Services: Scale Beamway

Scale Beamway
The worst part of the Disney model is the oddly shaped beamway. It looks nothing like the prototype and detracts from what is otherwise a pretty good scale model. The good news is it can be corrected. The bad news, of course, it isn't easy.

Getting scale beamway is not that bad, Lowes, Home Depot, and other building supply stores have it. Oh, they call it things like vinyl siding and vinyl molding but what do they know? ;) In reality, vinyl molding makes great beamway, just plane it to the proper thickness, cut it to the proper height, sculpt it to the appropriate contour and it looks very much like concrete beamway! It can be formed into curves and elevation changes, and it even takes a set when formed correctly.

The prototype beam width for straddle beam monorails is usually from 20" to 35", with 26" used for the Walt Disney World system. The beam height for this system is from 48" in the center to 80" at the endpoints. The table below shows some common scale dimensions for the beam.

Scale Width Minimum Height End Height
Prototype 26" 48" 80"
HO (1/87) 0.30" 0.55" 0.92"
N (1/160) 0.163" 0.30" 0.50"

Our N Scale beam measures 5mm wide x 20mm high, not quite to scale but it looks better that way (probably because the model is not quite to scale either). For the Disney model I plan to use 8 mm wide beam which comes out to about 27.4". The beam could be 7.6 mm for exact HO scale but the tires I use are 8 mm wide so that works well.

Scale appearing Disneyland beam can be made by routing a little from the sides of the beam and does not affect the operation of the model.

 

Modifying Disney's monorail is a bit more work. Ok, a *lot* more work. The wedge shaped beamway is a means to allow loose manufacturing tolerances while still guaranteeing the monorail will run decently. The original rubber drive roller system will not work on scale beamway so the drivetrain must be replaced with one that places the drive wheel on top of the beam instead of on the side of the beam.

After having successfully tested several of these "top-drives" I now build (and have sold) WhisperJet, a replacement for the original drive system that uses belt drive to drive from the top of the beam. Some cutting on the lower shell is required but it will not show when the monorail is on the beam.

 

Planing Vinyl Molding Planing vinyl siding to thickness.

As I was demonstrating the RC monorail someone reminded me that the real monorail is powered from metal rails on the side of the beam, and why didn't I do that if I really wanted scale beamway? I had previously looked at that idea and even tried some pieces of code 55 model rail (0.055" tall and wide) glued into grooves cut into the sides of the beam. It seemed like far more work than RC so I dropped the idea. Anyone else want to try it?