Ok, so this post is gonna be a little misleading. I’m not gonna teach you how to make a weld-in bung from a chunk of soap, or how to carve one out of an old fencepost.
Most of us have bought bungs at some point or another. They are cheap, easy to use, and just make sense. But, I have found that most of the cheaper bungs on the market look like the ones pictured below.
No need to answer that one, I think that anyone who has used a bung like this, especially in a piece of tubing, has run into that problem. I can’t think of how many times I have drilled too large of a hole and dropped a bung into the tubing or had to play the above game to get it lined up exactly where I want it. The other problem with most prefab bungs, is that they are larger than 1/2″ OD, but how many of us own bigger drill bits? While working on a fuel tank mount this week, I decided to build a whole new style of bung.
Since I was mounting a fuel tank, I was planning on a standard 5/16-18 thread. I cranked up the lathe, and made a few bungs just like pictured above. Then I decided to turn down the main section of the bung so that it could easily drop into a 1/2″ OD holes (something I could drill with my standard drill set, and a hand held drill)
I went ahead and got the front mount welded in while I was at it…
Most people would probably like the bungs to sit lower on the frame, but for a tank mount, I like to keep some room under the tank. These give a nice 1/8″ or so under the tank for wiring, zip ties, foam, etc… If that doesn’t work for you, then once you have the “Do It Yourself” bungs installed, you can grind them down lower to the tube.