Cold War Dead Drop Bolt




Introduction: Cold War Dead Drop Bolt

I saw one of these in the spy museum in DC and thought it was pretty awesome. 
Recently, I discovered you can buy these, and the commercial version probably holds
alot more then mine, but it is fun to make your own cold war spy gear.

This might not work very well if you carry it around in your briefcase or something,
but in the proper place the bolt is probably one of the best hiding places ever.

You only need a few things for this 
  1. Two bolts, one big one small
  2. Hack saw 
  3. Drill Press
  4. Tap and Die set
  5. High strength putty epoxy (PC7 works great).

It would be really cool if someone with more know how then I would make one of these that was a flash drive.

Step 1: Remove the Head

With your hack saw remove the heads of both bolts.
Try to make the cuts as smooth as possible.

Use a file on the large bolt so the head and the shaft can be put back together flush.
This is not necessary on the small bolt.

Step 2: Find the Center

Find the Center of the head and the shaft.
Use a punch to score the spot to help the drill bit
bite in the right spot.

Step 3: Identify the Correct Drill Bit and Drill

There should be a thread sizer in your tap and die set,
use this on the small bolt to determine the correct tap to use.
on the tap it should tell you what size hole to drill.

Once the correct bit size is determined drill your hole into the shaft.
  1. Set your depth, you don't what to drill all the way through.
  2. Secure the shaft.
  3. Go slowly and use thread cutting oil, it really helps.

Step 4: Tap the Shaft

Screw the tap in to the hole, use thread cutting oil, and only go a little bit at a time.
Screw it in then screw it out, little bits at a time.

Use the little bolt to check if you have gone far enough.
It only need to go in far enough to hold good.

Step 5: Drill Head

Drill a hole in the head of the bolt, a little bit bigger then the shaft of the small bolt.
You want there to be enough room for the epoxy but it needs to be hidden by shaft of the big bolt.

Note: if both your holes were not quite in the center that is ok, it can be fixed in the epoxy stage.

Step 6: Epoxy

It's time to epoxy the small shaft into the head of the big bolt.
To stop it from glueing together take some wax paper cut a small X in it,
lay it over the hole in the shaft and screw the little shaft through the paper.

Mix up some PC 7 epoxy,( this stuff works great), and put in the hole in head.
Put it all together, if your holes were not quite in the center rotate both pieces
until it lines up right. Isn't it cool that it does that?

Let it sit for at least 3 days. The can says it cures in 12 to 24 hours but i messed with
mine too soon and had to drill out the hole again, so be patient. 

And that's that, you have a cool piece of cold war spy gear.

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    Reply 10 years ago on Step 6

    Any hardware store that sells epoxy should have it.
    i got mine at Ace.


    10 years ago on Introduction

    Now all we need is some secret messages to pass back and forth. Someone to tell us how to produce microdots could be good.


    11 years ago on Introduction

    not sure how practical a usb hide-a-bolt would be.

    Possibly for micro-sd cards, but the narrowest usb drive I have measures just over .552 inches. to fit that, you'd need to start with around 3/4" bolt. I dunno about you, but that would look pretty conspicuous lying around any office computer I can think of.


    Reply 11 years ago on Introduction

    Well, i was doing some pre-summer cleaning of my harddrive, and cam across THIS image.

    Sadly, my comments/reply feature seems pretty buggy at the moment, otherwise i'd have put the image directly into the comment. :-(

    This method DOES require a bottoming tap(or fancy lathe skills) but produces a most pleasant result. As an added benefit, it allows you to have a cavity up to 95% the base diameter of the threads(if you're very careful drilling/boring)

    That SHOULD allow ytou to stash a thumbdrive(minus it's case) in any 3/4" bolt.
    A 5/8ths bolt with a long enough shank(thicker, non-threaded portion) should also work just fine.

    black hole
    black hole

    11 years ago on Introduction

    This is great! I'm going to vote for you. I've seen one that's made out of a hollow D cell battery with a smaller battery inside to provide power, while still leaving enough room for a message. The bottom was unscrewed with a magnet. I like yours better, though. Well done!


    11 years ago on Introduction

    I love stuff like this. Great idea. I have no idea what I would ever hide in it though.