Common Pipe Flaws: What Makes a Bad Pipe?

+1 narrow airway. Had a beautiful slightly bent Dublin, beautiful slender pipe with an ample bowl, and quite light weight, but it always removed and retained pipe cleaner fluff. I took it apart every time I smoked it and tried various brands of pipe cleaners and wire for a pipe cleaner, etc. I finally traded the pipe before it installed itself on my racks and I avoided it forever. I could have tried boring it bigger, but I was afraid I'd thin the stem dangerously. Just cut my loses and made a little in trade.
I also traded a Sav bulldog that was just too shapeless, no bead line, not much shaping to the bulldog bowl. Finally I just unloaded it. Only Sav I've ever unloaded.

The most important thing is that the two holes actually meet inside the briar, ha ha.

Actually, I have a Tinsky that I have to re-glue his little star back onto the stem every now and then. Another issue that I had with that pipe was that the maple stem adornment just fell apart on me before I got it home. It was just glued on also with the hole drilled through it and the briar, with no mechanical design to help the spalted maple stay on. There is a whole other epic thread on that pipe. But, he eventually glued it back on for me and I still smoke it.
But, things that irritate me are thick stems also and low profile buttons that make it hard to clench. Heavy pipes that I have to hold. Burs inside the draft of the stummel that catch on the pipecleaners, leaving fuzzies inside the pipe.
There are other things that I look for, but for the most part, these are deal killers for me.

When it falls out of your mouth while backing up and the left front wheel rides over it. Now you have a really bad pipe!

In addition to the other things already mentioned
1. Pipe cleaner doesn't go through
2. Hole not drilled to the base of the bowl
3. Stem not having a good comfortable button
4. Pipe being too heavy for its size (clearly a personal preference)
5. Stem and stummel do not fit well
A little less obvious, and certainly more for personal preference, the pipe just doesn't fit well in my hand

Since another forum member told me about slinging out any water that may get start a gurgle, I don't ever have to use a pipecleaner while smoking. While my first experiment for this was to try it in my girlfriend's livingroom right in front of here, leaving a string of brown water to stain her carpet, OooooppppS!! I can just step outside and give a sling, which saves me from having to constantly carry pipecleaners with me when I smoke. So, passing a pipecleaner isn't a deal killer for me.
Just put a finger over the bowl and snap your wrist. Any droplets in the stem just clears without an issue. I sweep and mop the floor of my studio three times or more during the day, so the little droplets of water aren't an issue most of the time that I am smoking.

In my experience a problem airway is the only thing that makes a truly bad pipe. Restriction is the biggest issue, but off-center draft holes can have irritating effects on burning and cake formation.
Bowl finishes that inhibit heat dissipation also detract from a pipe, but they are not nearly as bad as a troubled airway.
cosmicfolklore, I bought a Tinsky to serve as my son's birth year pipe. I hope that pipe does not develop the problems yours had.

All of the above. A "pinched" stem where the bend has constricted the airway is a real pain and ruins a pipe more than most things. That should never happen. I've also had pipes with stems that are too tight to remove and that bothers me - how did the pipemaker not notice and fix this? Every pipemaker has a different way of making the lip at the end of the mouthpiece, and some are too low or too high or too thick to be comfortable, and it makes a big difference to the comfort of the pipe. Also, I have some pipes where the stain comes off on my hands - shouldn't happen. Poor quality ebonite in stems is also irritating, and some pipe stems oxidize far quicker than they should.
I'm not overly fussed about cosmetic issues that don't affect the function, but a roughly finished bowl or splashes of stain inside the bowl tell you something about the pipemaker's priorities. Then again, Peter Heeschen's pipes are like this and they are great.
Shaping is very important to me - the lines and balance of a pipe shape matter. Some pipemakers have a great eye for this, others not. The bowl-to-shank transition is a common area where the pipe shape can go wrong, as is the shape and flow of the shank and stem. Some pipemakers are quite unrefined in shaping and leave too much briar on so that they look clunky and amateurish.
I've experienced all of these issues with expensive pipes from highly reputed makers, not just on factory pipes. I won't name names. I just notice the issues and it puts me off buying another from the pipemaker.
Some of the things I see that show extra care and attention, and which make a difference for me include:

- highly polished airway inside the shank - I think this improves the smoke noticeably

- placement of the stummel in the briar block, to get the best of the grain or sandblast

- highly polished stems and bowls - probably a lot of work but when you see a pipe stem that looks like liquid or a well finished bowl, you feel like the pipe is in a different league

What do you mean by 'bad pipe?' Are you referring to a pipe that is poorly engineered, poorly crafted, or poorly designed aesthetically? My answer would be different for each one.

Maybe I've been lucky, or maybe I'm just easy to please, but I've encountered few really bad pipes. Of the characteristics that I find objectionable, the foremost is a tight draw. One's head should not be in jeopardy of implosion when trying to draw a bit of smoke. As most of this seems to happen at the bit, careful filing of the airway to open it usually fixes the problem. A thick or too round stem at the bit is unpleasant, but as I also smoke pipes that are 100 years old or older, I accept the technology of that era and adjust accordingly. I dislike a button that is too slight to provide an adequate grip.

I've had pipes that get hot just from looking at them and a few pipes that seem to have a preternatural ability to deaden the flavor of anything put in them. The pipe cleaner test is not a deal breaker as I have some great smokers that won't pass that test.

Drilling the airway flush with the bottom of the bowl is not advised with an extreme bent unless you like slurping brown juice with your smoke. It's like sticking a straw in the bottom of the glass. For those concerned, that's why pipe rocks were created.

The tenon should largely fill the mortise and the airway should ideally be smooth from one end to the other.

I'm not a fan of either Dublins or Bulldogs because they're rarely drilled with conical chambers, thus creating very unequal wall thickness that can lead to overheating at the base, shrinkage and burn out. No issue with that shape if it's drilled with a conical chamber.

There are some things I avoid like the plague.
#1 - over loose or over tight stems

#2 - Fills :? nothing makes me question a pipe more than a big fill in the briar.

#3 - Will it pass a cleaner. this is just good engineering and layout to me. And also why I love Savinelli so much.

+1 Sablebrush ...well, except for the bully and dub bash at the end, ha ha. I had never thought of bulldogs as having conical chambers though. I will have to recheck that when I get back home. I use my bulldogs for latakias and mixtures, because they have massive .75"-.8" bowls, ha ha. I know that's not massive by some people's standards, but compared to my tall and tight Dublin cones, it is.

I don't have any bad pipes as such. The ones that get used, its all about what goes in the mouth. If it feels good I smoke it. Too wide, too thick or too hard on the teeth I dont. Blimey that sounds terrible

Bad pipes I have owned: Several that smoked hot no matter what tobacco, how it's packed or how slow it is smoked. A wood problem in my mind. One that tasted harsh with a weird after taste even after trying to smoke my way out of it for 2 years. Again, the wood.

Ditto on draft hole being flush with the floor of the bowl.
Stem fit - not to too snug or loose. Got a chacom that never tightened up.
Stain - Had a Joh's that tainted my fingers orange every time I smoked it. Happened for weeks.
Weight - This is personal but I like my pipes to come in at about 50 grams or less. Will some exceptions.

Wall size proportionate to bowl. I used to like wide bowls on the theory that they smoked/handled cooler than thin walled pipes. Now, I'm realizing that hot bowls has more to do with age/quality of the brier and smoking pace.
Low contrast, muddied grain - Again personal but I like grain to standout.
Ill defined sand blasts - Like distinct rings and grain. Can't tell the difference with some SB from some rusticated.
Rounded or sharp stems - Both uncomfortable
Bent pipes that don' hang properly - If not balanced properly, the weight of the pipe will leverage the stem against the back of your top teeth or require too much bite when clenching.
Narrow airways resulting in tight draws - I shouldn't have to drill it out.
Pax

One problem I constantly run into with Peterson, much as I admire their pipes, is they really crank those stems on tight. Maybe it's just the fact that my grip isn't what it used to be. But a while back I send the Petersons I had at the time to shantiques to sand down the stems slightly so they could be removed by someone other than Hercules. Up to then, and still now with newer Petersons, I have to put them in the freezer for a few minutes before I can remove stems. I wonder why they haven't resolved this problem, or if everyone else just has a stronger grip than I. Yet, I have no problems disassembling my other pipes.

I've only had one pipe with problems with the air draw. This was a giant Nording, a very handsome giant panel, and again shantiques came to the rescue by slightly enlarging the draft hole. Pictured below, I think you'll agree this pipe was worth saving.