ArtMetal

Hey there! Here are some more postings to your questions: 

You can use an adjustable wrench to lightly tighten the brass part to the torch body if it is necessary. Most often, hand tightening that fitting is all that is needed.

You are talking of the copper tip to the brass fitting. Hand tighten. And then use a vise grip on the copper tip to hold it and to do the tightening. And gently hold the brass part with pliers. Vise grips would never be used on fittings designed to be used with wrenches. But this particular fitting does need a "nudge" to tighten it.

Tip cleaners: you should not need to use a tip cleaner yet. Not unless you submerge the tip in metal or get a speck of metal from a spark into the tip.

Choose a wire from the tip cleaning set and go straight in and straight out of the hole (orifice or tip opening). It should fit easily, don't force. I usually have the oxygen on slightly when I clean it so it blows any dislodged material out. No, you never see the stuff blown out.

Correct assumption: it you ream the cleaner in and out it will actually remove material and make the tip opening larger. It gets a tapered hole, larger at the open end. And that makes for more popping.

If the tip gets bent (dropping it), I consider it to be non-repairable.

If a tip keeps popping even though you have cleaned it and checked all the other things that may cause popping, then I consider it worn out. But you can enlarge the opening to a larger size...If you want.

If it is your own gear, it should last indefinitely.

In my shop, where there may be several classes of beginners in there per semester, there is more wear of course. And although students are shown and taught and supervised, the equipment experiences more wear.

When there is only one operator, (as with an automobile), and that operator is the owner, it lasts longer.

That said, our equipment rarely ever wears out becoming non repairable. Of 25 sets of regulators, we may have one regulator that needs replacement per year maximum. And that is because of the needle "creeping" slightly.

Never do we have to replace torch bodies. And only because we keep a good stockroom do I change tips out from a booth. A lot of popping, easier to replace tip than have student keep trying to clean one that has been used a lot. 

 Popping (backfire) and leaky tip do go together. But there are more things that cause the backfire.

P.S. I love the Capt Kirk snapshot!! VRock