# How to Make a Viking Sun Compass!

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## Introduction: How to Make a Viking Sun Compass!

Even though vikings were great at navigating the sea, even they got lost trying to find North while at sea. When they did, they made a compass using just a block of wood, a nail, a pencil, and the sun! You too can channel your inner viking, by making a Sun Compass! The compass will only last for a few days, since the earth is constantly moving around the sun, and changing its position, causing the shadow to now be in a new orientation. By using a bigger piece of wood, you can create a compass that works everyday, by marking it weekly.

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## Step 1: Material Gathering

To make this properly, you will need the following:

A 1X5 piece of wood (it should be a decent thickness)
The sun
A ruler/tape measure
A hammer
A nail
A pencil
2 large planks of wood
A wall anchor
And a saw horse

Find the halfway point on the board, and place an X mark at the back of the board. To measure out the midpoint, place the ruler or tape measure at one end of the board. Then measure the length of the board, and divide it by 2. You now know the midpoint between the two ends. Just measure to that distance, and make an X. Place the two planks of wood on the saw horse. Once marked, place your 1X5 block of wood on top of the wood planks.

## Step 3: STOP! Hammer Time!

After marking the midpoint at the back of the board, place a nail on the mark, and hold it steady. Then take the hammer and slowly beat it in. Once the nail is all the way through, be careful when taking it off, or you could get a nasty prick. Make sure it is a new nail, and not rusty, just in case you touch and cut yourself. Vikings didn't have tetnis shots! (MAY NEED ADULT HELP!)

## Step 4: It's Always Sunny In... My Yard

Once the nail is securely in, find a sunny spot that is out of the way of people walking, such as your front yard or backyard. Once you find the spot, place the saw horse down there, and place the wood with the nail in it on top, with the nail pointing up. Make sure the flat so the piece of wood can't fall off, and is laying flat.

## Step 5: Patience Is a Virtue...

Now that the main part is built, it is time to mark off spots on the board to help find north. Every half an hour, put an X at the end of the shadow of the nail. Repeat this every half an hour, or hour at latest, until you have marked from one end of the board to the other. This will vary, depending on the time of year. If you are making this for your kid, you may want to put something to cover the nail, like a cork. I used a wall anchor, since I had one lying around.

## Step 6: The Gnomon Curve... No, Not the Mythical Creature!

Once you finished marking all the spots on the board, measure each one to figure out which is the closest. Once you find which one is the closest, draw an hour to it. This is called a gnomon curve. On mine, the closest point, was the 7th mark. It will vary for all cases.

## Step 7: How to Use It

To use it, hold it level outside in the sun. To find north, rotate the board until the shadow falls on the gnomon curve. Once it hits it, you will know where north is!

## Step 8: HAVE FUN!

With your compass in tow, and your viking crew in tail, lead them north to plunder, pillage, and have fun... At least for the first few days...

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## 6 Discussions

Does this require a whole day's sun? The other trick is to put a stick in the ground, mark the shadow of the tip now and 15 to 30 minutes later. By drawing a line back THROUGH the stick FROM the points, it will point north.

I'm kind of confused...the orientation of the board has to remain fixed for the compass to work, right? If you mark the shortest distance then move the board's orientation, it does not seem it would work. If a ship were "spinning" at sea, would this still work without recreating the whole arc? (These are intended to be good natured questions, so please take them in the spirit they are meant...)

Paulie

I bet it does. I chose to make one for my Physics and Engineering class! We had to find an Instructable of what we wanted to build, and then make our own! We also read your tip guide on how to write an Instructablem, which was really helpful! :D

How do you ensure that the gnomon is vertical when you point the sun? If it tilts, the measure could send you to other part of the world, not where you want go.

No big deal. The shortest shadow of everything indicate the true North. Better than compass.