Ask this question to any piper and you'll be amazed at the different answers you'll get! It's neat to see how different people plan for a variety of situations, but if you're brand new to piping, it can be confusing to know where to start. Fortunately, there are a few common things that most pipers agree are essential tools, and these all boil down to the most common problems that can crop up while you're out and about with your instrument.

Here's a list of the kinds of maintenance and problem-solving you will probably have to do on a regular basis:

Joints and Seals

Problem: Joints can become loose, causing your pipes to leak air or come apart during handling.
What to pack: Hemp, all three types.

Problem: I added more hemp to my tuning pin tenons and now they're really stiff.
What to pack: Cork grease. This comes in a small chapstick-shaped applicator and is great for lubricating your tuning pins so that they slide more easily. You can also simply remove some hemp, providing you are maintaining an airtight seal.

Problem: Blowpipe flapper valve breaks.
What to pack: A spare flapper valve.

Problem: Air is escaping from the pipe bag zipper (obviously this only applies if you have a bag with a zipper).
What to pack: Zipper lube can sometimes fix this problem, if the leak is due to a stubborn zipper that isn't closing all the way. If there is a major leak, it is probably time for a new bag.

Reeds

Problem: Your chanter reed becomes too soft, or too hard.
What to pack: Spare, broken-in chanter reeds, ready to use, as well as some brand new reeds. This is much, much quicker and easier for the beginner than it is to mess with razor blades and awls. You can also pack dental elastics (the ones that are used for braces) and apply them to the blades of the reed, but a note of caution: this can also create a whole separate pitch issue, as elastics will raise the pitch of the reed. I strongly prefer (and recommend) the simultaneous breaking-in of multiple reeds as a better alternative.

Problem: A drone reed finally bites the dust.
What to pack: You can keep spares, but setting them up can take time, so most people just keep corks on hand. If you're careful, a little bit of sticky tack and/or tape on the *inside* of the drone (over the hole in the tuning pin, or, if you prefer to remove the reed and plug the hole at the bottom end) can do this job quite subtly - just be prepared to clean the stock well afterward.

Cleaning and Care

Problem: Your pipes get soaked in an outdoor parade.
What to pack: I like to keep a small bar towel and a fuzzy pipe cleaner (the big ones that are the size of the inside of the bore) in my case for blotting things down. You can also bring bore oil, but I find it's better to be prepared and moisturize the wood regularly as a preventive measure rather than wait until I get caught in the rain.

Problem: Your drone cords pop undone.
What to pack: black hemp can be tied around the cords to attach them, but I find a couple of zip-ties in the appropriate colour is faster. You can always fix it later with thread.

Problem: You had to remove tape from your chanter, and now it's covered in sticky gunk.
What to pack: Goo-gone is super fast, but believe it or not, bore oil will work in a pinch for this. Why bring more than you need to?

Problem: I removed gunk from my chanter, but some of it got lodged in the holes.
What to pack: Pipe cleaners (like the ones from the craft store) are perfect for removing gunk from the holes of the chanter. This is important, because gunk can affect the sound of your chanter more than you might think.

Pitch

Problem: Your chanter is nearly in tune, but one or two notes are sharp.
What to pack: A small roll of tape. Even if you don't know how to adjust the pitch yourself, it can be awfully helpful if you have your own tape on hand so that someone else can help you with this without needing to run off to get things from their own maintenance kit. Scissors are also super ;)

Problem: You think your chanter is flat/sharp but you're not sure.
What to pack: A good bagpipe tuner is an essential tool, both to solve problems, but also just to help you train your ear.

Other Stuff

- I like to have a complete set of large and small corks; this means that I can kill all my drones, or some of them, during a practice for whatever reason. The large corks can be used in place of the chanter, or can be used to store a practice chanter in pieces. Because I teach, I also bring golf tees with me everywhere. You can advance faster by having lots of opportunities to blow drones and practice striking in and cutting off, even if you don't know the tunes.

- I also store things that relate to my particular equipment. I use a hose for moisture control that is designed to be installed through the blowpipe with a special screwdriver. So I bring that screwdriver. If your drone reeds use allan keys, bring those.

- I wear a horsehair sporran with some of my uniforms. So I also bring a hairbrush and a small hair straightener. Neigh!

- Some toiletries are nice to have. I pack deodorant for those hardworking parades and practices. I also put in some sunscreen so I can avoid glen-burn. In the colder seasons, I throw in some Hot-paws hand warmers. Lint brushes and shoe-polish pads are great. Spare buttons for jackets, vests, and spats, and, if you wear them, an extra tassel or two for your ghillie brogues. Those seem to always go missing. Hair products to avoid bad-glen-hair, and Advil, for those pipe band headaches.

Maintenance Kit List

• 6-8 spare chanter reeds, in various stages of being broken-in 
• tape, 2 rolls 
• full set of spare drone reeds (drone-top corks do fine)
• spare practice chanter reeds 
• four large corks 
• three smaller corks 
• pipe cleaners and a miniature bottle-brush 
• small piece of sticky-tack 
• multi-tool 
• awl (for opening the staples on reeds - better to just bring spare reeds) 
• spare flapper valve (*not pictured) 
• screwdriver tool for my moisture-control system (obviously specific to my setup, replace this with whatever yours needs) 
• cork grease 
• bore oil 
• zipper lube 
• black and yellow waxed hemp 
• small pair of scissors 
• small nail file 
• earplugs

This all fits neatly into a tackle-box I bought at the hardware store:

Extras

• - two spare pipe chanters 
• practice chanter, plus one spare practice chanter (just in case I take it out and forget to put it back in!) 
• band book 
• pencils, pens, a pencil sharpener 
• desktop music stand 
• spare poppies 
• lint brush 
• hair straightener 
• sunscreen 
• Tide stain stick 
• ibuprofen 
• spare sgian dubh 
• hairbrush 
• sewing kit 
• plastic rain poncho 
• parade bag (this is a handy "pipe case" that slings over your shoulder, but folds small enough to fit in your sporran) 
• shoe shine sponge 
• Hot Paws self-heating packs 
• towel 
• folding water bottle (*not pictured) 
• band business cards 
• bagpipes

Only pack what you think you need! I tend to over-prepare ;) 

Emergency Bagpipe "First Aid"

Here are the things I tuck into my sporran that I can use to solve most emergencies that might pop up *right* before step-off, when my pipe case and my regular kit is too far away:

• two spare chanter reeds 
• pre-cut tape (if you can find tape with a backing on it and cut it into the right size for your chanter, you won't need scissors) 
• earplugs 
• a mint (pipers can't chew gum!) 
• a hair tie, hair net, bobby pins and barrettes (obviously not required if your hair is short) 
• mini multi-tool 
• zipties 
• band business cards 
• tuner 
• small wallet 
• phone 
• flask 
• my "holy-$h*t kit", which is an easy emergency item you can DIY at home:

• bottom-bobbin sewing spools of black and yellow waxed hemp 
• spare buttons for jackets and spats 
• golf tee (in case something happens to the reed right before step-off) 
• drone cork (in case a drone reed falls into the bag, God forbid) 
• safety pins (for wardrobe malfunctions)