The Rockpile

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04400/OLD The Rockpile

OLD WORLD STONE LTD. Fabricators of Dimensional Cut Stone

Packer Memorial Church, Inside this issue:

Lehigh University, Bethlehem, PA Cathedral Basilica of 2 the Immaculate Con- ception, Denver, CO

Tools of the Trade - 2 Field Dimensioning

Plant News 3 – Meet Kuka

Ask a Designer 3 - Geometric Tracery Windows

Upcoming Trade Shows & Conventions

Sealant, Waterproofing & Restoration Institute, 2019 Winter Technical Meeting Santa Monica, CA March 10-13, 2019 Six years and 175 tons of Wallace sandstone were used to complete the replace- Conference & Trade Show ment of 29 tracery windows at Packer Me- morial Chapel. The original sandstone was face-bedded and the ornate tracery was American Glass Guild / delaminating. Previous restoration efforts Stained Glass Association to patch and paint the windows had failed. of America Co-conference Our work to replicate the existing windows San Antonio, TX began in 2012, when most of our carved stonework was hand cut. It was labour in- May 30-June 5, 2019 tensive and time consuming. Gradually we Laurie Wells - Speaker implemented existing and added new CNC Stone Tracery Windows, technology to expedite the work, eliminate Old World Craftsmanship human fatigue, and reduce harmful dust. meets This one project exemplifies our techno- New World Technology logical progress and our evolution in the stone cutting trade. The last window will Conference & Trade Show be installed in the summer of 2019. Read 16 foot dia. Rose Window - photo by Montec Restoration more at www.oldworldstone.com.

Page 2 The Rockpile Cathedral Basilica of the Immaculate Conception, Denver, CO

In June of 1997 lightning struck the 210’ west spire of this French Gothic styled cathedral basilica. It required immediate attention to dismantle and rebuild the precariously hanging limestone. Old World Stone hand carved 120 crockets and ornate elements for the spire. Twenty years later we returned; carving replace- ment stone for both spires. This time we used 3-D scanning and robotic milling to get the job done. In total we replaced another 50 crockets. They key to mak- ing efficient use of the technology was having multiple, identical units to replicate. Skilled carvers finished each piece by hand. The recent project was man- aged and installed by Summit Sealants, Inc. of Montrose, CO.

In architecture, `tracery` is the stonework elements that support the glass in a Gothic window. The name probably derives from the 'tracing floors' on which the complex window patterns were laid out. The earliest type was plate tracery which began as openings that were pierced through a stone slab. Later, bar tracery evolved as Gothic architecture and changing features, like the thinning of walls and enlarging of windows developed. However, instead of a slab, the windows were defined by molded stone mullions which were lighter and allowed for more openings and intricate designs. Other notable styles of tracery to follow include geometrical tracery and curvilinear or flowing tracery. Tools of the Trade - Field Measuring Laser measuring tapes and 3-D scanners have changed the way we record site measure- ments. Gone are the days of cardboard templates, profile gauges, and traditional tape measures. Hand-held laser measurers use a light beam to measure lengths from point to point. They are quick, efficient, and accurate. We use them for overall dimensions of architectural openings and running lengths of band courses and cornices. Hand held scanners are portable devices which record a triangulated mesh of detail which is saved to a laptop computer file. Scans can be done in the field, saving the time and expense of dismantling ornamental detail and shipping to our shop. We have used our scanner to record sculptural detail such as finials and crockets. Now we are using it to record the complex geometry of tracery windows. The scanned files can then be used to create drawing and CNC files for shop production.

3-D Scanning by L. Schmitt of Al Slattery Masonry 3-D Scan of stone tracery window, First Presbyterian Church, Oklahoma City, OK at First Presbyterian Church, Oklahoma City, OK Page 3

Plant News - Meet “Kuka”!

Robots have been used for industrial and manufacturing applications for decades. They New Employee! have been used on automobile assembly lines Welcome Cathy Krotky and in parts manufacturing plants to perform repetitive tasks with consistent accuracy. Now we are using a 7-axis robotic milling system to carve stone. The milling head was custom designed to hold interchangeable diamond encrusted router bits. The water cooled system is programmed to follow an efficient tool path around the solid block of stone, removing ex- cess material. This is a subtractive manufacturing method. The tools are progressively changed to create refined detail. The table turns and the robotic arm articulates much like a human arm, finding the optimal angle and Cathy joins us to fill the posi- direction. Ideally this setup is suited to the tion of Bookkeeper and fabrication of multiple, identical units. Pro- Administrative Assistant. gramming and troubleshooting are time front- She brings a wealth of profes- end costs. Once the origin and correct tool sional expertise and enthusi- path are determined, the work flows 24/7. asm for getting the job done. Hand finishing by skilled cutters and carvers is required to complete undercuts, refine sculpted detail, and finish the surfaces. The heavy work is done by the robot, while the carvers are now freed to focus on the artistic Watch the video of Kuka in action. https:// portion of their work with minimal wear and www.youtube.com/watch?v=hwsagCRxDhA tear on their bodies. Far from being an archaic and static craft, decorative stone masonry is evolving rapidly, capitalizing on the best that both contemporary human skill and modern technology have to offer.

WHO’S WHO Ask a Designer— Geometric Tracery Windows President : R. John Bridges horizontal plane where the vertical jamb meets the beginning of the arch. Usually, General Manager : there is a mortar joint at this level. Off centre, Richard Bessell along the spring line we measure to find the centres for the perimeter arches. Where those V.P. Sales & Marketing : two arches meet is the apex. In the field we Laurie Wells measure the vertical height of the arch from the spring line to the apex. We also take ref- Bookkeeping & erence dimensions of typical openings or Administrative Assistant point-to-point distances to cross check with Cathy Krotky our 3-D scans. In the drafting office we lay AutoCAD over the 3-D image to generate the Equipment & Plant complex geometry. Joints are added, and cut Maintenance : Ical Lawrence Pull out your protractors and brush up on sheets for each stone are drawn. Templates your grade school geometry. Drawing geo- for stone and for stained glass are co- metric tracery windows is an exercise involv- Drafting & Design : ordinated to ensure a perfect fit. Download Tony Cirillo ing intersecting and bisecting arches, circles our Windows of Distinction poster to learn and linear elements. There is an elegant sim- more about this subject: Programming & Automation plicity to the repetitive design. We begin in http://www.oldworldstone.com/image/pdf/ the field by laser measuring the masonry Kash Jani FAQ%20Poster%20-%20Windows%20of% opening at the spring line. This is the 20Distinction.pdf

%20Windows%20of%20Distinction.pdf

http://www.oldworldstone.com/image/pdf/FAQ%20Poster%20

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OLD WORLD STONE LTD. Phone: 905- 332-5547 1151 Heritage Road The Tradition Continues... Toll Free: 1-800-281-9615 Burlington, ON L7L 4Y1 Fax: 905-319-2477 Canada Email: [email protected]

Proud members of the following The Stained Glass Association of Sealant, Waterproofing & organizations: America Restoration Institute