Chickadee Birdhouse

# Black-Capped Chickadee Birdhouse — Printable Two-Piece Design

A dimensionally accurate birdhouse sized specifically for black-capped chickadees (*Poecile atricapillus*), based on Cornell Lab of Ornithology and North American Bluebird Society guidelines. Prints in two separate pieces — a floor-down box and a peak-up roof — that lock together via integrated tabs.

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## Features

**Box** - 101 × 101 mm interior floor, 220 mm interior height - 28 mm entrance hole centered on the front wall, 175 mm above the floor (~6.9 inches) — deep enough to deter predators, right in the recommended range for chickadees - 27 horizontal climbing grooves on the inside of the front wall below the entrance hole, so fledglings can grip and scramble out - 4 × 6 mm drainage holes near the floor corners - 2 × ventilation slots (15 × 5 mm) near the top of each side wall - Keyhole-style mounting slot (8 × 30 mm) centered on the back panel, 20 mm from the top — slides over a screw head for tool-free installation - Two roof-attachment tabs on the top of the front and back walls

**Roof** - 121 × 121 mm footprint — 10 mm overhang on all four sides - Pitched ridge running front-to-back, 35 mm above the roofline - Two slots (with 0.3 mm clearance) that press-fit over the box tabs to hold the roof securely without glue or hardware

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## Print Settings

| Setting | Recommendation | |---|---| | Material | PETG (best balance of ease and weather resistance) or ASA (best outdoors) | | Layer height | 0.2 mm | | Walls | 3–4 | | Infill | 15–20%, gyroid or honeycomb | | Supports | Not required — bridging handles the entrance hole cleanly | | Bridge speed | 20–25 mm/s |

**Plate 1 — Box:** Print floor-down. No supports needed with standard bridging settings enabled.

**Plate 2 — Roof:** Print peak-up (flat ceiling face on the bed). The sloped faces print cleanly at this orientation.

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## Assembly & Mounting

1. Press the roof onto the box — the tabs click into the roof slots and hold it in place. No glue needed; the friction fit is intentional so the roof can be removed for cleaning between seasons. 2. Mount to a post or tree using a single screw through the back-panel keyhole slot. Recommended height: 4–6 feet off the ground, facing away from prevailing winds. 3. No perch peg — chickadees don't need one, and a perch actually helps predators. Leave it as-is.

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## Notes

- Interior dimensions and entrance hole size follow published guidelines for black-capped chickadees. Do not scale the model — scaling will change the entrance diameter and may attract or exclude the wrong species. - Chickadees prefer boxes placed near woodland edges with some shade. They'll fill the cavity with moss, plant fibre, and fur. - Clean the box out each autumn after the season ends to prevent parasites and give the birds a fresh start in spring.