Big Pipe Flashlight




A waterproof sealed beam flashlight made from 4" plastic drain pipe and fittings.

Why sealed beam? Old school is the answer!
It's a lamp with a really tight beam.  Forms a clean spot that throws a super far distance, but doesn't draw a lot of power.  With the 6V lantern battery, it would  give 12+ hours of usable light.  As a spotlight.
The US Navy likes that lamp.  Look up Navy Battle Lantern!

Step 1: Things You Will Need

1. About a foot of 4" plastic DWV pipe.  A 9" piece will be the flashlight body and 2 half inch long pieces will be rings to hold the lens guard.
2. A PVC 4"x4" hub.
3. Sealed beam lamp #4546. Still made and sold online.
4. A 6V lantern battery.  About $8.50 at Lowes.  They have cheaper ones, but the Duracell is alkaline and is made in the USA!
5. A round piece of clear plastic, 4 1/2" in diameter. For the lens guard.
6. Silicone caulk.
7. A screen door handle with button.
8. A pushbutton switch.
9. Screws to hold on the screen door handle, and 2 1 1/2" long 1/4" sheet metal screws of lag screws. To hold the battery.
10. Wire - about 2 feet of #20 wire.
11. 2 feet of screen window spline.
12. A PVC 4" test cap. Forms the back of the flashlight.

Step 2: Body of the Flashlight

The PVC pipe is the body. It should be about 9" long.
Starting with a longer piece of pipe, cut 2     1/2"   wide 'rings' from it.  These will be used for the lens guard in step 7.  Then cut off enough to make the flashlight body 9" long.

Next, drill holes in it to mount the screen door handle and the switch.
The  2 small holes are for the handle and the larger hole is for the pushbutton switch.

The button on the screen door handle will turn on the light!

Step 3: Make the Switch Waterproof.

Before installing the switch, put a finger from a rubber glove over it.
When the switch is tightened down, the rubber will keep out water.

Step 4: Mount the Switch.

A nut on the inside secures the switch.  Funny looking, eh?

Step 5: Mount the Handle.

2 screws from inside the pipe will secure the handle.  A short screwdriver really helps! 
I put caulk around the holes before I put the handle in to keep things waterproof. 
Here you can also see the yellow rubber glove end from the inside.

Step 6: Set Up the Shock Proofing for the Lamp.

At the top of the pipe and the inside of the 4"x4" hub, hot glue in a rubber ring.  Here I used spline from a window screen.  This just is to protect that glass sealed beam lamp. 

Step 7: Make the Lens Guard.

On the left is the 4"x4" hub. Next is a narrow ring of 4" pipe, a round piece of clear plastic and another ring of pipe.  I used a miter box saw to cut the rings of pipe.  Use care with a power miter box, because pieces of plastic can go flying.  Using a hand miter box  was better!
I cut out the clear plastic with a jig saw.

These pieces get caulked around the edges and pushed into the hub as  far as possible.

Step 8: Wire Up the Sealed Beam Lamp.

One of the wires from the switch goes to it and the other should go all the way through the pipe. This will go to the battery.

Step 9: Put the Business End Together.

Place the lamp on the top of the pipe and push the hub over it.
Caulk it first.  You could use solvent weld glue, but then it could never come apart, and the lamp couldn't be replaced.

Step 10: Make the Battery Holder.

I needed a quick way of holding the battery and this is what I came up with.
Put 2 3/16" holes in the pipe, right where you want the battery (about 2 1/2" from the open end of the pipe).  Put two  1 1/2" long  quarter inch sheet metal screws into the holes. After the battery is in, tighten the screws down.  They will push against the battery and hold it.

Step 11: Wire Up the Battery.

Attach the other wire from the switch and the wire that went all the way through the pipe from the lamp to the battery.
A screw terminal battery is better, but hard to find. You can use a spring terminal battery, but then you have to put screws and washers through the terminals.  Heck, soldering might be easier!

Step 12: Finish 'er Up!

Put the battery in and tighten down the screws to hold it.  I wrapped the battery in rubber so that it would hold better.

Put caulk around the open end of the pipe. Then push on the 4" test cap.

Step 13: The Final Product.

A tough, waterproof sealed beam light.
That 6V battery will store for a long time. I have an alkaline one that still works after  being used occasionally for 10 years!
The sealed beam lamp uses little power, but has a great throw.

This thing would be great on a boat!



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    4 Discussions

    Awesome project, been thinking about making a smaller LED one in the same fashion, looks like you beat me to the punch. oh well, I'll make it anyways.


    9 years ago on Introduction

    Great instructable!  Very clever use of the screen door handle -- I would have never thought of that!