Large Scale Central

Submarine Transport for the Triple O


All the glue was dry on the future carrier and the paint was dry on the sub, so it was time to take the components out to the railroad and start figuring out how to make this plan work. This began with a reminder of how big this will ultimately be.

I moved the whole assembly to a curve to see if I could actually make this thing do a circuit.

Oof-dah, but that’s going to be a challenge! I am sure that there is math that would have allowed me to quickly figure out the length of the connection between the trucks and the cradle, but that would be entirely lacking in fun and out of character for Triple O engineering. That’s why I got out tongue depressors and thumb tacks to enable temporary lash-ups to test lengths and pivot points.

Now that I was moving stuff about, Kid-zilla joined me for this rigorous testing and design phase. That, though, will have to wait until tomorrow!



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That overhang on the curve doesn’t look as bad as I was expecting it to be, so after some engineering and building fun that will look good rolling around the layout! I may have to order one built for the Arizona connection to the Triple O (please do not ask me to spell it out) Olakai shoes are a hard enough one for me!

We have the sailing locomotive to head that train! :palm_tree::nerd_face: :palm_tree:

Yesterday, Kid-zilla and I performed the complete 0-5-0 powered test of the contraption. It navigated turns…

…entered the tunnel complex…

…and successfully exited the other side!

Note that for this test, the cradle pivoted beneath the tongue depressor. My original idea was to have the carrier fixed to its hangers and then let the trucks pivot beneath those. I think it will look better and be a bit stronger. We’ll get out our thumb tacks, rubber bands, and tongue depressors to try that arrangement today. Looking ahead, I am guessing the weight of the submarine may require ballast fore and aft to keep this tracking correctly. If that is the case, I think we may have some fun, build some “hoppers” on each end of the trucks’ platforms, and fill those with gravel to balance out the weight.

This project has utterly derailed my declared Triple O - 2023 Plans & Objectives, in the end, a plan is just a starting point from which to deviate!

More to follow…


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Excellent WORK so far gentlemen !!!

Progress is challenging yet rewarding!!!

Thanks, @Rooster ! We are going slowly to let it stay fun!

Today’s efforts included an effort to fix one of the pivot points, this time on the trucks, to see how it would track. We were able to rig small clamps to at least minimize the amount of pivot on the cradle itself. Kid-zilla demostrates in the 0-5-0 trials below:

This led to the all important Diesel Dan trials:

Video: Diesel Dan Pulls the Submarine Carrier

This more or less validated the design. The tongue depressors still pivoted a bit, and that did show this beast would track better if they could play. I suspected, however, that allowing both trucks and cradle to pivot under the connecting arms would mean that we could not push this car. We rearranged some thumbtacks, put Diesel Dan in reverse, and got the anticipated pile-up.

The rock, by the way, was a convenient counterweight!

Today’s trials have convinced me that:

  1. This thing needs to be as articulated as possible to allow successful pulling. This means a pivot point at the trucks and on both ends of the cradle.
  2. I will have to beef up both ends of the cradle to mount a pivot area.
  3. I will also have to design a mechanism to lock the connecting arms to allow for successful pushing. I am thinking of either a post on either side that Kid-zilla could raise or lower or something that would swing up and hold it in place, like you see on the guns of some World War II ear tanks and self-propelled guns.

Questions answered, new questions posed…the quest continues!


Would some kind of spring mounted on the end of the tongue depressor under the rock and connected to the middle of the right end of the truck mount prevent this? Even a rubber band or similar might help.

Bob (@wengnut ),

I think it might. I am still leaning towards some sort of static locking device. I anticipate that this rig will usually end up pulled under traction. A spring or rubber band, while viable, are also points of failure. In the end, this has to be a.) functional, b.) available, and c.) durable, as, in the 1:24-ish scale PLAYMOBIL world, these trump all other considerations. Beyond the goal of an item that straddles the line between toy and model, the reality of tropical conditions near the coast are real engineering considerations. Springs and rubber bands are short-lived in these conditions!

As I ponder the solution, Kid-zilla and I proceeded where we could. I helped him to mask…

…and paint the lower pressure hull a color he deemed a good “oxide red.”

We’ve done this for rockets, so the results were pretty good…

…even if I had to help him a bit with the rattle can! He selected a deep blue for the upper portion, a color he felt would help camouflage the vessel while transiting on the surface. We’ll apply that tomorrow, then apply the prop. After that, I will hand the submarine over to him for final fitting out.

I will still have to maintain oversight of the transport car. Today, we bought the hardware to connect the trucks to the carrier. We also bought some small 1" nails to reinforce the joints. As the complexity of the project has risen, so has my concern about its durability! I tapped some holes with the Dremel, and he helped me drive in the nails.

My first tap holes were too large, and he ended up coating the nails in TiteBond III and sliding in the nails. To be frank, I wish I had made the same “mistake” with all the holes. Hammering in those nails did burst a few glue bonds!

This week, we’ll build up the forward and after platforms of the cradle. Hopefully, we’ll also cut, drill, and mount the arms to connect the cradle to the trucks. That will enable a test assembly and a second Diesel Dan test. This will determine what tweaks, to include any locks on the cradle’s swing, we will need to devise. That being determined, we can proceed to sanding and sealing then detailing and painting. I’ve got some stirrup-type steps and brake wheels on hand. We can get hold down chains from the craft store.

Updates as the situation merits!

Have a Glorious Fourth!



Kid-zilla, has become a repurposer after my own heart, why not call the ship USS Nemo

Thanks! He has a good eye for this sort of thing!

Today, however, he learned that you should probably mask before painting…

Ooops…So I had him re-mask and repaint the lower hull.

No harm done, and learning happened. All is well.

We next attacked the cradle, beefing up the area where the attachment arms will pivot.

I am still working on a lock to allow him to push this around. I wanted a thick deck to enable whatever drills, screws, or bolts are in the future!

Finally, we began to prep the platforms that fit over the trucks for painting, sanding and sealing both in preparation for a coat of Navy Grey!

We are both beginning to see an end to this project, and I sense he is growing a bit impatient with it. Nonetheless, tomorrow is the Fourth of July, so we have a parade to attend, burgers to grill (and trains to run while doing so!), and fireworks to watch. I suspect beyond painting the upper hull of the submarine, this project will see little progress as we celebrate the “Glorious Fourth.”

Happy Fourth of July to All!



Slow progress. The submarine got its final coat of paint…

…and later its propellor. I also drove some 1" brads into all the connection points. Naturally, I forgot to drill tap holes, so there was some minor splitting. Good thing all the TiteBond III had dried!

The whole was a bit too tight to fit in the cradle…

…so today I did some Dremel-work to let the craft settle a bit more into the cradle. I also sanded it smooth and let Kid-zilla apply the sealant as I hit the trucks’ frames with Navy grey.

Inching closer…


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A very interesting project I will watch it with interest.
A good example of re purposing/recycling every day objects into models.
I cannot look at things the same way anymore I always have the though “I could use that”

don’t fall into that trap!
or you will end up like me.

junk of every kind - everywhere.
and no more space for a layout.


Job and other activities (to include a nice bit of SCUBA diving last Saturday) delayed progress to a catch-as-can status. Since the last update, the cradle got some filler…

…and everything got decks and a coat of Navy grey.

Today, Kid-zilla and I made a push, after I helped to move along some rocketry projects. This included cutting and drilling the “arms” as well as cutting brass tubing that will house the connecting bots, allow for freer swing, and, in the case of the trucks, minimize or eliminate the any “chewing” as this whole thing pivots. I cut (picture courtesy of Kid-zilla)…

…and he tapped in the tubing.

I really, really hope we can get this thing on the rails next weekend to test it before we begin a final fitting out. Kid-zilla is seeing the end of the project, re-energizing him which has in turn energized me. If this all works out - and he is happy - then this will be worth the detour I took on my 2023 plans!

Updates will follow as required!

Have a Great Week!


GAP, there is no way to participate in this hobby at the rear end of the world’s supply line without that skill! It has been a long time coming for me, but these projects have given my kids the “eye,” though they may choose to apply it in other hobbies.



Kid-zilla has been eager to finish Bullpup

…in order to catch up to his brother in the National Association of Rocketry Training Rocketeers for Experience and Knowledge (NARTREK) “Cadet” program. I had to show him each step once, but he proved a quick learner. Wonder where and how he got those modeling skills?

We decided that the arms that connect the trucks to the cradle should get safety stripes, so, over the weekend, he painted them yellow…

…then bogarted the Valley of the Nap while I was putting away the yellow paint! :angry:

Sunday, I showed him how to mask off the yellow.

He did pretty well after I showed him the ropes. I let him work through his frustration with the imperfectly sticky masking tape! In the results below…

…the smile says everything. Not perfect, but perfectly suitable.

By evening, it was all dry enough to do a test assembly. We set-to with drills, files, and Dremels to fit the brass tubes into cradle and trucks…

…then affixed fender washers to serve as glide plates. Naturally, I had the wrong sized screws to put it all together, buy we were both excited to just see it held together by gravity and friction, so we forged ahead. As the picture below shows, the assembly, even with rock counterweights, sags pretty heavily!

The original plan was to make “baskets” and fill them with stone to trim this beast fore and aft. I think that would be insufficient absent very high baskets, and I may resort to tire something denser like the lead beads from a retired SCUBA weight.

We are both really excited to see the project come this far just as summer vacation is coming to a close. He proudly announced that “This was our hardest project yet!” I was heartened by the enthusiasm, and especially heartened by the use of “our” and not “Dad’s.” We celebrated by bringing the railroad, clearing the table for dinner, and watching trains as the sun went down.

Inching closer to complete!


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I am wondering if the mounts for the bumblebee striped pieces should be a little ahead of center to carry the weight better without the tilting of the trucks. Or some kind of Z shaped arms instead of the straight mounts, but still ahead of center a bit


A z-shape would be outside of my skillset! Mounting the arm forward is a possibility, either by putting another cross-member under the deck or by mounting it to the forward endbeam. I would think adding weight would be the easiest choice to both execute and to fine tune.

I got the right sized screws, so we’ll see what that does to the rig and go from there.



This was our main project today. We have entered a fun part that involves actually running this thing on the track to see if all of our hard work will pay off! We knew from our previous experiments that we were going to have to weight the trucks, so I grabbed a pair of 2# dive weights as Kid-zilla prepped Mack for duty.

Initial runs showed that we had overtightened the arms…

…and that we needed to fix the trucks to their platforms. This required some disassembly…

…followed by CA glue and reassembly. When that was all down, Kid-zilla took a moment to see just how big his creation is!

After derailments, we placed a short flat car between Mack and the rig to see if that would help.

Maybe, but Mack was spinning, so we brought out a helper, Kolea, which Kid-zilla informed me is Mack’s girlfriend (I keep a few cars between them at night, as they are not married! The Triple O is a PG affair!).

Alas! Poor Mack is wired opposite to Kolea, so we had to bring out Mike Bananapeal for the remainder of the trials.

Video: Trials #1
Video: Trials #2

There were a few pinch points, and more revealed themselves when we placed his submarine on the cradle and took it slowly around the tracks.

Frankly, I am surprised it worked that well! Part of the issue is the lack of straightaway to allow the cradle to line with track before it hits the next curve. We can route this rig around that building, luckily, and we can always trim / tie the plants.

So where does that leave us besides arboring? First, as I still need my dive weights, we have to find up to 4# of weight to balance everything. Kid-zilla suggested some sort of box. I am not sure what we would put in that box! Second, we need to add some steps, tie downs, lettering, etc. to bring this to life. Finally, I need to figure out how to open Mack so I can reverse the wires on his motor and let him pull this rig with his girlfriend!

Even if the final project is a “set out” piece, knowing it COULD work will make bringing this over the line worth our time.

Updates as required.


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Eric, looking at the pics, it appears the cradle pivots at both ends of the yellow/black piece from which it is suspended. How does that work?