The Pinawa Heritage Sundial

The question of how to finish the sides of the dial was a detail that needed to be resolved. A number of methods were evaluated to construct a retaining wall. It was finally decided to use granite blocks 15 inches square and 48 inches long. Each block had two cut sides and 4 split sides. The 15 inch limit is due to the fact that this was the maximum thickness that the splitter at the quarry could handle. There were 36 blocks required, each weighing approximately 1125 pounds. Two blocks are left out on the south side to accommodate the ramp. The retaining wall is 150 ft. in length and weighs about 40,000 pounds. The landscape contractor was hired again to help place the granite blocks. There was still one situation to be handled. How do you position blocks that weigh 1125 pounds each? A shelf was created around the perimeter of the dial plate to within an inch of the elevation required for the blocks. This required cutting back on the north, south and west sides and building up on the east side. The shelf was compacted to make it as stable as possible. For over two weeks I was making ice cubes. These were made in 4 litre ice cream pails and were each 2.5 inches thick. A total of 108 were needed with a number of spares. Needless to say, three additional freezers were enlisted at the homes of volunteers to store the ice while I used ours to manufacture them. Once completed they were all moved to one freezer. You may be wondering what this has to do with the granite blocks. Check out the photos.

	Lance is screeding the sand to the correct elevation for the granite blocks.

To position the granite blocks ice was used. Three cubes were used for each block. The ice was not completely flat when the water froze so a hair drier was used to try to level them. This worked okay but concentrated the heat in too small an area. Any ideas?

	The first block is placed. The ice allowed the straps or forks to be easily removed once the block was set down. The 1125 lb. block of granite could easily be shifted on the ice to any position. Even by hand!

It was easy to level the cubes of ice by just rubbing them on the surface of the granite until they melted. As the ice under the blocks melted the blocks were kept roughly in position. Just before a block would touch down on the shelf it was moved into its final position. It worked great!

	The 36 granite blocks were set into place and the retaining wall was complete. Two blocks were left out on the south side for the ramp. The ramp allows for wheelchair access to the dial plate.




Local Government District of Pinawa