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Pinawa Heritage Sundial. A Local Government District of Pinawa Millennium Project. Grand Unveiling – July 14, 2001. Pinawa – A great place to live!. My First Sundial. The sundial was drawn in AutoCAD and a full scale plot was made. It includes a noon gap and a graph of the Equation of Time.
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Pinawa Heritage Sundial A Local Government District of Pinawa Millennium Project Grand Unveiling – July 14, 2001
My First Sundial The sundial was drawn in AutoCAD and a full scale plot was made. It includes a noon gap and a graph of the Equation of Time. The brass dial was made using a photo-etching technique. The sundial was raffled to raise funds for the project.
Design – Dial Plate • OUTER DIAL • Local Apparent Time: solar time as derived by the real sun at any particular location. • Symmetrical layout suited for the granite tiles. Latitude:50°08'48" NorthLongitude:95°52'31" West
Design – Dial Plate • INNER DIAL • Zonal Solar Time: local apparent time with a longitude correction but without correction for the Equation of Time. • Results in an hour line shift of ~23.5 minutes earlier. Latitude:50°08'48" NorthLongitude:95°52'31" West • Indicates Daylight Saving Time.
Design – Getting Started • Determine latitude and longitude of the dial centre. • Determine hour line angles relative to noon. • Establish the true north line. Points to the North Celestial Pole. • Establish position of the 2 dial centres as a result of the wide gnomon – 6 inches. Latitude:50°08'48" NorthLongitude:95°52'31" West
Design – Getting Started • Initial hour line angles calculated manually. • Graduated to spreadsheets for greater accuracy. • Discovered free sundial design software-ZONWVLAK. • Software produces a set of hour lines exportable in dxf (drawing exchange format). Latitude:50°08'48" NorthLongitude:95°52'31" West
Design – Getting Started • dxf file used in AutoCAD to create all the detailed drawings. • Hour line angles measured in AutoCAD and checked against spreadsheets. • Layout tables and checks developed. Latitude:50°08'48" NorthLongitude:95°52'31" West
Construction – Getting Started • Barrie Burnett-Pinawa’s resident hobby surveyor. • He established the latitude and longitude. • He established true north. • He surveyed in all the hour line angles. • He laid out the dial base and positioned the gnomon.
Construction – Getting Started This device was used to confirm the position of the true north line. • The line was first transposed to the parking lot and markers established. • At precisely local noon the two edges of the light band were marked. True north line found. • Compare to established line. It was right on!
Design – Dial Plate • 38.5’ wide (east-west),40.5’ long (north-south), ~1560 ft2. • Elevated 18” using ~65 yd3. of crushed limestone. • Consists of a central medallion, inner dial and outer dial. • The central medallion and outer dial are made from polished granite with sandblasted images.
Design – Dial Plate • ~315 sq. ft. of granite 1.875” thick, 8860 lb. • The inner dial and borders are ~ 580 ft2. of red/black and grey tumbled pavers. • The hour lines are made from used railroad track. • The 92-15 minute markers are machined from 1/2” diameter brass rod.
Design – Dial Plate • 150 ft. of granite block retaining wall surrounds the dial base. • Each block is 15 inches square and 48 inches long. • Each block weighs ~1125 lb., ~40,000 lb. • A 6” noon gap corrects for the gnomon width.
Construction – Dial Plate • Our sign! • 1999 - Just a flat vacant piece of land.
Construction – Dial Plate After clearing the organic material 4-16” diameter by 16 ft. holes were drilled for the concrete piles. 4 cages- 1”x10’ threaded rod welded to 20M rebar for 36’ with 10-10” diameter 10M rebar rings
Construction – Dial Plate 2 piles on the north-south line and 2 on the east-west line. The 18” high base was built using limestone and the help of the residents of the Milner Ridge Correctional Centre.
Construction – Dial Plate The piles with threaded rods for securing the gnomon base. The gnomon drainage pipes are visible. The 8”x12” hollow steel section is bolted to the east-west piles. Plywood templates were used for positioning the holes for the threaded rods.
Design - Gnomon • All images were created by the artists using Adobe Illustrator. • The manufacturer required an AutoCAD file for their plasma cutting machine. • The Adobe dxf (drawing exchange format) file was not adequate as it used splines for the curves.
Design - Gnomon • The entire drawing was traced using AutoCAD with the appropriate drawing tools. • A full scale paper mock-up of the gnomon was constructed to check the design. • The AutoCAD file was emailed to the supplier and the gnomon was cut out using 1/2” steel plate.
Design - Gnomon • The style height is equal to latitude at the dial’s centre: 50°08'48" • The gnomon is about 16 ft. long and 17.5 ft. high. • The images cut into the plate steel reflect those illustrated on the granite icon tiles.
Construction - Gnomon 12”x 12”, 4”x 8”, 6”x 6”, 3/8” thick hollow steel sections form the base of the structure. Computer controlled plasma cut 1/2” (1/4”) mild steel plate. 10 pieces in total.
Construction - Gnomon The gnomon is welded and ready for sandblasting. (plug welded images, hand forged 1”x3” trim) Gnomon construction in the machine shop.
Construction - Gnomon The gnomon is being removed from the shop for sandblasting. • The sandblasting process. • Medium grade silica sand. • Portable sandblaster/diesel compressor.
Construction - Gnomon Matt grey colour after the mill coating removed. Surface oxidizes rapidly and uniformly. • The hollow steel section gnomon base: • 8”x 12” positioned on east – west piles. • 12” x 12” positioned on north – south piles.
Construction - Gnomon The Galion was used to position the gnomon on the 12’ x 12’ hollow steel section. The gnomon was not released until it was secured in position. It was able to balance on its own even before welding.
Construction - Gnomon A portable welder was used to attach the gnomon to it’s support structure. Barrie Burnett was set up over one of the reference markers to ensure the correct orientation of the gnomon.
Construction - Gnomon “The Gnomoneers” Steve Berry, Bill Macdonald, Ervin Hemminger, Glenn Graham, Carl Sabanski, Clive Schultz “The Gnomon Erectors”Barrie Burnett, Fred Betker, Al Abraham, Brian Dyck, Leonard Scholz, Clive Schultz, Carl Sabanski
Construction - Gnomon • Erected November 1, 2000 • Time capsule placed in the base. • The oxidization began as soon as the gnomon was sandblasted and is a unique characteristic of the structure. It is always changing as the rain paints new patterns on the steel.
Design – Hour Lines • Donated recycled railroad track was used. Made in 1934 and weighs 85 lb./yd. • 225 ft. of rail was used weighing 6375 lb. • The track was sandblasted and coated with a clear finish. This finish was not permanent and wore away allowing the rail to oxidize.
Design – Hour Lines • Inner dial - 169 ft. of rail from 7.2 ft. (204 lb.) to 14.3 ft. (405 lb.) • Outer dial – 56 ft. of rail from 25 in. (59 lb.) to 7 ft. (198 lb.) • 92 15-minute markers machined from 1/2” solid brass stock were set into holes drilled in the grey pavers.
Design – Hour Lines • 16- inner dial hour lines are marked in Arabic numbers sandblasted & painted into the grey pavers & indicate Daylight Saving Time. • 15- outer dial hour lines are marked in Roman numerals sandblasted and painted into large granite stones collected along the river shore line.
Construction – Hour Lines 7- 36 ft. long railroad tracks were donated. To fit the trailer they had to be cut into 28 and 8 ft. pieces. The rails were cut using a band saw. A drawing indicated the cut angles and length of both sides of the rail. The finished rails were within a couple mm of the specifications.
Construction – Hour Lines The rails were sandblasted and a clear seal coat was applied. The longer rails ready to be installed. As the rails age and the seal coat wears off the rails are slowly oxidizing.
Design – Granite Icon Tiles • 12 icons illustrate the history of the Eastern Manitoba region as well as well as important factors that played a role in the development of the region. • Three additional icons complete the dial plate.
Design – Granite Icon Tiles • Glaciation • Glacial Lake Agassiz • First Peoples: Introduction of Stone Tools • First Peoples: Introduction of New Technologies • The Coming of the Europeans: Voyageur Fur Traders
Design – Granite Icon Tiles • Industry-Agriculture, Forestry and Mining • Modern Transportation-Rail, Air and Road • Development of the Winnipeg River-”Old Pinawa” • Further Development of the Winnipeg River
Design – Granite Icon Tiles • Whiteshell Provincial Park • Wildlife • Research & Development -Atomic Energy of Canada Limited • The Day Sky • The Night Sky • The Earth and Sun
Construction – Granite Icon Tiles Sheldon secures a rubber material that was applied to all the areas not to be sandblasted. Each tile was then sandblasted until the artists were satisfied that it met their requirements.
Construction – Granite Icon Tiles Tiles in the process of being sandblasted. The last part of the job was to paint the sandblasted areas of all the tiles and move them to the site.
Construction – Dial Plate The central medallion consisting of 4 granite tiles was positioned first on a bed of sand. The pavers for the inner dial were laid on sand to create one continuous field. The sections between the hour lines do not look like they have been filled in.
Construction – Dial Plate The centre line for each hour line was surveyed. An offset found each edge of the rail. A chalk line was snapped and the pavers were cut using a cut-off saw. The pavers are removed for the rail installation. After the rails are leveled and surveyed into position the pavers are put back into position.
Construction – Dial Plate The inner dial is complete: central medallion, hour lines, red/black pavers and grey border pavers. The outer dial rails are placed into position and the granite tiles placed between them.
Construction – Dial Plate The last piece of granite! The rails have been positioned and the sand bed is ready for the remaining tiles.
Construction – Dial Plate The dial plate is there but you still can’t tell what time it is unless you are familiar with its layout. The hour markers still need to be done. A view of the dial from the northwest. The sun is shining and there is a great shadow.
Construction – Dial Plate The granite blocks for the outer wall are installed. Each weighs ~1125 lb. and there are 36 of them – 150 ft. How do you place and position a heavy granite block? Ice! You need a lot of freezer space for 120+ blocks of ice. It really works!
Construction – Dial Plate The completed retaining wall. Granite stones are used for the outer dial hour markers. The inner dial markers are set into the pavers. The noon gap is seen in this photo.
Construction – Dial Plate Each hour marker is unique. Each 15 minute interval is marked with a brass button set into the grey pavers.
The Sundial “TIME TO CELEBRATE”
The Sundial A view illustrating many of the components of the sundial. An excellent shadow. Once the time is determined on the inner dial all that needs to done is to correct for the Equation of Time. Within 5 minutes of clock time.
The Grand Unveiling Lillian Tankard (Culture and Tourism), Culture, Heritage & Tourism Minister Ron Lemieux, MLA Darren Praznik, Liberal Leader Jon Gerrard, Mayor Len Simpson, Resident Administrator Gary Hanna and Cst. Brunet Mr. Gnomon July 14, 2001