Highball Sim

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.

The CK Holliday Cut-Through Engine Model.

It’s sure been slow around here, hasn’t it? That’s because I’ve been working on another phase of this project.

Here’s something to look at, meanwhile: the completed engine.

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:

• National Boiler registration number (for the CK Holliday, it’s NB 642, [year] 1954).
• Working Pressure: 200[psi]
• ???: 213[psi]
• Disney’s serial number: 12554-55

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!

Some new shots of the 3d model (without materials). Nearly completed now.

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:

• The motion simulates the engine running at about 2.5mph
• The offset of the two pistons is more obvious when watching the two crossheads move relative to each other
• The tendency for the lifting shaft, link, and the reverser bar (out of view) to nudge or swing “forward” as the wheels spin. This is why the reverser bar arc is notched. In the animation watch the lifting shaft carefully for this effect
• The mechanical lubricator link can be seen in the upper half of the animation. It’s driven off the left valve stem
• The empty slots at the crosshead/piston rod junction will receive the piston/crosshead key

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:

• Dry pipe
• Header
• Steam gauge supply
• Blower
• Air compressor steam supply
• Atomizer (steam)
• Hydrostatic lubricator, steam in
• Hydrostatic lubricator, oil out
• Boiler water sight glass, supply and return
• Boiler water sight glass, drain
• Left injector: water feed from tender, steam supply, and overflow
• Right injector: water feed from tender, steam supply, and overflow
• Left and right injecting water feed to boiler
• Dual try-cocks
• Air compressor exhaust
• Air compressor compressed air line to air tank
• Air compressor governor line
• Air line from tank to brake stand
• Air line from equalizing tank to brake stand
• Air line from brake stand to left and right brake cylinders
• Air line from brake stand to duplex gauge, black pointer
• Air line from brake stand to duplex gauge, red pointer
• Air tank condensate drain
• Atomizer (oil)
• Air line from brake stand to tender
• Blowdown (water)
• Blowdown (air line)
• Mechanical lubricator feed line left and right

Not completed:

• Compressed air umbilical hookup
• Try-cock funnel
• Equalizing tank condensate drain

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…

I couldn’t find the manufacturer’s name of the mechanical lubricator used on the DRR, so I made a “typical” version of the device.

The mechanical lubricator is so called because it uses mechanical crank and cam to force the oil into the system needing lubrication, in this case, the two cylinders, containing the valves and pistons. The other type of lubricator is the hydrostatic, which uses the steam to carry the oil.

The twins on the Disneyland Railroad aren’t “supposed” to have mechanical lubricator. On the Holliday, one can see false oil cups mounted on top each cylinder. On both engines, the mechanical lubricator is mounted on the left (non-park) side of the engine. To even further hide this device, the lubrication tubes are hidden under the boiler jacket when possible, or otherwise tucked away into the shadow of the running board. In fact, they’re so well hidden that these tubes are quite difficult to trace from photographs–I had to use some imagination to route these tubes realistically.

Below are some of the parts of the lubricator, and how they fit on the engine:

The terminal end of the tubes at the steam chests will be hidden under the steam chest covers.

Each time the valve rod moves back or forth, that is, when the engine is in motion, the “Motion Link”, annotated above, moves a small crank on the interior side of the engine. Each time it cranks, a small amount of oil is ejected into the cylinders.

Here’s a video from YouTube demonstrating the action. The cover is open so you can see the cam working inside. Note also that the crank arm is driven by an eccentric instead of the valve stem.

[youtube http://www.youtube.com/watch?v=KQlsFHBYaI4&w=480&h=360]