How to Pin
a Butterfly

Hey, I'm Chris

The whole process at a glance

What you'll need

These are the things you'll work with, and they all come in your EntomoBoxes butterfly kit. Each name links to the product if you ever need a refill.

Butterflies

Dried and folded in paper envelopes, unless you chose a kit without them.

Pinning board

Holds the body in a groove while the wings dry flat.

Pinning needle

Hooks a vein under the wing. This is what you spread with.

Entomology pins

Stainless steel pins that go through the thorax. One per butterfly.

Setting pins

Big-head pins that hold the foil in place without slipping.

Foil strips

Clear strips that press the wings flat without marking the scales.

Tweezers

Hold the body steady while you inject water and test if it's ready.

Syringe

Thin needle for injecting warm water into the thorax.

Dried butterflies arrive folded in a paper envelope with the wings closed. Before you can open them, the wing muscles need to soften, otherwise the wings crack. This is the single most important step of the whole process.

1. Fill the syringe with warm tap water. Warm, not hot.
2. Take the butterfly out of the envelope and place it on a flat, stable surface.
3. Hold it gently but firmly with your fingers or tweezers, so it can't move.
4. Insert the needle into the thorax, the middle part of the body where all four wings attach. The easiest entry point is right where the abdomen meets the thorax (Fig. 1, 2). Never inject into the abdomen (it tears) or the head.

1. Inject the water slowly until a droplet appears at the puncture or starts dripping out. That tells you the thorax is full.
2. Pull the needle out and place the butterfly on the upside-down lid of the container (Fig. 3).
3. Spray the inside of the container until all walls are covered with fine droplets (Fig. 4).
4. Turn the container over the lid and close it, so the butterfly sits inside the humid chamber (Fig. 5).
5. Wait at least 24 hours. Large butterflies and specimens stored for years need 36-48 hours.

Is it ready? The squeeze test

Take the butterfly out and gently squeeze the thorax with tweezers just below the wing joints. If the wings swing open easily, it's ready.

If they resist even a little, don't force them, they will snap. Inject a bit more warm water, put it back in the chamber and check again in 1-2 hours.

Two details decide whether your finished specimen looks professional: a perfectly straight pin and the right height on the board. Take your time here.

1. While gently squeezing the body with tweezers (the wings open slightly, which makes it easier), push an entomology pin straight down through the center of the thorax (Fig. 7, 8).
2. The pin must stand at exactly 90 degrees to the body (Fig. 9, 10). Even a small tilt makes the butterfly dry crooked.

1. Hold the pin at the top and lower the butterfly into the groove of the pinning board. Keep it centered, with the pin straight in both directions (Fig. 11).

1. Push the pin in until the wing joints sit exactly level with the surface of the board panels (Fig. 12). Too high and the wings angle upward, too low and they hang into the groove. This one detail makes a huge difference in the final look (Fig. 13).

This is the part that takes practice. The whole trick is the foil: when you pull it toward you, it gently presses the wings flat. Once you get the feel for it, everything else falls into place.

1. Cut two strips of pinning foil, each at least twice as long as the longest wing. Beginners, go even longer, it gives you more to hold.
2. Lay one strip across one side of the board and pin it at the top with two setting pins (Fig. 14). Let it overhang the edge a little, you'll need that later for the antennae.
3. Keep the strip straight and parallel with the edge of the board panel (Fig. 15).

1. Slide both the forewing and the hindwing under the foil. Then pull the free end of the foil toward you against the board. Notice how it presses the wings down (Fig. 16).

Practice this pull-and-press motion a few times before you start moving the wings. It's the foundation of everything that follows.

1. Lift the forewing up into position with the pinning needle. Slide the tip under the wing, hook the thick vein near the front edge (Fig. 17) and push the wing up (Fig. 18). As you move it, keep pulling the foil down with your other hand so it holds the wing as you go.

1. Once the forewing is in place, secure it with four setting pins placed in the foil around the wing, never through the wing itself (Fig. 20).
2. Now the hindwing. Move it up so it slides under the forewing, then secure it with another four pins (Fig. 21). You can do this two ways. Slide the needle underneath and push the wing up from below, the same as with the forewing. Or place the needle tip on top of a thick vein near the base of the hindwing and very carefully push the wing up from above (Fig. 22). Only ever press on a strong vein, never on the thin membrane between the veins, or it will tear. Neither way is easier or better, so try both and see what suits you. After years of pinning I still use both, depending on the butterfly.

Hindwing ended up on top?

No stress. Secure the forewing first, then use two pinning needles: one lifts the rear edge of the forewing, the other slides the hindwing underneath.

Needle catching the wing?

If you pierce a wing because the needle is too sharp, blunt the tip a little on fine sandpaper. It will slide along the veins much more gently.

1. Flip the board upside down and repeat on the other side. This way your hands are in exactly the same position as before. Left-handed? Same trick, just mirrored.
2. When both sides are done, remove the two pins that held the foil at the start. Tuck the antennae under the foil and guide each one into a natural forward position with a pin next to it (Fig. 23, 24).
3. Support the abdomen with two pins crossed in an X on either side, so it doesn't droop while drying (Fig. 25).

Ran out of foil?

When your foil strips run out, grab a refill, or try pergamen tape, which works great on butterflies too.

One more time, on a second butterfly

Here is the whole spreading part again on a Charaxes, so you can see the same moves on a different shape of wing.

The specimen now needs to dry completely before it comes off the board. Taking it off too early is one of the most common beginner mistakes, so be patient.

Is it dry?

Touch the abdomen lightly with a pin tip. It must feel completely rigid with zero give, and the wings should be stiff. Any softness left? Give it another 3-5 days and test again.

Taking it off the board

1. Remove the setting pins and peel the foil back slowly, from the outer edge toward the body. Press the foil down with your other hand while pulling each pin out.
2. Hold the entomology pin (never the wings) and lift the butterfly gently off the board.
3. Place it into your display frame (the Premium kit comes with one). Frames with a foam back let you position the pin exactly where you want it. For permanent displays, I use a hot glue gun.
4. Broken antenna or a small tear? Fix it with insect glue once the specimen is dry.

Protecting your collection

A collection is only as good as the box you keep it in. Use good quality boxes that close tightly to keep pests out, and keep some kind of pest deterrent inside at all times. I use moth papers with transfluthrin. For wall frames, you can seal the edges with silicone.

Keep everything away from direct sunlight and windows. Store collection boxes in a dark, dry place like a closet.

Common mistakes and pro tips

FAQ