1/2" compression with plastic sleeve and nut
15" of copper pipe 1/2" with 1/2" cap (grind to within 1" at each end)
14 3/4" plastic tubing 1/2" outside dimension
1/2" x 1/2" female elbow
1/2" male pipe thread x 1/2" compression adapter
1/2" male pipe thread x 3/8" compression adapter
1/2" o-ring or similar washer
The first step is to cut a length of 1/2" copper pipe to 15" and grind the copper down the length so that you go through the pipe leaving a narrow channel. I used a table top belt sander for this process. Before you start grinding, mark with a sharpie two lines 1" from each end. This will keep you from grinding off the metal too close to the ends. As you grind or sand away the material keep track of how deep you have gone, at a certain point you will have sanded through the body but a thin layer of copper will still be covering this area and you should scrape or cut this material out so you can see your progress better. The idea is to get a straight even channel cut out stopping short of each end. To see a video on making this extruded copper piece, go here. When the grinding is done, the hard part is over. Solder the 1/2" cap to one end. If you don't solder, it's no problem, just crimp the cap very slightly and press in place. Next, after applying teflon tape, screw the 3/8" and 1/2" compression adapters into the 1/2" elbow and tighten. Next, slip the 1/2" nut and plastic sleeve onto the plastic tubing and secure the tubing to the adapter that is now in the elbow. You can now slip the copper tubing over the plastic tubing.
You will need to drill a 3/8" hole in your keggle or pot to attach the elbow. I positioned mine low on the keg but above the radius area, where the side get flat (if that makes sense). I drilled a 3/16" pilot hole followed by the 3/8" bit. Some suggest using oil or water where you drill the hole to help in the process but I just drill through and had no problem. You also need to drill a 3/16" hole in the upper apron of the keg to install the eye bolt. This should be directly above the other hole and the eye bolt will be installed here to hold the upper end of the sight glass in place.
Place the rubber washer on the 3/8" compression adapter and push threaded portion through the keg. From the inside of the keg, attach 3/8" compression nut and tighten. Install eye bolt over the top of the sight glass. You will adjust the depth of the eye bolt by first screwing on one of the nuts then after pushing the eye bolt through the hole you drilled and attaching the other nut on the inside of the apron. Loosen or tighten the outer nut to adjust the depth.
That's it. You now have a sight glass. I hope the
pictures help because after reading what I just
wrote, even I am confused. Good luck. Since this post I've come up with an alternative that is better and easier.
If you have any questions, leave them in the comment area below.
P.S. If you're enjoy Beer Diary... please support it
thought my advertising sponsers. Thanks.