This simple tool is very handy for holding small parts for cutting on the CNC router. I also find it useful for drilling holes and other jobs where I need to hold a small part in place. I made mine from materials I had lying around the garage. I was very easy to make, basically cost me nothing, and was well worth the effort.
This vise was featured in my last instructable on CNC Engraving.
Step 1: Materials
Long machine screws
The thickness of the jaws is basically the width of the square nut. Otherwise the sizes of these parts is up to you based on what you want to hold and what materials you have available. For example, Imade my jaws from scrap poplar, approx 8mm x 10mm x 100mm (5/16"x3/8"x4"). My plywood base is about 16mm (5/8") thick and 100mm x 300mm (4"x12"). My machine screws are 10-24 because that is what I have on hand. This is close to M5 x 0.8 in size.
Step 2: Drill Some Holes
Drill two holes through each jaw, through the narrowest face, one near each end. Make sure the holes are in the same places on both jaws so they line up. You should be able to pass the machine screws through both holes of both jaws simultaneously without binding. The diameter of the drill bit should be slightly larger than the screw thread (major) diameter. In my case, I used 13/64".
Then I pre-drilled holes in the side for wood screws. I more or less centered the screws on the top face of the jaw and spaced them evenly between the big screw holes on the side face. The size of pilot holes depends on the screws you use, roughly half the body diameter (not including the threads).
To get the lowest possible profile, I used a countersink bit to countersink the holes for the wood screw heads.
Step 3: Assemble the Parts
Screw or glue one of the jaws down to the base with the holes for machine screws oriented horizontally. If using wood scres to fasten the jaw to the base, I recommend pre-drilling the screw holes. For this, I placed the jaw where I wanted it on the base (parallel to one edge) and then used the jaws as a template to drill small holes in the base.
Align the other jaw to the first and insert the machine screws through both jaws. Thread the screws into the nuts, which will slide along the base as you tighten the screws.
Please ignore the large holes in the photos of the base. These were left over from another project and aren't essential to this one. You may very well find it useful to drill some more holes in the base depending on how you want to clamp it down.
Step 4: Send It Into Action!
Loosen the machine screws enough to place your stock between the jaws. Tighten both screws until the jaws are gripping the stock. Try to tighten the screws evenly to maintain even pressure across the jaws.
The flat base makes a convenient surface to clamp down with toe clamps or screws. It can also slide against a fence, or serve as a handheld fixture to keep your hands safely away from moving parts.
If you like this style of step-by-step instruction, please share with others and subscribe, so you'll be notified when I post more. If you have questions, please post them in the comments. I will try to answer and probably update the instructions, too. Read about more of my woodworking projects and tools at ChipsWoodShop.com.