Spring 2010 Classes at the Arboretum

The new class schedule for the North Carolina Arboretum was recently announced. I am leading three stonework classes this spring. DIY Flagstone Paths & Patios will be offered twice, on Saturday April 10th and on Friday April 16th. In the morning session, we discuss the basics of drystone flagging: necessary site prep, the principles of good structure and varying joinery styles. In the afternoon we go outside to the stone classroom and practice the essential skills: moving stone safely, shaping individual pieces and leveling the patio.

I am offering a brand new class this spring, called Stonework Special Projects: Making a Bench on Saturday May 15th. In the morning we will discuss the design and structural issues of building a stone bench. In the afternoon we will build a freestanding bench ourselves. Topics of note including cutting stone with feathers and wedges and how to move large stones safely.

 

Radial Steps: Tread two and landing installed

Stones laid dry to test fit

It really did take two weeks to get this step installed. We had a wicked cold snap, with at least a week’s worth of days that didn’t go above freezing. But the last two days have been in the fifties and it’s felt like summer. In the image above, you are looking down onto the bottom two steps. The lowest step is eight feet across. The landing narrows down to six feet. There are small points on the outermost stones on the landing, that almost look like little horns, pointing back at the camera. Those will be cut square and columns will rise up alongside the step. Four steps will rise above the landing, with the radius reversed, curving back into the hillside.

A mason friend is restoring a chimney around the corner. I scored a whole mess of scrap bricks from him, which I have been using for fill. Because the bricks are old and some are breaking down, I am only using them inside the structure. No bricks will be used where they will be vulnerable to moisture

The image to the right is of the bluestone laid dry to test the fit of the stones. So far the templating system has worked beautifully.

Bluestone walkway

Bluestone walkway detail

I built this walkway last fall using Pennsylvania bluestone. In this image you can see both the true and full-color bluestone. The path is 42″ across and laid dry. There’s a small set of steps in the middle; the very straight line at the bottom of the image is the back edge of the top step. The steps are Tennessee sandstone, but they fit the color palette well. The path is drystone, with no mortar or concrete at all. It leads to the main entrance of a private residence.

New page and random images

Eight Stories, Nine Leaves

Eight Stories, Nine Leaves

I’ve just added a page about the Eight Leaves, Nine Stories patio pictured above.

Visitors to the Job Site

Sandstone wall detail

Working at night

This looks more like a crime scene than job site. I set up lights to work later on Monday, talking advantage of the lovely weather. Today’s nasty rain and tomorrow’s threat of wind gusts up 55 mph makes me glad I did.

Bluestone Fabrication: Making the 9-Story Patio

Bluestone Fabrication

The first designs were pencil lines on paper, as I tried to create shapes and fill the space in a balanced way. The pencil sketches were on an approximate scale. Once I had a design I liked and the clients had approved, I created the drawing above in Adobe Illustrator. I made it full scale, which means the document itself, if I could print it on a single sheet, would be exactly the size of the patio, five feet deep and almost twenty feet long. The biggest challenge was keeping the arced lines smooth. I freehanded each line, but found several shortcuts to eliminating the bumps and bounces of my hand drawn lines. I use a Wacom drawing tablet, which helps a whole lot.

You might notice that the numbering scheme is also a lettering scheme- I substantially changed the design halfway through and couldn’t start my sequencing all over again.

Since I don’t have access to a large enough printer, I had to cut the document into pieces. I outputted a couple dozen PDF files that had a shape or two on them. I twisted and turned the original document to reduce how many prints I needed. It was still a huge roll of prints. I had them done at Henco Reprographics, far and away the best printers in town. I cut each shape out, a few at a time because it proved to be so tedious. As it turned out, making the templates was just as time consuming and considerably less fun than making the stones. Though it was less dusty.

I transferred the paper shapes onto fifteen pound roofing felt. It’s considerably more durable than paper and waterproof. I fastened the paper to the felt with masking tape, to make sure my shapes didn’t morph during the cutting. Using felt for the templates was an idea I borrowed from fellow Stone Foundation member Karl Opanowicz. It worked perfectly and withstood all the abuse I could mete out.

Most of the stones had at least one straight side, which is where I started my cuts. I had to place the templates quite precisely as they barely fit on the stones. As it was, I purchased over three tons of material to find these 27 stones. There are only a couple of stones left over big enough to be cut for this design, most of which were rejected for being boring. This stone, the thickest of all of them, is sitting on the table of my Achilli bridge saw.


The Achilli bridge saw is a job site granite fabrication tool. It can support a 14 inch diamond blade and has a recirculating pump in the table reservoir that sprays water onto the blade, keeping it cool and knocking down the dust. The bluestone was so soft that I could plunge cut it, meaning I didn’t have to make multiple passes. It zipped right through.

Bluestone Fabrication
After the straight lines were cut I moved onto the arcs. I traced these lines with a piece of soapstone. It’s more durable than pencil lines, but can be washed off as desired. The wax crayons carpenters use leave permanent markings on stone. From this picture you can see how close I am to the edge of the slab.


I used a five inch Makita variable speed grinder for the curved cuts. In this image it’s outfitted with a 4 1/2 inch blade and the grip is on the wrong side; this was an early stone in my learning curve. Matt of Rockstar Marble and Granite set me on the right course by switching me to a five inch blade and swapping the grip around. I faced the blade away from me and dragged it from left to right, sending the spray of dust away from me. By holding the grinder straight up and down I was able to get very clean and deep cuts, though I had to flip several stones to finish the job. What a delightful mess.

Bluestone Fabrication

I used a cup wheel to grind off any excess along the edges of stones. While the sides aren’t visible, the tolerances between the stones are so tight, there’s no room for any extra material. During installation on site, I also used a zero tolerance wheel, another granite fabrication tool, to fix shapes and tighten the joints. These are both fairly aggressive tools and I was able to rip my way through the excess without too much trouble.

Bluestone Fabrication

Rough draft at the shop

Towards the end of the bluestone fabrication I laid it all out at my workshop. I didn’t fuss too much with the joints while I was fabricating it, figuring that there would be a lot to do on site to get it exactly right. It would have been hard to get them exactly right at the shop because the stones were varying thicknesses placed on a level surface. A slight discrepancy in level can change the way two stones interact. Most of the stones needed at least some attention to snug in the way that I wanted. The stone fabricated above- number 9- is visible at the bottom left of this image. On the patio, it partly spans the doorway, one of the reasons I chose such a thick slab.

Bluestone Fabrication

Ready to go

Details: Eight Leaves on Nine Stories

Details: Eight Leaves Nine Stories

Details: Eight Leaves on Nine Stories

The eight leaves are of blue bluestone; six are visible in the image above. The background is made up of what’s known as off-color bluestone. It runs green to brown, but I chose only the browner tones for this piece. Texture was important too. Several pieces have reeds or stalks of plants embedded in the stone’s surface.
The patio is laid dry, but the joints aren’t filled with sand or gravel, as is usually the case. This keeps the joints dark, a detail which I absolutely love.

Details: Eight Leaves Nine Stories
The nine stories is how high up this small patio is over Asheville. It’s situated on a ninth story balcony in a downtown high-rise. Thankfully there was an elevator. My big truck barely fit in the parking garage.
In these images the stone is fresh wet, having just been washed down. I’ll take further images when the stones aren’t so sopping. Stone looks best damp, not wet.

Details: Eight Leaves Nine Stories

The design was inspired by a rug fragment, seen in the top left corner of this image. I made a color study based on the sample and created a design that borrowed from the rug. The balcony railing has similar swooping lines and even some of the furniture features a subtle leaf design. The rug itself, when completed, will be placed inside the condo, opposite the balcony, designs reflecting each other through the floor-to-ceiling wall of windows.
Crafting the stones was a fascinating process which will be detailed in a forthcoming blog entry. I had full-sized templates printed from my design, shown below.

Details: Eight Leaves Nine Stories