This is the third water tower I have built. The customer specified an extra tall tower (19 inches to the platform base) and an extra wide tank (4 inch dia). This tower is the first pure scratch build. The other two were customized Plastruct kits which incidentally Alan Graziano designed for Plastruct.
The tank on the left is the kit standard 3.75 inch dia and about 4 in tall. The custom tank is 4 inch dia by about 5 in tall. The platform has been modified to include two 80 mil thick styrene discs. The set that comes with the kit I found to be too thin. The purpose of the second disc is to act as glue surface for the railing. It is important to use a compass to scribe pencil lines on the top and bottom of the platform at the diameter of the tank for accurate placement of the tank and hemispherical bottom. It is also recommended to place pencil marks n the bottom to mark the four locations (0, 90, 180, 270 degrees) for the vertical struts.
The cone is Plastruct VC-96. It is a little expensive but is thick and very sturdy. Plus I want the lid to be removable so a customer can add or replace a light if desired. The cone could be made much more inexpensively with 10 mil thick styrene. The VC-96 is starts out at 6 inches at the base and can be easily cut down to various diameters. The inside is stepped making cutting very easy. I used an Exacto blade to scribe and break the plastic.
Once the tank and railing are glued to the platform. I turned it upside down and glued the bottom of the tank (VHH-400VG). Next glue the legs and let the assembly sit overnight. Note before I glued the bottom to the platform I drilled holes in it plus the platform to accept a TB-16 down tube. The holes are necessary if one wants to add a light to the roof. The TB-16 runs all the way up to the top of the tank so it can act as a conduit for wires. Note - make sure the opening in the railing lines up one of the leg supports since the ladder will go here.
Once the glue for the legs dried it was time for the horizontal bracing (C-6). I cut spacers from hardboard to make sure all the braces lined up.
Next glue in the diagonal bracing. The kit supplies MR-40 round but I find these kind of flimsy. I used black TB-2 tubing instead since these are plastic coated brass. They help stiffen up the structure considerably especially since I need worry about shipping.
Next up will be finishing the diagonal bracing plus the ladder, drain pipe and base assembly. Hopefully I will these done in the next few days. Below is a picture of this tank along side a 'standard' one I have on my layout. The normal design calls for a 3.25 in diam tank 6 inches high on a platform that is 15 inches high. The small tube on top will house a red flashing LED unit.