Sunday, October 26, 2014

Crafting the Roundhouse Roof

When my roundhouse walls arrived from Michael Rebeiro, they came with two sets of roof templates.  Since the roof is peaked, there were separate templates for the front facing section and for the rear section of roof.  From this side view you can see how the roof is constructed.


The roof is designed to be supported by the walls and seven wood trusses.  My options were to make the roof out of the 16 roof templates (or from some material cut to the dimensions of the templates) or to use the templates to make two roofs -- one that would go from side to side and cover the front half of the roundhouse, and the other to cover the rear.  I wanted to be able to remove the roof for viewing and servicing if necessary, and the idea of removing 16 separate pieces of roof seem impractical.  So I tried cutting a piece of .030 (1/32) inch styrene sheet using the front roof templates laid side by side and taped to the styrene as a pattern.  Here you can see the templates.  You can also see that something was very wrong with the roof!


If you look at the right side of the roof, you will see a gap between the end of the roof and the side wall.  (Ignore the styrene extending over the tracks.  I hadn't yet cut the front of the roof to the templates.)  It appeared that the roof was too short!  Here is a closer look at the right side.


There was a gap of more than an inch.  At first I was nonplussed by the shortfall.  How could the templates be undersized?   Then I remembered that when Mike Rebeiro sent me the first castings for the roundhouse -- which we discovered was too small -- he had sent me the roof templates for that model.  I quickly checked the templates for the second version with the templates from the first.  Sure enough, it appeared that Mike had accidently shipped the smaller templates with the new roundhouse.  Just to be sure, I placed the old front wall on the roof for the larger roundhouse.  It was a perfect fit!


That solved the mystery, but when I contacted Mike to request a second set of roof templates, I learned that he was out of the laser board that he used to make the templates, and a new shipment was not expected for several weeks.  Not wanting to wait, I decided to forge ahead and make the roof without the roof templates.  My solution?  Use the floor templates, which were the correct size for the new roundhouse walls.  The floor templates abutted each other along the same lines where the roof templates ought to meet.  It was necessary to do some fudging with the templates, as the roof extends beyond the front wall of the building and the floor templates do not.  With a little adjustment, I was able to cut out new front and rear roof sections.


The front and rear roof sections are taped together here, so that I could get a sense of how the roof would set on the roundhouse walls.  My thinking is that the rear section will be cemented to the walls and trusses and fixed in place once the building is finished.  The front part will have small pieces of 1/8 inch styrene stock glued underneath, so that the roof will rest on the front and side walls without slipping.

The next step in constructing the roof was to cut the holes in the rear section for the roof vents (which sit just behind the peak of the roof on the prototype) and for the smoke stacks.  Mike had cast the vents and caps when he made the walls, but he was unsure how to model the stacks that vent smoke from the locomotives.  I decided to use 5/16 square styrene tubing and cut holes in the roof accordingly.


Here you can see seven of the roof vents ready for mounting on the roof, but not yet painted or glued together.   Below is a  photo of the roof vents after painting.  The wooden vents were painted roof brown while the metal caps are grimy black.



 The kit included eight vents, but in reviewing the HABS/HAER drawings from the Library of Congress, I learned that there were never any vents or stacks on the eighth stall at the far left.  When the original six stall roundhouse was rebuilt after a fire in the early 20th century, the left-most stall was used as a paint shop, not for parking steam engines.  Today there is a fine brick paint shop adjacent to the roundhouse and the eighth stall currently holds the largest of the 2-8-2 mikados.  I opted to go with the historical record and leave off the eighth vent and stack.


From the rear you can see the roof vents and the square holes for the locomotive smoke stacks.  I am currently working on developing CAD drawings  for the stacks for 3-D printing.  We shall see how that works out.  An alternate plan would be a length of 5/16 inch square styrene with a flat cap.


From the side you can see how the roof will look when finished.  The rear overhang appears to extend out too far -- some four feet!  I will trim the edges when making the final adjustments.  I can't install the roof yet, since it has to rest on the seven interior roof trusses, which I am not ready to put in place.  I am working on a plan to light the interior using surface mounted LEDs suspended from the trusses, and that needs to be in place before I secure the roof.

The roundhouse is temporarily on hold while I construct the turntable.  The two projects have to be completed together in order for everything to fit correctly.  My next post will outline construction of the 65 foot steel girder turntable from Kitwood Models in the U.K., which replicates exactly the turntable and pit that currently occupy the space in front of the EBT roundhouse.

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