A fun project - with a great piece of camping gear you'll have for years.

Step 1: A Little Background

Most of my creations are the result of trying to save weight or energy while backpacking. As designated Camp Chef (aka “Maestro”), I’ll also be adding instructables about quick and tasty gourmet food to elevate your camping (or backpacking) experience. For now, here’s an easy and fun project that will impress your friends.

Take a look at the picture to get an idea of the overall concept. I invented this one early one morning before the family was up and using nothing but a small multi-tool managed to make my prototype in about an hour. With the right tools, it should be about a 20 minute operation and you’ll end up with a first-class, lightweight fully functional wine (and cocktail) glass by re-purposing a used water bottle – talk about a real win-win !

Step 2: What You'll Need for This Project

· 0.5 to 1 liter plastic water bottle

· Permanent marker, with holding stand

· Small diagonal cutters

· Ruler and a straightedge,

· Small torpedo level

· Spade drill bit (approx. 1 – 1/8”) and drill

· Small precise scissors

· A dab of clear RTV

· Sandpaper or a small half-round file

Step 3: Measuring and Cutting

A typical cocktail is about 4 ounces of liquid, so using a measuring cup put 4 ounces of liquid into the water bottle (water or whiskey – your choice). Put the cap back on and invert the bottle so all the liquid is at the “top”. Using a permanent marker, held steady in a clamp, slowly rotate the bottle to make a mark slightly above the liquid level. I usually allow about ½”. Your set-up should look like the one shown in the picture.

This marks where the lip of the wine/cocktail glass will be. The next mark will take a little bit of calculation. Empty the bottle (if you filled it with whiskey instead of water – feel free to take a shot), leave the cap off and also remove the little “keeper ring” that originally kept the cap on during shipping. It’s easiest to just cut through it with a pair of diagonal cutters or scissors.

Now you need to take two measurements. First is the distance from the overhanging lip to the mouth of the bottle. In my example, that distance is 12/16”. Next, all plastic bottles have a small dent in the middle of the bottom, so you need to measure the depth of that dent. If you put a straightedge across the bottom and then use a small nail, it’s an easy way to get the measurement. In my case this was 5/16. Now you want to add these two numbers together and then add about ¼” for additional clearance. So in this case we have 12/16 + 5/16 +4/16 = 21/16. I chose to round this number down to 20/16 = 1 ¼ inches total. Using a ruler, measure that distance up from the bottom and mark it, just like you did for the cup portion of the wine glass. Using the permanent marker marking stand, draw a line around the bottle using this mark for a reference.

Whew ! - you have now completed the hardest step in the whole process. Congratulations.

Step 4: Preparing for Assembly

Now on to the fun part. You’ll need to drill a hole through the bottom of the bottle – but not just any hole. It needs to be big enough to get past the threads that hold the cap in place, but small enough to catch on the lip or “collar” of the bottle. You can “eyeball” a spade drill to get the right size, and drill a small pilot hole in the bottom to help the drill stay centered. If you want to be more precise, measure the width of the collar and the maximum width of the threads. In my case the collar was 33mm (1 5/16”) and the threads were 27.4 mm (about 1-1/16”). A 1-1/8” spade drill was just the right size. It’s best to drill the bottle bottom with the bottle cap on, since since a fully assemble structure will be more solid to hold on to while you drill. Plastic cuts fairly easily so make sure that your drill is at the High Torque/Low Speed setting. See the finished hole in the picture. You can see the drilled hole in the base is a little bit rough. I cleaned it up using a half round file to smooth the edges.

The next part isn’t difficult, but it takes a little bit of patience. Using some good scissors cut off the BASE from the bottle. I’ve found that it’s best to start the cut above the mark and then as you cut around the bottle, slowly spiral your way down to the marked line. This seems to give the smoothest result. Once you have cut off the base, then using the same technique, cut off the cup portion of the bottle in the same fashion. Use very fine sandpaper to smooth any rough edges, paying special attention to the lip of the cup.

Step 5: Assemble the Finished Wine Glass

First, try a “dry fit” of the base to the cup as shown above and make sure the top lip of the cup is more-or-less level with the base (it doesn't have to be perfect). If you have trouble fitting the pieces together and it’s a little tight, try to screw the base past the threads. The objective is to get it to bottom on the collar and leave the threads clear. You may need to do some rough sanding or filing on the hole in the middle of the base to achieve this fit. Once you’ve got that part right, then squirt a little bead of RTV around the lip where it will contact the base, making sure that you don't get any on the threads. Again, check that the top of the cup is level with the bottom of the base. At this point let the RTV cure for a couple of hours to ensure that it is fairly well set. Then all you do is screw the cap back on to the bottle top to seal it and you, my friend are the talk of the campground with your superlightweight (mine only weighs 0.6 ounces), supercool, homemade wine glass.

Step 6: Enjoy !

You did an amazing thing turning what would have been a throw-away item into a useful and fun addition to your camping kit. A toast to you and the finished result. Salut !