I wanted to add a vise to my workshop, after watching a bunch of how-tos on YouTube (specifically Jay Bates' videos), I gave it a try today.

Here's the materials you'll need for this Instructable:

2 1/2" Pipe Clamp sets
1 1/2" cast iron pipe (I bought a 36" pipe, but you could do anything longer than 24")
Wood for the jaws of the vise (Ideally this would be some kind of hardwood, but as I don't have scraps of hardwood lying around, it would skyrocket the cost of this project. So instead I used a couple 3x2 pieces from a pallet I took apart.)

Step 1: Measure for Mounting

I recently built a workbench for my miter saw and left space for this vise. I measured the opening and it came to just slightly over 26".

Step 2: Cut to Length

I trimmed the ends of both jaws, and then trimmed one board to 26".

Step 3: Align for Pipe Holes and Drill

I lined up where I wanted to drill and used a square to draw lines across both boards. I then measured down from the top to align vertically.

Some how at this point I messed up one of the marks as I would later discover after I drilled the holes and they didn't line up. Oops. But hey, woodworking is about making mistakes and then figuring out how to fix them, right? ...right?

Step 4: Mount Pipe Clamp to Jaws

Drill holes through the metal of the pipe clamp so you can mount them on the jaws. I used washer-head screws.

Pay attention to how you affix the clamp to the wood jaws. You have to make sure that the clamp parts clear the bench.

Step 5: Mount the Fixed Jaw to the Bench

I used a mix of pocket holes and 2 1/2" drywall screws. I made sure the jaw was flush with the front of the bench.

You can see here how I had to enlarge the holes after drilling them slightly off. It would have been easier if I had a drill press, but c'est la vie.

Step 6: All Done!

One the back jaw was mounted, you just slide the pipes in.

Once the pipes are mounted and aligned, your vise is ready to go!