Hmm… what have we here…?
Could it be…
Some kind of…
Hmm… what have we here…?
Could it be…
Some kind of…
Still busy with the secret second phase of the project! So here’s a nice wallpaper of the Holliday’s business end: the cab space.
I decided to show this with the natural wood color. Looks quite different from the Holliday you know, doesn’t it?
Ready to take in all the details? Can you identify all the pipes and valves? Then go grab your CK Holliday Cab Wallpaper!
Today I’m showing what certainly is my favorite result from the engine model: the partially cut through view of the engine. It shows the internal build and mechanisms inside the CK Holliday. Let’s take a look at it below, and at the end, I’ll link the pictures in large format that are suitable for wallpaper.
Because the engine is completely mechanically correct, the model can be “sliced” across to show its inside with all the components intact. It’s like having a giant saw to cut the engine in half. Here, I cut the top half of the engine through the boiler, and the bottom half through the cylinder.
Here’s the steam dome section, showing the dry pipe rising in the dome, the throttle valve link or crank, the header pipe at the rear, and even the dome covering.
One of the most intriguing part of the engine is the cylinder and piston. With the cylinder sliced open, the numerous and once hidden steam and exhaust passages can be closely examine. See also the valve slide in the steam chest, and the piston and piston rod. Note the brass valve stem packing at the rear of the steam chest. And again, the section also shows how the decorative coverings work.
At the rear, the stay bolts are visible, and show how they suspend the firebox in the boiler. The throttle rod can be seen just above the firebox’s crown sheet, along with the header pipe’s “root” in the boiler. Just below the throttle link at the back of the boiler is the brass washout plug.
I think the cut-through model really shows off what a beautifully simple, yet intrigate, machine she is. It is of course also educational, for both the steam expert and novice, because it really is the best way to see and appreciate what’s underneath all that brass and bright colors.
Ready to examine the engine yourself? Just follow this link to the picture set, and you can even select the picture closest to your desktop size and set it as your wallpaper. But be careful, you might end up looking at it all day and not get any work done.
I hope this model help you gain further insight and appreciation for the CK Holliday.
This is the last construction update. The model has now received all the parts that its 1955 counterpart had, so the model is finished.
The last piece to go on is of course the builder’s plate. The builder’s plate can be found on everything from ships, to planes, and spacecrafts. It usually contains the builder’s name or company, the place of construction, the date, and serial number. Quite accurately, it’s very much like a machinery’s “birth certificate”.
There are no rules for the builder’s plate so information varies from plate to plate. On the DRR’s twins the plates were merely part number stamping. Each plate is found on respective engine’s backhead.
Around the park’s 50th anniversary the engines finally receive proper builder’s plate. They were designed by
Michael Broggie Michael Campbell to reflect each engine’s style and period. Read more about this at MiceChat.
The markings are very simple. They read:
So there it is, the last piece of the engine. In total, there are over 3500 parts on the engine, with 676 unique parts.
But this is not the end of the blog. There will be more updates to come!
Time to dress up the cylinders and steam chests. The brownish outline below shows how the cylinder and steam chest gets “wrapped” in brass and other cover.
The decorative covering consists of a cylinder jacket, cylinder brass cap at the front, the brass cap at the rear (2 halves), the saddle side cover, the steam chest brass box, and the steam chest cover. There’s a hole at the front of the steam chest–this is for the relief valve that will be installed later.
And as promised, here’s a closeup of the pilot:
As straightforward as it can be. There’s some internal framing, as well as tension rods mounted to the top of the bumper beam. The rods keep the pilot from drooping under its own weight.
Here are some of the motion simulations that are possible in the computer.
The first one is an extension of the eccentric motion I posted a while back. This time, the main and side rods have been put in place and the crossheads (and the hidden pistons) are now in motion.
Some notes to observe:
Next simulation is the throttle valve linkage. The throttle bar (left) is linked to a valve at the top of the dry pipe (L-shaped rising pipe, right). The valve is inside this pipe and when the throttle is closed, the valve sits snug in a seat in the dry pipe. When the throttle bar is pulled, the linkage causes the valve to “pop” open and allows steam in the steam dome to enter the dry pipe, then onto each cylinder and piston.
The yellow vertical pipe immediate behind (left) of the dry pipe is the header pipe, which takes steam from the steamdome into the cab to run appliances.
And speaking of throttle, the next animation shows the throttle quadrant in action. The quadrant is notched, and a spring-loaded block with teeth “grabs” the notches to hold the throttle in place against the steam pressure acting on the throttle valve.
It all looks simple, but there are a number of subtle movements, such as the moving quadrant and the pivot of the throttle bar.
Note that to actually move the throttle, the engineer would grab the handle at the end to release the spring-loaded latching block from the quadrant. That action is not in the animation. The latching block simply slides along the edge of the quadrant instead. I used this motion to ensure that the latching block is concentric to the quadrant.
The engine’s plumbing is (almost) finished! This was, by far, the most head-scratching induced phase of the model.
Here’s a checklist of what’s done:
Just for fun, let’s look at the engine from line drawing perspective this time.
I added the pilot (cow-catcher), smokebox braces, and the deck, so that the engine now look fairly complete. Lots of other details were added since the last update, too, such as the cylinder cocks and the associated linkage, which are of course “operable”.
Here’s the right side:
Just looking at it: there’s no mistake that it’s not the Lilly Belle, or any other 4-4-0s, it’s indeed the CK Holliday. It’s the overscaled cab, the balloon stack, the long pilot, and 1000 other details that help shape the whole engine.
The smokebox braces were interesting because they actually curve inward at the front. You can see this effect in the front view:
More details on the pilot’s construction to come…