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How do I make a pinhole? By Tom Lindsay
There are several ways to make a pinhole, and as many camps on which way is the best. I'm going to tell you how I make them, and I believe that it is the easiest way to make a pinhole.
Materials needed to make a pinhole
1. A 1"-11/4" square piece of .003 brass shim stock (just like heavy aluminum foil, but brass)
2. A new unsharpened #2 pencil with an eraser tip.
3. A #10 sewing needle
4. A 5" square or larger piece of scrap cardboard
5. A small piece of 400 grit emery paper
6. A pair of needle nosed pliers (optional)
7. A needle grabber (optional) you will find this at a sewing store.
8. A 8x loupe or good magnifying glass
Let's Do it!!!
The first thing that has to be done is to insert the needle into the eraser-tip of your #2 pencil. Get out the scrap of 5" cardboard. Put it on a firm surface (the table or floor will do fine). Now grab the #2 pencil and hold the pencil vertical (straight up and down) in one hand, and hold the #10 sewing needle vertical with your other hand. Center the needle on the eraser-tip end (eye end of the needle towards the eraser) and then with a downward push (using the cardboard for a place to push the sharp part of the needle into) get the needle started into the eraser tip. You might have to try a few times before you get it to look like example #1.
Example 1Example 2 Example 3
But it is worth getting it as straight as possible. Pull the needle back out of the eraser and start again only if you have to!!! When you are satisfied that you have it started straight, use the needle nose pliers or "needle grabber" to sink it in as far as it will go into the eraser tip.
Get out the .003 brass shim stock and lay it on the cardboard (find a fresh spot on the cardboard). Start twirling the pencil-needle tool (from now on just called the needle), like you see in example #2.
Make sure you are in the center of the brass shim stock square. Important note: The cardboard is not seen in the drawings, just imagine that it is under the brass shim stock). You will start to go through the brass shim stock as you twirl and push downward ever so slightly in a drilling motion. You can now see the needle coming through the brass shim stock as in example #3.
Pull the needle back out and you will see that you now have small burrs on the opposite side that you started from. See example #4.
These burrs are what you will now need the 400 grit emery paper for. Sand the brass shim stock on the burred side going in a gentle circular motion with your emery paper until the burrs are gone (don't over do this step).
Now you want to flip the brass shim stock over to the opposite side (the side that you just sanded the burrs off of). Insert the needle into the hole and repeat the twirling motion as shown in example #5.
Example 4 Example 5 Example 6
This time you will get very little burrs on the opposite side that will look similar to those in example #4, but not as pronounced. Sand these burrs off the same way as you did earlier being ever so gentle. When you are satisfied that you have removed those burrs , stick the needle back into the hole (from the opposite side of the brass shim stock) and then CAREFULLY twirl the whole square piece of brass shim stock as shown in example #6.
It should twirl pretty easily and yet still be snug. When you have gotten to this point you may or may not have to sand some more ultra small burrs if they do show themselves on the opposite side from where you last inserted the needle. If need be, sand them!
At this point all you need to do is get out the loupe or magnifying glass and check to see if you have a nice CLEAN pinhole. If you do you are finished. If not repeat inserting the needle into the hole on the opposite side of the brass shim stock and give it another good twirl like in example #6, until you do see a good clean pinhole!!!
Congratulations you now have a pinhole and know how to make one too, way to go!!!
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