C47

C47

noun | Production

Film and television crew slang for an ordinary wooden spring clothespin - the type used for hanging laundry on a washing line. On a film set, C47s are used as a universal low-tech fastener: attaching color correction gels and diffusion materials to the barn doors and frames of lighting fixtures, securing cables, holding items in place, marking positions, and dozens of other improvised applications. The C47 is one of the most used items in the grip and electric departments' expendables kit and is typically carried in large quantities in every lighting truck.

Quick Reference

The Explanation: How & Why

The clothespin is one of film production's most useful tools precisely because it is cheap, widely available, heat-resistant enough to handle lighting gels, easy to apply and remove with one hand, and strong enough to hold lightweight materials in place against gravity and air movement. No purpose-designed alternative has displaced it because nothing works better for its specific application.

Lighting fixtures have adjustable metal flaps called barn doors that control the spread and direction of the light output. When a gaffer needs to add a color correction gel (CTB, CTO, CTS) or a diffusion material to a fixture, the simplest method is to clip the gel or diffusion to the barn door using C47s. The spring clip of the clothespin grips the edge of the barn door on one side and the edge of the gel or diffusion on the other, holding the material firmly. The wooden construction provides sufficient heat resistance for gels on most tungsten and HMI fixtures - it will char and eventually burn at very high temperatures, but for typical fixture use it is durable enough. Plastic clothespins would melt; metal ones would conduct heat and burn fingers. Wood is the correct material for this application.

The electric department typically carries hundreds of C47s in their expendables kit. On a day with many lighting setups involving gels and diffusion - an interior location with multiple sources being color-corrected - a single gaffer might use 30 to 50 C47s over the course of the day. They are cheap enough that they are never rationed. Running out of C47s on set would be an embarrassing logistical failure. For the folklore behind the name, see the USC Digital Folklore Archives entry on C47.

Historical Context & Origin

The clothespin has been used in film production since at least the sound era. Any production using gel on a lighting fixture faced the practical problem of how to attach it, and the spring clothespin was the simplest available solution. The "C47" designation appears to have emerged through the studio system as a way of assigning a professional catalog designation to an item purchased from domestic supply sources.

The origin of the name is one of film industry folklore's most entertaining stories, with multiple competing accounts. The most widely circulated version, documented in the USC Digital Folklore Archives, holds that studio executives auditing equipment requests would reject orders for "clothespins" as a mundane domestic item. Crews renamed them "C47" to sound technical and important, and the orders were approved. Another account, reported by Scouting NY, suggests the name came from the Douglas C-47 Skytrain, the versatile WWII military transport plane - returning servicemen working in Hollywood compared the clothespin's versatility to the plane's. A third theory claims C47 was a catalog number or bin number at a particular studio. A fourth suggests the IRS would not accept "clothespins" as a work-related expense but had no problem with "C47s."

Whatever the origin, the name is universal on English-language film productions. Ordering "a box of C47s" is as standard a professional request as ordering gaffer tape. In the UK and Australia, "pegs" is the more common term, though "C47" is widely understood.

How It's Used in Practice

Scenario 1 - Attaching Gel (Best Boy Electric / Gaffer): The gaffer asks for full CTB on the 2K fresnel in the background. The best boy cuts a piece of CTB gel to fit the barn door and clips it to the top and bottom of the barn door using two C47s. The gel is secure, flat against the barn door, and the fixture can be aimed and adjusted without the gel falling off. Setup time: 45 seconds. The best boy carries 50 C47s clipped to his belt for quick access throughout the day.

Scenario 2 - Diffusion Attachment (Gaffer): A large bounce card with a diffusion frame is being set up in front of a 4-foot HMI. The diffusion material needs to be attached to the frame without wrinkles. The gaffer clips the diffusion to the frame's edges using 6 C47s at even intervals, ensuring it sits flat and taut. No purpose-built system would be faster or simpler. Total cost of the fastening system: approximately $0.18.

Scenario 3 - Improvised Use (Grip): During a shot, a small prop - a piece of paper - keeps moving in the air conditioning draft from the set's ventilation. A grip reaches into their pocket, where they always carry a handful of C47s, and clips the paper's corner to the table surface. Problem solved in 10 seconds with a clothespeg.

Usage Examples in Sentences

"Give me two C47s on that CTB - it is starting to fall off the barn door."

"Box of C47s on the electric truck, left door, lower shelf. We need them on the set now."

"It is a clothespin. It costs three cents. It is the most useful thing in the kit."

"The first time you work on a real set and somebody asks you for a C47, and you know it is a clothespin - that is how you know you are in the industry."

Common Confusions & Misuse

C47 vs. Alligator Clip: An alligator clip (or crocodile clip) is a metal serrated spring clip used in electronics and sometimes on sets for specific applications. It is not a C47. The C47 is specifically a wooden spring clothespin. Alligator clips are used on electrical connections and for specific rigging applications. C47s are used for attaching soft materials (gels, diffusion) to fixture hardware. The materials matter: metal alligator clips conduct heat and can burn fingers when attached to hot fixtures; wooden C47s do not.

C47 vs. Gaffer Tape: Both are used to attach materials to set and fixture hardware, but through different mechanisms. Gaffer tape uses adhesive and leaves residue on surfaces it is applied to and removed from. A C47 uses mechanical spring pressure and is completely non-destructive. Gels are typically clipped with C47s rather than taped because tape leaves adhesive residue on fixture barn doors and gel material, which degrades the gel and creates cleanup work at wrap.

C47 vs. Sash Cord Clamp: A sash cord clamp is a heavier-duty spring clamp with rubber tips, used for securing larger items like flags, diffusion frames, or foam board to C-stands. C47s are for lightweight materials only - gels, diffusion, paper, thin fabric. Using a C47 for a load beyond its grip strength will result in the item falling, potentially damaging equipment or injuring crew.

Variations by Context

Key People & Films

The C47's origin story is rooted in the studio system of early Hollywood, where gaffers and best boys reportedly renamed clothespins to get them past cost-conscious studio executives. The USC Digital Folklore Archives documents this as occupational folklore shared among film students and crew members as a rite of passage - the first time someone asks you for a C47 and you know what it means, you are "in the industry." The term appears in virtually every film production made in the English-speaking world, from student shorts to studio blockbusters. The Scouting NY film jargon column cataloged the multiple origin theories, noting that the term may also relate to the Douglas C-47 Skytrain, the WWII transport plane known for its versatility.

Equipment / Tools Reference

Standard wooden spring clothespins are the C47 used on professional sets, approximately 3 inches long with a steel spring. Available in bulk from hardware stores, Amazon, or film supply houses like Filmtools for approximately $10-15 for a box of 100. Spring clamp alternatives (for heavier loads) include 2-inch and 4-inch spring clamps from Matthews Studio Equipment or Impact, which provide stronger grip for securing foam board, flags, or diffusion frames to C-stands. High-temperature C47s (wooden pegs without metal springs) are available for use on very hot fixtures where standard C47s would char. Binder clips from office supply stores serve as a metal alternative when wooden C47s are insufficient, though they conduct heat and must be handled with gloves on hot fixtures.

Standards & Specifications

No formal SMPTE, ISO, or guild standard governs C47 specifications. The C47 is a consumer product repurposed as professional film equipment. Standard wooden spring clothespins are approximately 3 inches (76mm) in length with a steel spring mechanism. The wood is typically birch or maple. Color is natural wood or white. No specific load rating exists, as the clothespin is designed for hanging laundry, not rigging equipment. The IATSE Local 728 training curriculum mentions C47s as part of expendables training for electric department certification, covering proper gel attachment technique and heat safety.

Common Questions / FAQ

Q: Why are they called C47s and not clothespins?

A: The most widely accepted story is that studio executives would reject budget line items for "clothespins" as a mundane domestic purchase. Crews renamed them "C47" to sound technical and get them approved. Alternative theories include a WWII Douglas C-47 Skytrain connection, a catalog or bin number, or an IRS tax classification workaround. The true origin is unconfirmed, but the name is universal on English-language film sets.

Q: Can you use plastic clothespins instead of wooden ones?

A: No. Plastic clothespins will melt when attached to hot lighting fixtures, especially tungsten lights that reach several hundred degrees. Metal clothespins will conduct heat and burn your fingers. Wooden clothespins are the correct material because wood is a poor heat conductor and will not melt, though they will eventually char at very high temperatures. Standard wooden spring clothespins from any hardware store are the correct item.

Q: How many C47s should a lighting kit carry?

A: The electric department typically carries 200 to 500 C47s in the expendables kit. On a day with heavy gel and diffusion use - an interior with multiple sources being color-corrected - a single gaffer might use 30 to 50 C47s. They cost approximately $0.03 each, so there is no reason to ration them. Running out is a logistical failure that stops the shoot.

Related Terms

• Expendables - The category of consumable supplies that includes C47s; they are one of the most-used items in the expendables kit
• Gel - The primary material that C47s are used to attach to lighting fixtures
• Diffusion - Another material attached to fixtures using C47s; frost, silk, and diffusion gel all use C47 attachment
• Gaffer - The lighting department head who most frequently uses and requests C47s on set
• Grip - The department that also carries C47s for their own rigging and attachment applications
• C-Stand - The rigging hardware from which C47-attached gels and diffusion are often positioned

See Also / Tools

The Shot List Generator is indirectly relevant - each lighting setup on the shot list that involves gels or diffusion on fixtures requires C47s. A detailed shot list showing the number of lit setups allows the electric department to estimate C47 consumption for the production day. For the stands that hold the fixtures and accessories that C47s attach to, see the C-Stand glossary entry.