One common problem encountered in woodworking is that the clamps often used to secure stock quite often get in the way. This causes the woodworker to have to reposition them which takes time and effort. A vacuum clamp overcomes this problem by clamping the stock from an area underneath the stock.
|The V-Clamp is a small venturi operated vacuum
clamp. It is designed for holding both small and large (non porous) material which can
then be worked by other tools. Although the full clamping area is rather small at 8"
x 6", it can be made smaller yet by reconfiguring the seal or effectively increased
in size by adding another clamp to the system. The standard VC4 model is one sided and
must be fixed to some other surface to be used; molded in mounting tabs are included for
this. The VC5 on the other hand is two sided and can be used on any flat work surface. The
clamps are supplied with a length of air hose & fitting, an extra seal, and the
instruction booklet. Both the VC4 and VC5 operate and perform the same except for the two
sided aspect of the VC5; consider what is written herein applying to both otherwise.
|The venturi design means that in order to work, air must be flowing through the device at all times. If the exhaust port of the venturi is covered it will also loose vacuum. This can also be used to advantage to cycle parts off and onto the clamp without disconnecting the supply or turning a valve. The manual recommends an 80 to 120 psi air supply to clamp parts. I found that much less can be used with good results; I typically used 50 - 60psi. Using less air pressure will keep the air compressor from having to cycle as often. The CFM requirement and noise seems lower compared to my shop-made venturi system.|
|As mentioned, the clamps are relatively small; they are about 7/8" thick and on large or long pieces some sort of support would be needed to keep the stock from becoming a lever which would break the vacuum. This is a relatively minor problem and if only one clamp was available I recommend making some spacer blocks to be placed underneath the stock for such occasions.|
|Even though the clamp area is small, it might be
too large for a particular piece of stock. To overcome this, the seal can be reconfigured.
Although the seal looks like a giant O-ring in pictures, it is actually just a simple
length of EPDM sponge rubber. The seal can be wrapped around any of the nine sections of
the base and as long as the "first" section is included and the configuration is
closed it will work. Depending on the operation being performed, one might also want the
stock elevated to keep from running the cutter into the base; this can be done with a
To achieve the greatest benefit from the system, it should be setup ready to be used at a moments notice. Although all tools benefit from this same situation, the V-Clamp is a tool that just begs to be built into a workbench or other fixture to achieve this end. In effect, to take the most advantage from the tool the shop itself would be designed to accommodate it.
In the shop I never encountered any instance where I could break the clamping action under normal use. As soon as the V-Clamp is used for the first operation ideas on how to use and mount the tool for best effect start to circulate. I've used shop-made vacuum jigs before but this commercial tool performs much better. This is mainly due to the material used for the seal and the easy to reconfigure nature of the design.
A careful reader of this site will note that there are very few tools that I recommend without reservation; the V-Clamp is one of these tools. Although it isn't inexpensive the utility of the tool is exceptional. It is also very well made and should last forever. Your application will determine which model is best for you. Although this is true of any tool, it is especially true of this type of tool, the easier it is to access the greater the benefit the owner will have from it. I also highly recommend the valve accessory which is much easier to work with than a standard plumbing valve.
In the interest of full disclosure V-Clamp provided this product to facilitate this review.