Enlarge Pipe Airway and Improve Performance

Is it possible to enlarge the airway of a pipe to improve its smoking performance?

Many pipe makers and craftsmen choose to use very small-sized airways to prevent their pipes from smoking too hot. They also use small draft holes to decrease the likelihood of bite damage to the stems. Since standard-sized stems with larger air holes have commensurately thinner bits, they tend to be more susceptible to bite-throughs and breakage in the mouths of those who "chomp" their pipes more tightly (like I do). Pipe makers don't want to get hundreds of returns from customers who mistakenly think the pipes are "cheap" and "break too easily." So they choose to use small, and sometimes very small, draft or air holes. Of course, in some cases, it's simply a matter of poor craftsmanship.

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But an airway that is too small or restricted results in a poor smoking pipe. A restricted draw--one that you have to consciously work at--makes it difficult to keep a pipe lit and nearly impossible to burn to the bottom of the bowl. It can also cause you to puff more vigorously, which leads to excessive heat and tongue bite. And if the airway is too small, the pipe will gurgle far more easily than it should. This is because the condensation builds up more quickly and fills the available space in the shank or stem, causing the unpleasant gurgling.

There are several suggestions I can offer:

• Enlarge the draft hole in the shank up to a maximum 5/32 of an inch (about 4mm). In some cases, this alone will help improve the draw dramatically and help the pipe to burn more effectively and quietly without gurgling. I recommend you enlarge the draft hole in small increments and test it before going all the way to 5/32.

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• If the above suggestion alone doesn't help, you can also enlarge the airway in the stem up to 5/32, assuming the stem is large enough to support this size. Always be conservative when enlarging the airway of a shank or stem. Go in small increments and test each size before going larger. On a straight stem, you can drill from tenon all the way through the bit, if there is enough stem material to support a larger airway. On a bent stem, it is a bit more difficult, but here are a couple options: (a) drill only from the tenon end up to the bend of the stem. Great care is necessary to avoid drilling too far and ruining stem. But if done properly, this can really make a difference. (b) If the bit opening is too tiny but cannot be drilled, you can use an Exacto knife or Dremel tool to carefully enlarge it. Again, be careful not to damage the stem.

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• Use round, abrasive cord (of appropriate thickness, of course) to slowly enlarge the diameter of the airway. Abrasive cord is coated with aluminum oxide and allows smoothing and sanding in hard-to-reach places. You simply run the cord through the stem like a pipe cleaner and sand away the stem material, thus enlarging the opening.

• Straighten the stem (by a careful heating process), then drill it out from tenon to bit (again, assuming there is enough stem material to support a larger size airway). Once drilled, the stem is then rebent. Obviously, this is a risky process and can easily damage or destroy the stem. I have done this successfully, but I only choose it as a last resort.

                   Image Source: instructables.com

• Have the stem replaced and ask the repairman to bore out the airway to the desired diameter. If you're concerned about losing the original indicia and markings, some repairmen are able to replicate/duplicate the logo markings, so it's worth asking.