodworker for approximately 20 years and a professional woodworker for the past 6 years. He is the president of his local woodturning club, the Woodturners of the Virginias and past president of the Northern Virginia Carvers. You can see some of the furniture he has made at www.jeffswooddesigns.com. He can be reached by email at email@example.com.