Workday Wednesday's Accomplishments - Nov.29
Prior to the usual Workday Wednesday this week, I spent some time thinking about and experimenting with the tower roof for the Craig Leigh station.
The tower on the Craig Leigh station was originally constructed with a light plywood form sheathed in styrene. The styrene was painted to represent a copper roof. The original construction was done in the IPP&W shop including the styrene sheathing but was painted expertly by John Obonsiwin's wife. She also painted the main station roof to match.
The tower was built of Jigstones with a nominal outside measurement of 10 inches square. A base was made with strips of wood glued along its outer edges so that the base sat overtop the tower and held by the glued strips, essentially forming a cover and platform. The tower roof was mounted on top of this platform.
The tower roof mounted almost flush with the platform edges. In the rain, water would wash down the sloping roof and by capillary action would be sucked under the roof and against the plywood platform. Eventually the plywood platform rotted and totally disintegrated with the rot extending about an inch and a half up the sloping inner plywood walls of the roof. The balance of the roof form was sound. This picture shows the serious damage to the roof form.
I can still remember 15 years later what a bear of a job it was in the beginning to build that plywood form to carry the sheathing. Working out the angles on the sides and cutting them precisely was a frustrating experience. After some serious thinking I arrived at a scheme for rebuilding that would use the existing materials as a starting point.
First I cleaned away all the rotted wood along the bottom edge...one side was almost intact while the other three had a significant amount of deteriorated wood removed. Then I added a piece of light plywood screwed to the inside of the roof and extending down to just short of the edge of the original styrene roofing.
Against this plywood piece I screwed on a strip of material the same thickness as the original roof walls giving the following end result.
Now the original styrene roofing could be glued in place assured of a perfect fit.
Lastly was the issue of the platform for mounting the roof on the Jigstone tower. The old platform came out to the edges of the sloping roof sides. It was constructed that way to allow for a fit over the tower with the strips glued on the outer edge preventing it from being knocked out of position. Since experience has shown that approach leads to water entering causing rot, I decided to make a new platform much smaller and with a "plug" that fits inside the tower walls to hold it in place. The end result is shown above.
At this point Bill Scobie and I talked through the alternatives. The proposed approach using the existing materials vs scratchbuiding a completely new roof. We decided to give the proposed approach a try.
Wednesday morning, Bernie Goodman, Bill Scobie, :Lawrence Watkins and myself met Fred at the shop with the old wood stove nicely heating the area. Bernie took some pictures to supplement the ones that I took - thank you Bernie for acting as resident photographer recording our joint efforts.
We went straight to work. The main roof of the station was removed and the inside was surprisingly sound, undamaged by water. We vacuumed out the dirt and cobwebs before resetting the roof in place.
Bernie undertook applying grey silicone sealant along the front wall of the station and then the exacting task of black silicone around the roof. edges where the black roll roofing meets the styrene sheathing.
Since we did not have sanded grout on hand we deferred grouting the mortar lines on the new stone pieces installed last week as well as painting them.
Next was to tackle the tower roof using the newly hatched plan. The screws temporarily holding the added wooden supports to the form were released and the pieces were glued with Titebond 3 and clamped. Here I am getting the Titebond 3 glue container open.
The screws were backed out and glue was applied. The screws were then reset to hold everything in place.
Lastly clamps were applied and the screws were removed. The assembly was then put aside for the glue to set.
Next step was to paint the sides of the form and the separate roof sheathing with contact cement.
Once the contact cement had dried sufficiently, the styrene sheathing was glued down. The fit was almost perfect with a slight imperfection in one corner. That corner will be turned toward the back to put it out of sight.
Here is the final product.
Lawrence and Fred kept a close watch on the progress.
While the contact cement was drying, there was a general discussion on the design of the new Glen Hammond station.
The shade tree architects determined the sizing of doors and windows.
The window placement was roughly delineated so the number of windows needed could be determined.
Then came the tricky issue of roof overhang and the sizing of the station operator agent's bay. The initial thought was to have the roof overhang sufficient to cover the bay but closer examination showed that to be impractical. Eventually the roof overhang was set at 4 scale feet and the operator's bay would have its own gabled roof with short valleys where it joins the main roof.. These decisions will allow the cutting of plywood roof "rafters" and light plywood subroofing before construction actually begins sometime in January.
During the past week, Doug Culham cut a few "miles" of scale 1x4's to use as battens for the board and batten construction planned for the new GH station. Many thanks to Doug for his efforts!
Toward the end of the session, Pat Brennan dropped by and warmed himself in front of the wood stove.
Lawrence also gave an update on his efforts to restore the Rat Portage station. He reported that in examining the station at his home, the base was rotted in some areas. He has a plan for making repairs.
Next week, the plan is to mount the tower roof back on the tower and finish the stonework so we can declare the restoration of the Craig Leigh main station finished. A break in building maintenance is proposed at that point until after New Years.
Thanks to Doug for sending along this synopsis of the recent WDWD session.
Thanks to Bernie for snapping the pics and to Bill & Lawrence for their continued efforts with the crew!
Pat, great seeing that smile of yours as well!
All the best, the WDWD "off season" crew
Ottawa, Ontario, Canada
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