pizza Petra Pizza - a 4 square feet HO scale layout

[jimsmodeltrains]

This HO scale micro layout was one of 3 I proposed to be built to replace a large-ish (approx 14x8 feet) modular 'U' shaped freelanced American outline model railroad representative of the area around Dolton, IL. With the possibility of an impending move some time in 2020, I decided that it would be best to minimise the layout moving stress and dismantle the previous modules in favour of some smaller and easier to move modules. The 3 micro layouts were the result, with a possible 2 more easily stored ans set up ultra-micro layouts.

 

 

Layout Description

 

The “Petra Pizza” is a 600mm x 600mm square (approx. 4 square feet) layout, with a single circle of track, with mountainous scenery, and very tight curves (for HO scale) averaging about 11 inches radius. It represents a small quarry branch to a small fictional town called Petra somewhere in Maryland, USA, which is also the location of a quarry which is the main industry served by the branch and the only industry modelled on the layout.

 

 

The curves on the layout are around 11 inches on average (which means there are some parts of the circle tighter than that)! You might be tempted to think this limits the cars and locos that can run on it. Well, it does. But not as much as you might think. As far as motive power, a Bachmann DCC Onboard EMD GP 4 axle loco works ok, and the shorter wheelbase Alco S series switcher also works ok. As far as rollingstock, I have some 22 foot mineral hoppers and 40 foot open hoppers which serve the quarry, some 40 foot MOW cars which run as a tourist train, and some other carefully selected 40 foot cars that can handle the tight curves.

 

 

 

I am hoping to purchase a small Plymouth switcher to operate the branch, as it will look a lot more at home than the longish GP locos I am currently using on it.

 

Operation

 

Operating a layout that is just a circle of track might seem somewhat boring. But I have worked out a relatively interesting way of operating it none the less. A train including some open / mineral hoppers starts off somewhere on the layout away from the stone loader, representing Petra Junction, the place of interchange with a class 1 railroad. The train is started, and makes it’s way up the mountains, passing through many tunnels, for a set number of minutes, then it arrives at the Petra stone loader. At this point the train crew has to align each hopper under the stone loader so they can be loaded. Once all cars are loaded, any extra cars (eg box cars or fuel tankers) are moved to the trackside shed / depot a little way from the stone loader for unloading. Once that is done, the train starts again back to Petra Junction.

 

The operation of the weekly MOW cars as a tourist train is operated in a similar way, starting at the Petra Junction depot, and running to Petra depot up in the mountains. But instead of stopping for each car to be loaded under the Petra stone loader each car has to be stopped in front of the Petra depot.

 

 

[jimsmodeltrains]

Here are some videos I made of construction:

 

Video 1: This video is "proof of concept" - whether a less than 12 inches curve radius would work with the locos and rollingstock I already had.

 

 

Video 2: This video shows scenery building for the layout, and a few extra different locos and cars that can be run on the layout.

 

 

Video 3: This video shows scenery detailing for the layout including painting rock faces and ground, and first round of adding vegetation to the layout. Video also includes footage of a loco and cars running on the layout.

 

 

Video 4: This video shows completed scenery, including extra detailing, and running trains.

 

 

 

[Jeff P]

Great work. If you can, you might want to see if you can find a Bachmann 44 tonner or a 70 tonner. The Western Maryland had a 44 tonner and a short line on the south side of Baltimore had a 70 tonner...it was the locomotive Bachmann used as its prototype for the 70T.

 

Jeff 

[jimsmodeltrains]

14 minutes ago, Jeff P said:

Great work. If you can, you might want to see if you can find a Bachmann 44 tonner or a 70 tonner. The Western Maryland had a 44 tonner and a short line on the south side of Baltimore had a 70 tonner...it was the locomotive Bachmann used as its prototype for the 70T.

 

Jeff 

 

 

Thanks for your comment Jeff.

 

I tried a GE44 and GE70 on the layout, but they seemed to like the sharp curves less than the GP I tried (strange, I know). The GE44 and GE70 developed some very obvious drive train problems as a result of using them on the layout, although they might have had unknown drive train problems before using them on the layout. I managed to fix the drive train problems, but then didn't want to try them on the layout again in case the same thing happened. The GP I tried works ok but has a lot of overhang. I also tried a Bachmann DCC Onboard FT-A loco, which works quite well and doesn't have anywhere near the overhang of the GP. I figure a loco that has no trucks / bogies would work and look better, so am thinking of a Plymouth or something similar. Considering the trains a quite short, a smaller loco would look quite good, I think.

[Jeff P]

If you modeled in O scale...the Plymouth that Atlas put out in the 70's runs a treat and will pull a stump from the ground. Best thing was the center drivers were blind so they are great on tight curves. 

Best,

Jeff 

[d&h]

That looks very impressive. I've "played" with Fleischmann 10" curves using UK stock and it surprised me what worked. I think a lot of it depends on the manufacturing tolerances of individual batches. I had instances of the same model one ran perfectly the other would not take the tight curve at all.

[friscopete]

I have used UK stock down to about 6-7 inches .Naturally you need  0-4-0',perchance a Peckett s at that point , but the  Hornby type couplings were OK , Kadees better .I got  Hon3 Blackstone down to 12  with everything functioning on a quick experimental set up .

[ColinK]

I also recommend 4 wheeled locos, but make sure you turn them round every now and then.  I made a micro layout which was basically a circle of track to a tight radius - so the outside rail is much longer than the inside rail. After a two day exhibition the loco was mechanically wrecked as a result of the outer wheels having to go much further than the inner ones. I should have turned it round  every hour or so.

[jimsmodeltrains]

8 hours ago, ColinK said:

I also recommend 4 wheeled locos, but make sure you turn them round every now and then.  I made a micro layout which was basically a circle of track to a tight radius - so the outside rail is much longer than the inside rail. After a two day exhibition the loco was mechanically wrecked as a result of the outer wheels having to go much further than the inner ones. I should have turned it round  every hour or so.

 

I think that's good advice on turning the loco from time to time! I must remember that. The GP / SW's I have used on the layout seem to be ok, but I think the tight curves are really at the limit of the smallest radius they can handle.

[jimsmodeltrains]

15 hours ago, friscopete said:

I have used UK stock down to about 6-7 inches .Naturally you need  0-4-0',perchance a Peckett s at that point , but the  Hornby type couplings were OK , Kadees better .I got  Hon3 Blackstone down to 12  with everything functioning on a quick experimental set up .

 

The Ruston & Hornsby 48DS I have works a treat on the tight radiuses on my Petra layout with the Hornby couplings. But then it's a really short loco.

[jimsmodeltrains]

400mm legs added under the Petra Pizza layout so I can add another pizza (or maybe an inglenook or something like the square foot estate but bigger) underneath. The round thing on the bottom baseboard is a lazy susan 'bearing plate', which will be added under the bottom baseboard so I can spin the layouts around for different views.

 

[Neil]

It's possible to do something like this to UK outline. Many years ago I built a OO gauge pizza in the same footprint. Track radius was about ten inches.

 

 

More about it here.

[Keith Addenbrooke]

6 hours ago, jimsmodeltrains said:

400mm legs added under the Petra Pizza layout so I can add another pizza (or maybe an inglenook or something like the square foot estate but bigger) underneath. The round thing on the bottom baseboard is a lazy susan 'bearing plate', which will be added under the bottom baseboard so I can spin the layouts around for different views.

 

Hi Jim.  A pure Inglenook in HO would be quite a challenge in a 2’ space, once you’ve deducted the dimensions of the two switches and allowed for a loco length, there’s very little space left - you know all this already of course.  A version of Carl Arendt’s Square Foot Estate however would be ideal (loads of space for that).

 

Have your tried testing the double height layout on the lazy Susan - as you get higher, might a bit of a wobble appear?
 

If not, why stop at two levels...? (sorry)

Edited June 26, 2020 by Keith Addenbrooke
(either I can’t type, or I can’t read what I type...)

[Dunvegan]

Alzheimers  rear it ugly head .The Petra Pizza looks like something I can do these days

[jimsmodeltrains]

On 26/06/2020 at 22:00, Keith Addenbrooke said:

A pure Inglenook in HO would be quite a challenge in a 2’ space, once you’ve deducted the dimensions of the two switches and allowed for a loco length, there’s very little space left - you know all this already of course.  A version of Carl Arendt’s Square Foot Estate however would be ideal (loads of space for that).

 

Have your tried testing the double height layout on the lazy Susan - as you get higher, might a bit of a wobble appear?

 

Hi Keith.

 

I am probably leaning more towards the square foot estate than an inglenook, and it would probably be standard HO equipment (I tend towards using standard / non-modified / non-customised equipment). I might try an inglenook if I decide to go for N scale or HOn though.

 

I haven't tested the lazy susan under the double height layout in the picture yet. The layout base is about twice the width of the diameter of the lazy susan base, and the lazy susan base is only about 5mm high. I have heard of multi-storey lazy susans being used for foods stuff and some of them could be about as high as the layout in the picture, but then the weight and 'overhang' might not have been as great as it will be for how I am planning to use it.

 

I think it will probably be ok, but thanks for informing about a possible wobble.

[jimsmodeltrains]

On 26/06/2020 at 17:44, Neil said:

More about it here.

 

Hi Neil.

Had a look at the webpage at the link. Looks like a good little layout you had there. I think If I decide on a Pizza, I will probably go for a couple of short operational sidings rather than purely decorative ones. I'm not sure whether I will go for British outline yet although British outline models certainly have the advantage of being quite short and able to handle tighter curves than American models might. Your layout at the link does present some interesting ideas and possibilities.

[jimsmodeltrains]

On 26/06/2020 at 22:00, Keith Addenbrooke said:

Have your tried testing the double height layout on the lazy Susan - as you get higher, might a bit of a wobble appear?

 

Hi Keith.

 

I attached the lazy susan base under the double stacked layout configuration. There is a very slight wobble, but it's hardly noticable and so I don't think it's anything for me to worry about.

 

I think the low amount of wobble might be attributable to the fact that the Petra Pizza on top is quite light. The frame is the heaviest part of the layout, and it's basically an 'x' under the baseboard, with 'fairly thin plywood around the edges, and light wooden blocks in the corners to fasten the outside frame to. Which is why the Petra will be on top as the baseboard on the bottom has a more traditional and heavier pine frame around the edge.

[Keith Addenbrooke]

9 hours ago, jimsmodeltrains said:

 

Hi Neil.

Had a look at the webpage at the link. Looks like a good little layout you had there. I think If I decide on a Pizza, I will probably go for a couple of short operational sidings rather than purely decorative ones. I'm not sure whether I will go for British outline yet although British outline models certainly have the advantage of being quite short and able to handle tighter curves than American models might. Your layout at the link does present some interesting ideas and possibilities.

One potential disadvantage using UK outline stock on very tight curves is the increased risk of buffer locking.  I understand this is the reason for the traditional large tension-lock couplings: more modern stock has dispensed with these.  
 

Buffer locking isn’t an issue with US outline stock, but I’d imagine there could be a problem if you had a train mixing body mounted and truck (bogie) mounted couplers?  Just a thought.

[jimsmodeltrains]

10 hours ago, Keith Addenbrooke said:

One potential disadvantage using UK outline stock on very tight curves is the increased risk of buffer locking.  I understand this is the reason for the traditional large tension-lock couplings: more modern stock has dispensed with these.  
 

Buffer locking isn’t an issue with US outline stock, but I’d imagine there could be a problem if you had a train mixing body mounted and truck (bogie) mounted couplers?  Just a thought.

 

Hi Keith.

 

The short 4 wheel English rollingstock with a Ruston & Hornsby 48DS I tried on the Petra Pizza worked ok with the newer tension lock couplings provided on new rollingstock these days. The American 4 axle open hoppers I use on the layout have bogie mounted couplers, but when I have cars with body mounted couplers they mostly work ok. Thats the rollingstock I have, which is varying brands and quality.

 

But I do sometimes need a caboose or other body mounted car between the loco and the cars with bogie mounted couplings! Probably because of the overhang on the GP 4 axle loco and the resulting coupler angle which seem to force the bogies on the next car of the track.

[Keith Addenbrooke]

On 11/06/2020 at 07:40, jimsmodeltrains said:

 

 

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5 minutes ago, jimsmodeltrains said:

But I do sometimes need a caboose or other body mounted car between the loco and the cars with bogie mounted couplings! Probably because of the overhang on the GP 4 axle loco and the resulting coupler angle which seem to force the bogies on the next car of the track.

Hi Jim, I went back and had a look at the opening photos - I think I can see what you mean about the GP!  Thinking about it, I guess the trucks are a bit further in from each end than on the caboose or shortie 40’ hoppers so it makes sense.  
 

At least you’re not laying a double track line with cars sideswiping each other (some years ago I worked out with Carl Arendt that it could be done on a micro-layout, at least in theory...)
 

 

[jimsmodeltrains]

Recently I started creating some name boards using MDF lettering for my various micro layouts.

 

Here is the one I made for the Petra Micro Pizza layout.

 

 

The EMD / GM FT has a lot less overhang at the front and back than a GP3x / GP4x!

[jimsmodeltrains]

A YouTube video I made of a train being 'operated' on the layout this afternoon.

 

 

 

[jimsmodeltrains]

A petite Plymouth for the HO scale Petra Pizza micro layout means no more large 4 axle diesels locos need to be used for motive power.

 

For some time now I have wanted to find some motive power for the Petra Pizza micro layout that better suits the short trains sharp radius curves on it. I had been using GPs and FT-A which are somewhat over powered for the short trains, and the sharp curves caused a lot of overhang, and required a caboose between the loco and the other cars. Recently I ordered and received a Walthers Plymouth ML-8 4 wheel switcher (or is it a rail tractor?)

 

 

It is not much bigger than the X200 class NSWGR rail tractor I received a week or so ago, so it could probably be classed as a rail tractor. It would haul similar tonnages as the X200. I ordered the Plymouth through eBay, and I thought that it would be DCC equipped. But alas, I mis-read the listing – it is able to be fitted with a DCC decoder, but is not DCC equipped. Not to worry.

 

Above: ML-8 at the Petra depot.

 

I have a number of locos that I no longer use, for various reasons. One of them is a Bachmann DCC equipped GE 70 tonner, which has a dodgy drive train which I haven’t been able to fix. So I decided to butcher that GE 70 tonner and remove the decoder and do what I did with the Tropical Pizza layout: I wired the decoder from the GE 70 tonner into the Petra Pizza layout.

 

Above: ML-8 with 3 open hoppers loaded with stone from the Petra quarry loader

 

This means that I can run anything on the Petra Pizza layout (that will get around the sharp curves) whether DC or DCC (any DCC equipped loco used on the layout will just it is being controlled by a DC system).

 

Above: ML-8 with short passenger train of MOW cars.

 

After a bit of testing, and experimenting with trains, I found that the Plymouth ML-8 will haul about 4 heavily weighted 33 foot open hoppers, or a few passenger or box cars without any problems. And it looks great on the layout going around those sharp curves!

[jimsmodeltrains]

A recent video I uploaded to YouTube featuring an IDR NSWGR X200 and Walthers Plymouth ML-8 rail tractors on the layout.

 

Regards, James

[jimsmodeltrains]

Passenger depot improvements for the HO scale Petra Pizza micro layout.

 

Since I built the Petra Pizza layout, the Petra Depot area was a fairly basic ground level gravel area with a shed.

 

 

In the last few weeks I had a growing desire to do something to improve the scene. And in the last few days that desire translated into action. The first thing I had to do was remove the existing depot scene down to the baseboard including removing most of the ballast along the outside edge of the track.

 

 

I decided that I would raise the platform using some foam core. This meant I had to cut a piece of form core to fit into the corner where the old depot area was – not an easy task as the area had unusually tight radius track that isn’t a constant radius. I cut a triangle section of foam core, and then slowly trim off the foam core near where it would be next to the curve until I had the right shape. Eventually I completed this so the platform was the required shape. I then added a platform facing / retaining wall made of coffee stirrers and matchsticks along the edge near the track.

 

 

Next I covered the new foam core platform with PVA wood glue, and sprinkled a local sand mixture on it. I then placed the shed, a fuel tank, some foliage on it. At this point in the project, with the glue still wet it looked like this.

 

 

The last thing to do was to add some extra scenic detail to blend the new depot into the surrounding area including two stetson wearing locals, and ballast the track that had been un-ballasted for the first step in the improvement.

 

 

 

There is still a little more to do though. I want to add some decorative fencing on the platform area like what is often seen on passenger stations / depots to make it look a bit more pleasant to the eyes. But as it is now, it is ready to receive trains of 1:87 scale railfans and mountain dwellers.

 

While I was doing this redevelopment, I realised I could also improve some other parts of the Petra Pizza layout to include a freight platform and / or bulk transload area which will make operation a bit more interesting, but that’s a post for another day.

 

Regards, James

 

(From: https://www.jimsmodeltrains.ws/2021/09/22/better-depot-for-petra/ ).