Burnt Latke
threading a propane valve

If you've made the decision to move up to direct propane, you're going to have to thread a propane valve. This can be easy or impossible. The outcome depends on your skills and the tools you own...or borrow.


Buy yourself a new Bernz-O-Matic torch head then take a hack saw and cut off the tip. Cut it right below the bend so you end up with a straight stub. To create the threads, you will use a die like the one pictured left. It is important to use only a 1/8" NPT (National Pipe Thread) die. You will need to buy this item, unless you're a plumber...or know one. There are two types of dies. One for cutting threads in round tubes ($15-25) and one for chasing (cleaning up) existing threads ($5-7). The propane stud is a soft brass and it is possible to cut the threads with a chasing die. This will trash your die after a few uses, stick it into a potato and launch it.

When using a chasing die to cut, sometimes you need to give it a little help. Use a Dremel or grinder to take down the diameter of the stub slightly and taper the tip to a point around the edge. This will help the stub fit into the die. Ideally, you would use a vise with a jig to safely hold the nozzle, then use a proper die wrench to apply downward pressure and turn the threads.

Ghetto vise2

If you do not own these tools, it is possible to hold the die with a wrench or vise grips then turn the threads with another wrench. Use a small piece of wood with a hole drilled in it to provide downward pressure. When it finally starts cutting, make sure the nozzle is straight. Work slowly, especially at first. Cut a quarter turn forward then back up, another quarter turn forward, back up.

Ghetto vise 1

Use a cutting oil to lubricate the cutting area, 3in1 oil works also. If it squeaks, add more oil. Keep the threads and die clear of brass shavings. If using the ghetto vise pictured here, the stub will bottom out on the table top. Add a couple wood blocks (pencils) under the edges of the die to elevate it. Continue cutting threads to the depth of your 1/8" fitting.

NPT fittings have tapered threads to help seal leaks Unfortunately the short length of the stub prevents some dies from cutting enough deep threads. The solution is to turn the die over and carefully, by hand, cut a few more good ones yourself. Polish the threads with a Dremel and buffing pad to remove any rough spots. Don't worry, your second one will be much easier.

finished valve