Build Your Own Geocache Waterproof Tube Container

GeoCaching is GREAT!   It's basically a high tech treasure hunt game growing in popularity the world over.  All you need is internet access, a GPS; Smart Phone, or even a map and compass, and of course, something to find. 
What Geocachers need to find is called a Geocache.  And creating a Cache to hide can be almost as addictive as the sport itself.
To learn more about Caching check out geocaching.com  and opencaching.com .
Another great resource dispensing indispensable news and geocaching trivia is a top notch Pod Cast at www.podcacher.com

I've designed this container be long enough to hold a pen, and generous sized cache log.
After searching around the Instructables.com site, I found several very good instructables of two bottle tops being bonded to create a much smaller container which would be know in the Caching world as a micro cache.
Here's a few versions that may suit your needs if this instructable isn't quite your flavor:

• Micro (Geocache) Container - by BrantFlakes315
• Bottle Cap Container - by etgainey
• Podcacher - How To Make A Micro Cache - by flapper501

And there's likely more to find if you look.

Though you may substitute some or all of the items and or tools with what works best for you, here is a list of what I used in the creation of this Instructable:

INGREDIENTS:

1. 3/4 INCH PVC TUBE
2. PEN
3. HACK SAW
4. PLASTIC POP OR WATER BOTTLES WITH SCREW ON CAPS x2
5. DREMEL OR OTHER ROTARY TYPE TOOL WITH SANDING DRUM ATTACHMENT
6. OSCULATING SANDER WITH SANDPAPER
7. PVC CEMENT
8. STANDARD PAPER SHEET x2
9. SCISSORS
10. STAPLER
11. SPRAY PAINT (VARIOUS CAMO) Shown in Intro Image

Use the pen you wish to place inside your container to roughly measure the length of your project.
Then mark a cut line directly on the tube..

Find a sturdy area to do your cutting and use hacksaw to cut through the tube as marked in previous step.
(I just braced it against my knee).

Use your hacksaw to cut the tops off your plastic water or pop bottles.
I found that lightly scoring the area to be cut, wile slowly rotating the bottle, made for a nice straight cut all around.
The second image shows the bottle top separated from the bottle.

OPTIONAL: IF YOU BOTTLE HAS A RIDGE DESIGNED FOR CARRYING,YOU MAY CHOOSE TO CUT ON EITHER SIDE OF THAT.  I DECIDED TO INCLUDE THE RIDGE IN CASE I WANTED TO USE FOR SECURING A STRING TO LATER IF I DECIDE TO HANG THIS CACHE FROM A TREE.

There may be some rough edges caused created during the cutting steps.  (my plastic bottle melted a bit from the friction created by the hack saw).
Try fitting the bottle top over the end of the PVC tube as shown in the first photo of this step.
If they will not fit snugly together use a sander (or hand sand)  to smooth the outer rim of the PVC tube.
I found that a Dremel with sanding drum attachment worked well on the inner rim of the PVC.

Next try using the Dremel with sanding attachment to remove the roughness from the inner rim of the cut bottle top.
Try fitting the PVC and Bottle tops together again.
Notice the tapered outer rim of the PVC in the second photo of this step.  I used the sander in an attempt to assist the PVC into a snug fit, but found using the Dremel again in the NEXT STEP proved to be a better solution.

Using the dremel proved to be a great time saver in this step. 
Rotating the PVC tube incrementally while attempting as best as possible to remove equal amounts of material all around, apply the Dremel sander attachment lightly, and check your fit with the cut bottle top often until a snug fit is obtained.
Do this for both ends of the PVC until you are satisfied with the results.

Using ABS or PVC cement, select a well ventilated work area and read all safety precautions and directions before proceeding.
If your choice of cement came with a dabber affixed to the inside of the lid, apply lightly to both the outer rim of the PVC tube area you've sanded, as well as to the inner neck of the cut bottle top.
Depending on your cement, and amount applied, it may dry quickly, so just work on one bottle top / PVC combination at a time.
Once both parts have cement applied, fit them together and apply some pressure while rotating approximately a quarter of a turn.
This will help both parts to bond better.
Once satisfied, repeat the process on the other bottle top / PVC set.
NOTE:   As a precaution, leave the screw on caps off their perspective bottle tops until the cement has dried and cured to avoid accidentally permanently affixing them to the bottle tops.  Cement should cure completely after several hours.

If your goal was to create a waterproof container to store small items, then you're done.  Congratulations!  Excellent job!

However, if you would like to continue with completing a ready to hide geocache container to impress your fellow Cachers, you'll need to include a Cache Log.

Take a couple pieces of paper and set your Cache container near one edge.
From here you will decide which length is best to fold in half to create a Log Sheet suitable for your container.
After making the fold, use a pair of scissors to cut along the fold.
Stack your resulting sheets of cut paper, then place a couple staples at one end, effectively creating a small booklet.

Now using the pen, you can hand draw horizontal numbered lines for geocachers to sign and date, marking their presence at your Cache.
Alternately, you could create a more refined Cache log on a computer and print before the cutting stage, download and print a log sheet online at Geocaching.com, or use lines paper and just add information you want displayed on your Log Sheet.

Once the log has been created, you might like to wrap it around the pen and insert the rolled package inside your new container, replacing the screw on bottle caps as shown in the last photo of this step.

Using spray paint which can be found in the sporting goods section of some retailers might be one option to consider for adding additional camouflage if required for your new geocache container.
I hung my container from a thread while making short brisk passes with various spray paints to obtain a nicely camouflage look. 
Maybe covering your container with glue and rolling it in fallen pine needles, dirt or sand might be another option (not shown here)
Be creative, and most of all, have fun.