Kozo K-27 Boiler

Part A

The steam dome base is approximately 2.3" diameter by 0.75" thick. The throttle tube will attach to the hole on the side. May 15, 2023.

These are the phosphor bronze smokebox studs that will be soldered to the front sheet of the boiler to attach the smokebox. May 20, 2023.

The larger bushing is for the steam manifold and the smaller is one of the blow-off valve bushings. These are made from phosphor bronze and will be soldered to the firebox. May 21, 2023.

The second blow-off valve bushing and the water gauge bushing. May 27, 2023.

These are the two water inlet fittings that will be at the front of the boiler to feed water into the boiler. May 28, 2023.

An alignment stud on the left to align the water fill bushing and one of the blower pipe bushings. The blower pipe will be 1/4" copper tubing. May 29, 2023.

Today I picked up an expensive 1/8" x 12" x 36" sheet of copper for the various firebox parts. This image shows how they might be cut out from the sheet. July 01, 2023.

The copper disk for the tube sheet has been cut from the 0.125 thick sheet and is about 6.5" in diameter. The wooden disks will be used to form the rim on the tube sheet. The right slightly smaller disk has a radius over which the copper will be formed. The larger disk will be a backing plate during the forming process and will also be used later to true up the boiler shell. July 04, 2023.

This is the front tube sheet with the initial forming completed. The copper had to be annealed (heated to 750 F) about ten times during the forming of the outer rim to soften the copper after it had been work hardened. Holes for the tubes and the cleanup of the outer circumference will be completed in a future step. July 8, 2023.

A look at the backhead sheet and formers before any of the forming work has started. July 15, 2023.

The backhead after forming the rim around the sides and top. July 16, 2023.

These are the blanks for the firebox end sheets and the formers that will be used to put the rim around three of the edges. July 22, 2023.

The firebox end sheets after forming the lip on three sides. July 23, 2023.

This is the copper blank for the throat sheet and the formers that will be used to form the sides of the throat sheet. July 29, 2023,

The throat sheet after heating a few times and forming the side radius. July 29, 2023.

A semi-circle has been cut in the throat sheet and the formers created which will be used to form the lip that will cradle the boiler tube. July 30, 2023.

The throat sheet after forming the boiler tube lip. It will need to be cleaned up a bit and some straightening of the upper ends. July 30, 2023.

This weekend I spent time making some more of the boiler fittings. Handrail studs, throttle base, jacket rib studs, steam outlet and blower outlet. August 6, 2023.

The mounting base for the generator and the clamps for the steam dome base. August 12, 2023.

The curved mount for the bell stand and the four mounting points for the running boards. All of these will be soldered to the boiler tube. August 13, 2023.

Today was a lot of repetitive machining trying to crank out all of the staybolts for the firebox. These are 1/4" phosphor bronze and about 3/4" long. August 20, 20223.

A total of 84 parts for this construction segment with the air compressor base (long brass part at lower left) and the tubing worked on today. August 26, 2023.