Un-machined Kit.NOTE: Machining & Assembly required.3⅛" diameter x 12⅝" overall height including the 4" high smokestackThis boiler will easily run the PM Research No 2, No 3 and No 5 steam engines for light-duty use and demonstration purposes.Popular around the turn of the century because of their simplicity and small floor space requirement, the vertical multi-flue boiler is still popular today for the same reasons. Today, however it also makes a handsome showpiece.The boiler is constructed of copper with four aluminium castings comprising of the base, door, door frame and smoke box cover. The tube sheets are flanged and punched. All hardware, bar stock, silver solder, working drawings, etc are included, along with a finished safety valve and water gauge.The firebox is 3" diameter x 2½" high. The door opening is 1½" high x 2" wide. The water space is 3½" high. There are thirteen ⅜" diameter flues, 61 square inches of heating surface, 20 cubic inches volume.We recommend the use of distilled water when using this boiler.The BLR-1 kit includes four easy machining aluminium castings, all copper tubing and tube sheets, all hardware and bar stock required and a complete set of working drawings.Also includes:One each SOLDERFLUX Silver Solder and Flux kit.One each WG-1 Water Gauge.One each SV-1 Safety Valve