Tie Your Spire Down

Rigging Camden Spire

Rigging Camden Spire

Last Thursday, I popped out of bed at 4 am, like Sal on her way to Bucks Harbor. Scott informed me that if I wanted to help remove the Chestnut St Church spire in Camden, I needed to be there by 6:00. By the time I arrived, Scott and Arron had set the rigging. About a third of the way up the spire, eight laminated KD 2x10s poked through the spire like an avocado pit ready to sprout. PTF was hired to direct the spire removal and design a timber-framed transition from the old belfry frame to the new fiberglass spire. We’d worked with the G.C. before on True-Randall farm, Taylor-made Builders are good folks who do high-quality work; so even though fiberglass replacements are not our thing, we got over ourselves because Taylor and his crew are such a pleasure.

IMG_7233This steeple is so tall that a 120′ man-lift couldn’t reach the weathervane on the day we went up there to remove the weathervane (oops). The main church is two full-height stories. Starting just below the main ridge-line, the belfry posts rise 30′ to a plate level just below the clock dials. The original spire rafters penetrate into the belfry, landing on a girt 5′ below the plates. The spire rafters pass through the dial level, behind four 6′ diameter glass dials.  Above the dials, the original spire rafters were severed and sistered with relatively light, laminated 2x4s. That repair was performed in the 1990s by a talented and eager Eagle Scout. This go-round, we designed a timber-framed “lantern” that crosses the belfry plates like a crab. Eight 8×8 posts rest upon the lower crab and support a maintenance floor behind the clock faces. The upper lantern plates, or upper crab, extends well into the fiberglass spire, 6′ above the horizon of the clock faces. Four new fiberglass dial hoods will protect the dials, and be structurally fused to the new fiberglass spire. The lantern frame we’re cutting reproduces the telescoped framing levels found in this building and other historic steeples.

Lantern Iso, X-Ray

Lantern Iso, X-Ray

The model we’d created for the lantern design allowed us to accurately calculate the height at which the rigging would need to be placed in order for the spire to be slightly bottom-heavy as it flew. In fact, once prone in the driveway, the spire balanced like a seesaw on the fulcrum of its rigging. A top-heavy spire might flip mid-air, which would be just as dangerous and scary as it sounds.

Chestnut St Church, Crane, and Rigging

Chestnut St Church, Crane, and Rigging

We hung a cage from the main ball of the frame to protect the weathervane from the rigging straps. We linked together the crane operators’ longest cables and our longest rigging straps, to connect the four corners of the metal frame to our rigging beams. The last strap was doubled over, resulting in an eight point pick.

Spire cage

Spire cage

The crane flew the rigging up to the crew on the top of the staging, and we pulled the rigging straps away from the spire as the operator located the ball directly over the weathervane. The rigging was accessed by ladders off the staging, which was less efficient than it was photogenic.

Teamwork

Teamwork

Once the rigging was securely attached, we crawled inside the spire and used saw-zalls to cut first the spire sheathing, then the mast and then all eight rafters. In my experience, the penultimate step of severing the last connections is the most stressful and variable part of the entire crane day. As Arron warned the crew, a forgotten toe nail could prevent the spire from releasing safely and evenly. We were lucky to have a skillful crane operator from Keeley. We wanted the crane to take enough weight, and put enough tension on the rigging to prevent our sawzall blades from binding, but we did not want the spire to bounce or release with any energy.

Witch's hat with a crown of thorns

Witch’s hat with a crown of thorns

Scott and Arron checked in with the operators. When we started cutting the sheathing, the crane had 1500 lbs of weight on the ball. For the mast, 2500 lbs. As the last of the rafters were cut, the crane was taking 3500 lbs. Unfortunately for the spectators on the ground, a safe spire removal looks slow and boring. Unfortunately for my story, the spire released without any hitches. The spire weighed about 8800lbs, which reflects its light framing.

A Bittersweet Triumph

A Bittersweet Triumph

The crane operator lowered the spire safely to the street, and the crew cut the cone into sections small enough to carted away by a pulp truck. The Penobscot Bay Pilot got some beautifully boring drone footage of the removal, and covered the story, here. For more photos of our process, visit our Flickr album.

Spire got the drop on you

Spire got the drop on you

4 thoughts on “Tie Your Spire Down

  1. Pingback: Lickety Lantern Brasen Hill Barn | Preservation Timber Framing

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