Transform a Ballpoint Pen Into a Survival Whistle Mini-pen

This Instructable shows you how to transform a common ballpoint pen into a survival whistle which will fit inside an Altoids tin and still work as a pen. This multi-functionality helps to save space in the tight confines of the tin.

DISCLAIMER: Though this whistle is ear-splittingly loud when configured properly, I have not tested it in a survival situation. Please use your own judgment on whether your end product is good enough for a real survival situation, if that is its intended use. If it isn't good enough for that, please consider shelling out the money for a factory-made whistle.

Here are some pages I viewed which were very helpful in learning about the construction of whistles:
https://www.instructables.com/id/Loud-Easy-Simple-Whistle-Bic-Pen/
https://www.instructables.com/id/Make-your-own-whistle
http://www.ggwhistles.com/howto/
http://www.jonsbushcraft.com/elderwhistle.htm
http://www.e-scoutcraft.com/wood_carving/whistle.html

Consumable materials:
--small piece of sandpaper
--glue (optional)
--Papermate Eagle ballpoint pen
   --it is quite possible there are other pens which will also work; I have selected this one for several qualities. First, there is no hole in the barrel of the pen--for some reason many ballpoint pens have a tiny round hole somewhere on it. Second, the ink cartridge is easily removed with your fingers. Third, the end piece is a separate piece that can pop out.

Tools:
--scissors
--pliers
--knife
--ruler
--marker

After removing the cap, pull the ink cartridge out of the pen with your fingers. Most of the ones I have made have come out VERY easily, but there were a few that resisted removal. I would suggest if you have one that resists removal you might want to save that for regular pen usage.

Mark the pen barrel at 2 1/8 inches from the start of the straight part of the barrel. Cut at this point with scissors. Be careful--one or both pieces are liable to go flying off into the nether regions of your room. For the purposes of this tutorial, I will call these two pieces the mini-pen barrel and the original end piece.

Sand the cut end of your mini-pen barrel until it is basically smooth and even.

Place a mark at about 3/4 of an inch from the original end piece. Cut here with scissors. This also poses a projectile hazard. After you find it, set aside the larger middle piece for later use.

Grip the small original end piece with your pliers, on the open side. Squeeze with the pliers, rotating as necessary, to force the black end cap to slide out. Discard the squeezed plastic; retain the end cap.

Insert the black end cap into the mini-pen barrel.

Using your knife, cut a line perpendicular to the mini-pen barrel. This cut is called the window. The positioning of this cut is immediately at the point where the black end cap ends on the inside of the pen. Go about 1/3 to 1/2 of the way through the pen barrel.

Holding your pen upright, or angled slightly, use your knife to cut at about a 45 degree angle aiming towards the bottom of your prior perpendicular cut. This ends up being about a 1/4 inch from the perpendicular cut. This cut is called the lip. It is better to cut too little than too much. If your whistle does not sound correct, this is one parameter you can fix--you can increase the cut/lip.

Next we will start on making an air passage, called a windway.

If possible, remove the end cap. You can sometimes remove it at this point by using the point of the lid, or some other pointy tool. Be careful, though, as there is the possibility of snapping off the cut end of your barrel. If you cannot remove the end cap, that is fine. You can do this step either way.

If you can remove the end cap, you can use your scissors to cut just over a third of the middle of your barrel end out, making a mushroom shape when looking at it straight down. If you cannot remove the cap, use your knife to shave down that same area. This is part one of the windway.

Grip the end cap with your pliers so that one side is available for sanding. Sand the side of the end cap until there is at most a quarter of the side gone. The end cap of the Eagle pen is hollow, so if you go too far you will ruin this end cap and have to start over. You can always sand more later if you did not sand enough. This is the other part of the windway.

Reinsert the end cap into the end of the barrel, lining up the sanded area with the cut area to make your complete windway. Later after you are satisfied with everything, you can use glue to keep the end cap firmly in the position desired. It is not required, however, as it is pretty sturdy even without glue.

Go back to the original middle section you set aside. Measure out about 9/16, and cut. This 9/16 length will be your mouthpiece section. Lightly sand both ends of this piece to remove any jagged areas.

Use your scissors to cut the mouthpiece section down the length of one side.

Cut a tiny bit of the corners off one side of the mouthpiece, on either side of your middle cut. Sand these lightly to remove jagged edges.

You can use your original pen lid to force open the mouthpiece enough to get it over the end of your whistle. The positioning of the mouthpiece will be a variable you will have to adjust. Look at the next step for troubleshooting ideas.

Positioning of the mouthpiece
--You can move it forward and backwards to figure out the area which produces the loudest tone.

Plugging the end
--Some whistles end up being loudest when you plug the other end with your finger, some when you don't plug the end.

Holding mouthpiece
--Sometimes it helps to hold the mouthpiece tightly while you blow your whistle. If that's the case, when you are satisfied with your configuration you can consider gluing the mouthpiece into place.

Try the above in several different configurations to find the loudest whistle. If none of the above work, you can try the next two steps.

Cutting/sanding your fipple
--If you've tried the above, you can try sanding down the end cap a bit more, and adjusting a bit the sides of the cut barrel portion. If you can't blow the whistle at all, this is definitely the area you need to fix.

Cutting lip/hole larger
--If you've tried the other things, you can try cutting your angle differently on the lip.

Measure and cut the ink cartridge at 2 1/8 inches from the part which begins the straight portion. The ink doesn't generally come out, but if you leave it sitting somewhere on an angle, or touch the ends with your fingers, it can get a little messy.

Once you are happy with your whistle, you can turn it back into a mini-pen for storage. Slide the now-shortened ink cartridge back into the pen.

If desired, you should have enough room to also place the cap on the pen. Currently this takes up extra valuable space in the Altoids tin, but I will work on turning the cap into a small-game trapping mechanism to make it earn its place.

Consider adding instructions to the barrel of the mini-pen to explain about taking out the ink cartridge before use. Some pens will still work nicely with the ink cartridge in place, but most won't. In order to use the whistle you will need to remove the ink cartridge temporarily.

Now your whistle pen is complete and ready for your tins!