Dead Drop Spike V.1




This is a project I made a little while ago as a birthday present for my friend Daniela who introduced me to geocaching. It is based on several designs I saw in a book on spy gadgets. They would have been used for passing stolen documents and film between an agent and their handler, storing money and documents as well as other tasks.

I've just completed an Instructable for version 2. It adds a locking lid and a D-ring to seal it.

Here's what you need to make your own:

• Pipe cutter (optional)
• Hacksaw
• Metal working lathe with cross slide
• Drill or drill press (optional)
• 1/4 inch drill bit
• Mill and 1/4 inch milling bit (optional)
• Countersink (optional)
• Needle nosed pliers
• 1/8 inch diameter nail
• Applicator (and mixing dish if using 2 part epoxy)

• 3/4 inch external diameter, 5/8 internal diameter, aluminum pipe, 3 1/2 inches long
• 3/4 inch internal diameter aluminum pipe, 1 1/8 inches long (The external diameter does not really matter. The piece I used was about 7/8.)
• Two sections of 3/4 inch diameter aluminum rod. One section 1 5/8 inches long, the other 1 1/8 inches long
• 8 inches of 1/16 of an inch diameter SS wire
• Epoxy intended for use with metal
• Strong string

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Step 1: The Sidewall and Point (the Body)

Cut the 3/4 inch external diameter pipe to length (3 1/2 inches). If you are using a pipe cutter be sure to round off the burr that is formed. This will make up the side wall of the spike.

On the lathe turn a 1/2 inch long section from the end of the 1 5/8 inches long section of 3/4 inch aluminum rod down to a 5/8 diameter.
On the lathe turn a point on the opposite end from the one you just turned down.

This piece will be the point.

These two parts make up the body.

Step 2: The Collar and Top (the Lid)

Cut a 1 1/8 inch long section of 3/4 inch internal diameter pipe. This piece will be the collar.

A. Take the 1 1/8 inches section of 3/4 inch rod and drill a 5/8 inch deep hole in one end.
B. (optional) Mill two 3/8 of an inch long, 1/4 inch wide, grooves on opposite sides of the undrilled end.
C. If you have milled the grooves, then drill a hole 1/4 of an inch from the end from one groove to the other. If you have not, then drill a 1/4 inch hole through the rod 1/4 of an inch from the undrilled end and countersink the holes. This piece will be the top.

These are two of the three parts that make up the lid.

Step 3: The Spindle

Bend the wire over the nail at a point as close to the center of the wire as possible. Trim the ends of the wire so that it is 3 1/2 inches long. This piece will be the spindle.

This is the third part of the lid.

Step 4: Gluing

Test fit all parts together as shown in the above image. Glue all parts together following the instructions for your epoxy.
It is easier to glue the spindle into the top before gluing the collar on.
At this point, you can put the lid in the lathe to round off the upper edge of the collar, however it is not necessary.
After the glue has dried, tie the string through the hole in the lid.

Step 5: You're Done

There are a few ways that you can wind paper onto the spindle. The spindle has space for a strip of paper up to 2 3/4 inches long. The way I have set it up is to make a small notebook out of waterproof paper. I think it would be slightly easier on the notebook if you thread it onto the spindle just past the staple,  however, if you are using it for geocaching and it will be handled by people who are unfamiliar with the spike, I would suggest threading the notebook around its middle as it is less likely for it to slip off when you are opening and closing the spike.

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    17 Discussions


    5 years ago

    fellow casher from CA/MT here nice instructable happy cashing geocashe user name AFriendlyJS


    Reply 7 years ago on Introduction

    as a cheap waterproof "paper" you can use tyvek that sometimes can be found on envelopes or in kite stores. mostly it is white and one side of the surface looks like old paper or leather.

    you can write on it and i saw printed symbols on it so once i tried to print on it with my old laserjet printer. the first attempt wasn't good - i printed on the surface side of the tyvek sheet, glued on a normal paper to make it more stiff. the result was the tyvek melted around the hot laser printing cylinder. fortunately i could pull the sheet away from the cylinder and the printer worked as it did before. in my second attempt i tried printing on the other side, being more flat, and it worked fine. the result was ok - if i didn't fold it too often the laser toner stayed stable enough on the tyvek - and it was water resistant!

    sure... you can buy waterproof paper somewhere but i wanted to try this material. for my purposes it worked well so if you have an old pinter around and you (or somebody else) wouldn't be ashamed of it being executed give it a try!


    Reply 7 years ago on Introduction

    You could also take a look at the instructable for printing a map on plastic, if you were interested in printing stuff/waterproofing.

    Tyvek, at least in big sheets (could be different but is still made by tyvek) comes in big huge rolls for water resistance when building a house, hardware and home improvement stores should sell it.


    7 years ago on Introduction

    I'm always interested in creating geocashing hides but these require a lathe which I do not have. Where can i find a way to make something similar without having to use a lathe? Maybe something like buying a piece of aluminum electrical conduit cutting off a suitable piece and hammering the end to a point.

    5 replies

    Reply 7 years ago on Introduction

    You could make the point by rolling a cone out of paper and taping it to one end of the pipe and then poring a small amount of resin in threw the other end so that it comes up to about 1/2 an inch from the bottom of the pipe. You could use a commercial end cap for the lid.


    Reply 7 years ago on Introduction

    Use PVC Pipe with the End caps.... glue one on and the other as a top that can be twisted and pulled off.. Even though it would be pretty much water proof if you also picked up a little tub of silicon grease in the plumbing dept that would pretty much water proof the cache... Cheap, easy to make and pretty much waterproof.


    Reply 7 years ago on Introduction

    For little jobs you can use a drill press instead of a lathe. Slow and gentle helps, and making up a tool rest from some scrap wood and clamps is suggested. Also remember that the raw material is not supported so don't press too hard.


    Reply 7 years ago on Introduction

    I've gotten by with just chucking a part into a hand-held cordless drill held in a vise. A file used to be called "a poor man's mill", and it works great for small jobs. I have access to a mill, and it's sometimes quicker to just clamp the part and grab a file than to do a real setup.


    Reply 7 years ago on Introduction

    This will be weaker but maybe you can use the spike from those cheap solar landscaping lights.


    7 years ago on Introduction

    why not just use old prescription plastic containers? if you want to spike it use a peg and tape............easy to make and cheap enough........Thanks for a great article..........................................John G


    7 years ago on Introduction

    Just wondering here maybe for version 2.0 why don't you use a metal cigar tube and machine a pointed tip on the end instead of a flat one that way you could make them cheap and fast if you had to.
    Just a simple thought I had!

    1 reply

    Reply 7 years ago on Introduction

    I don't know anyone who smokes cigars, but that sounds like a good idea. How thick are the side walls?