Monday, April 30, 2012

25mm Monorail

This past weekend I was able to make considerable progress on a number of projects. The subject of this particular post is a 25mm scale monorail inspired by the Patiala State Monorail Tramway.

Rolling Stock

As mentioned in a previous post, my first inspiration was the RAFM Cyclops land wheeler converted to an armoured draisine as used on European Railways in the 20's and earlier. I had some ideas on this but also needed some regular rolling stock. Digging around the bits box - or bits shelf in my case I came across these cheap HO (1/87) scale north American prototype cars. I bought them and other assorted bits for a couple of dollars at a yard sale.  At 25mm (1/64), they are very close to the 6' width used on the Patiala.

Breaking out the razor saw, filler and epoxy putty results in this:

I am very happy with the gondola and flat car. Though the gondola is of metal and not wood construction, it has that toy like quality of its inspiration.  Key to making these cars was realising that I am making what are effectively terrain pieces and not actual model trains. The wagons will not have functioning wheels underneath just alignment blocks to keep them on the rail. The wheels on the original scale out to 1/16" radius and are not visible from most angles.  I am not entirely happy with the passenger car as it is a little too short for 25mm figures to fit in without bending down their heads. Not very comfortable for my pewter passengers. I will keep it for the moment with the intent of replacing it in the future. I might plate over the windows to turn it into an armoured troop car with firing slits.

Also in shot is the Cyclops in its draisine configuration with the rear wheel well faired over with epoxy. To its left is the remains of an HO locomotive power bogie. This will be reassembled to go under the Cyclops. The actual Patiala locomotive drive wheels can't be seen easily, but that look didn't really work here so I went with something beefier. As of this writing, the epoxy hadn't hardened up (cold in the garage where I do my work) so further conversion is pending. 

A proof of concept shot:

The wheels are spares from the Cyclops kit propped up against the wagons to test the look. When I started this project, I thought that more prototypical wagon wheels would be easily available from the Dollar Store. I went to three different stores thinking I could pick up a couple of cheap plastic farm wagons or stagecoaches but no luck. Cow herding and farming being out of fashion with today's youth apparently. I have written RAFM with a request to get some of their artillery wheels for the project as well as more Cyclops wheels for a VSF/Steampunk Saladin armoured car.


In the shot below is some HO/OO set track that also came with the loco and rolling stock. I measured the amount of tie projecting out from edge of the two rail track, set that as the offset on my scroll saw and ran the sections through. There was a little bounce from the blade action that gave a raggety look to the ties that fits in with hurriedly and cheaply laid rail. A band saw would give a smoother cut. I did not use the set track as I have a box of flex track to play with that gives longer continuous runs and tighter radius curves.

The next shot is the MDF combined railway roadbed and road way with the track line and road edge marked in. These are of course wrong as I discovered once I thought about it. The monorail is "handed" in that the track runs along the left hand edge of the adjoining road. This means that on a right hand curve, the supporting wheel is on the inside edge but on a left hand curve it is on the outside so the radii and placement of the track and road need to be adjusted accordingly. The widths and offsets were calculated from the prototype and the curves are designed so that a 90o curve fits within a 12"x12" block.


Track laying and ballasting up. I stuck the track down with contact cement. Unexpectedly, the glue failed in shear when I was trimming the rail ends so the track needed to be re-glued and pinned. This is not an issue with normal flex track as it has holes in the ties for nails - holes that I had trimmed away earlier. The ballast itself is some very fine sand and dirt I have lying around as I am too cheap  frugal to go buy real ballast. It is wetted down with wet water - water with a couple of drops of soap to break the surface tension - then flooded with dilute PVA medium. The effect was not quite what I was looking for but I will live with it for now (which beats scraping it all off).

The result. There is a lot more work to do especially with the road way. I am going to make up a card form with the road profile cut out to shape the road a little more cleanly before sticking everything down.

To date this is one of those projects that gets better as you go along but will probably not do again.

More to come.

1 comment:

Tony said...

That looks great - very well done for choosing such an original railway system.