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Space Monorail


The Next Chapter

Many thanks to all our 500 supporters!  We got half way to the 1000-supporter stage point.  This project will return and continue with Powered-Up trains, again using the same pieces as a train set.  I chose a Blacktron prototype for the first PU experimental train.  It can go round the stress-free curves that have a radius as small as 24M, tighter than those of the original 1990s monorail.  I would still like to improve the drive train for it but it does manage to turn well.

The monorail will stay versatile, with liveries of Classic Space, Blacktron, Futuron and M-Tron.  In the spirit of the original theme products, the Blacktron faction will be able to steal modules from the others!

The monorail system works with the new Powered-Up pieces.  The battery-carrying frame is extended by 2M and the geometry still works.

I am encouraged that a few more people are trying this style of monorail system.  Please keep sharing and spreading the word, and look out for the return of this project, to support it.  I will update the Classic Space train with the Powered-Up pieces and add to the Blacktron train.

See you again soon!  If everyone brings a friend then we will pass 1000 next time.


Variations on a Crater Theme

Thank you to another fifty new supporters!  We have now passed 220.

Since my initial tests with the new bricks from last time, and success in creating stress-free curves, I have been experimenting with the train chassis.  I now have a chassis that will power round the tight curves.  After some more work on reliability and weight distribution I'll make another video.  So far the new chassis has a Blacktron colour scheme; I am aiming to recreate a few of the Space liveries to keep the monorail as versatile as possible.  This would include Classic Space, Blacktron, Futuron and M-Tron.

In the meantime, a further purpose of the Space Monorail set is to assist in the revival of Classic Space building.  To that end I have digitised the crater plate, making it from a standard flat plate with some plates and slopes built on it.  This also allows the same mix of bricks to be used to create straights and other shapes of crater plates to add to the standard curved quarter-crater.  The pictures show a standard crater shape next to a straight using the same bricks.  Four times this arrangement would show as a 48x48 crater within a 96x96 crater.  This is a half-way-house between standard plates and bespoke landscaping.  It would be good for the set to encourage enthusiasts by bridging that gap.  This is in line with the core versatility of the LEGO system.

I have also adapted my new monorail train chassis to run on the new roller-coaster track.  So far it will stay on a 90-degree curve most of the time and will climb and descend the 3-brick-high slope.  Whilst this is useful for running trains on the roller-coaster track system, they would not run as fast as on the 2-wide ride-on-top track, so the roller-coaster track is another system alongside the monorail on a Space layout, not a replacement for it.  The roller-coaster track is dependent on bespoke pieces, so its switching tracks consist of a traverser with straight sections sliding sideways.  I will continue to use points in the monorail system, whether or not a traverser is included.  Masao Hidaka has made a traverser for this monorail system.

Since we have seen a bit more of the new train sets with Power Functions and a new Bluetooth control system, this monorail system would work with the new pieces.  The battery-carrying frame could be extended; this extension would not make it any longer than the motor part of the train so the geometry would still work.

Please keep sharing and spreading the word, and look out for more updates on different aspects of the project.


Completely Stress-Free!

Thank you to another twenty new supporters!

Now that my brick order has arrived from LEGO Shop at Home, I have built some permanent curves and some movable curves at the tight and compact curve radii.

The permanent curves use similar techniques to the original wide-radius curves but with parts substitutions.  The new 1x2 plate with rounded ends (in black) allows stress-free connections between the 2x2 modules when alternated with ordinary 1x2 plates (in red).  1x1 round dots provide space for the plates to turn.  2x2 round plates allow the same stress-free coexistence in between the ordinary 2x2 plates.

The original wide-radius curves relied upon the tolerances of two 1x2 plates turning in the same space.  The wider compact permanent curve, with a radius of 19M, uses a single tolerance just to limit the curvature.  It holds its shape independently so it is practically stress-free.  In the set it would use dots instead in order to be theoretically stress-free too, but it shows a useful practical radius limit that keeps the curved shape well.  The tight curve at 12M radius goes the whole way with dots and is completely stress-free but this is more difficult for the trains to go round smoothly.  I would recommend a tightest radius of around 18M for smooth running.  Of course any radius wider than these minimum sizes is possible.  My default sizes are 48M and 10M intervals when in parallel with other tracks, so 38M, 28M and 18M.  Any radius from 12M to infinity may be used for single tracks, with 10M differences for multiple tracks.

The movable curves are based on the point and junction technology, using coupling plates with no stress.  These have radii of 12M and 18M.  The 12M curve sticks out by 1M at one end but a half-circle at the small size could be made as one piece without and extra 1M in the middle.  For a given curve they have fewer, sharper turns per module.  Whilst the larger of the two curves uses longer modules, this could be changed to use more of the smaller modules for smoother running, as long as the curve could keep its shape as trains ran over it.

So we are now completely stress-free in curves for the purposes of a Space Monorail set.  We can also choose to use tolerances as limits in MOCs for any wider radii than the stress-free minimum.

Also shown is a motor bogie arrangement that is able to run over the 19M curve well enough.  I have further developments in the pipeline so that the drive train will adapt to the greater turning of the bogies.  The turning is well within the capabilities of a universal joint and does not exceed 45 degrees for the 19M radius curve.  My key with the train design is to avoid torque-steer so there will be no vertical axles through the bogie pivots.  After the train is built to power itself over the tight curves I will do some reliability testing and then fit it with the appropriate Space liveries.

I'm really pleased with the result of the curve experiments because they have achieved curves tighter than my 32-40M target.  They can go tighter than the standard L-gauge railway track, narrow-gauge (Indy mine) track and the original monorail track and remain stress-free.  This gives flexibility to the set design.  Whilst it is not necessary to go as tight as the roller-coaster track, 12M stress free has been demonstrated.

We need to get more LEGO Monorail and Space fans involved so please keep sharing and spreading the word, and look out for more updates on different aspects of the project.


Stress-Free Progress

Thank you everyone for your support; we have now passed 150.

I have continued with the stress-free curve experiments in two families.

  1. Like the picture in the first update but smaller.  These curves use coupling plates.  They are robust to the weight of the train and can have a minimum radius of just 12 modules.
  2. Like the wider curves in the original project but with some piece substitutions.  Verification of robustness is waiting for parts but it is possible to make a tight curve with a radius as small as 12 modules.

I have tested how smooth a train bogie would be going round these tight curves.  The coupling plate type works quite well, even at the smallest radius.  The original type will depend on the piece substitutions.

The next trick is to make the train with bogies that can turn by 45 degrees for the tightest curves.  I have a first prototype of that but it would be larger than I'd like.  My prototype avoids "torque steer" by not having the drive shaft going through the bogie pivot.  Torque steer would have caused the bogie guide rollers to catch on the curves, in the gaps between modules, rather than the bogie being able to find its own way smoothly.  The requirement to avoid torque steer sits alongside the need for simplicity in the drive train and the need to stick to legal building methods.

In the end I may decide that 32-40 modules is a tight-enough radius, like the previous monorail or the standard train curves.  That would be fine in a set.  Coupling plates are still sufficiently basic to meet the obsolescence objective; they have been produced for seveal decades now.  So we have two methods for making stress-free, legal curves at various radii from very large to very small.

Please keep sharing and spreading the word.  We need to find all the LEGO Monorail enthusiasts.

The new LEGO Roller-Coaster sets look like fun but they are quite different from the objective of a Monorail.  The monorail has powered trains where a roller-coaster has power only for lifts, guide wheels and station departures.  There is room for both.  It will be interesting to see for how many years the Roller-Coaster sets and track pieces are produced.  The track pieces are less-bespoke than the previous monorail but the carriage bases are bespoke.  This monorail would take a couple of years from now to produce, so it would not clash in the product range.

We just need your support to get it made.


100 Supporters and Stress-Free Curves

100 Supporters!  Thank you everyone.

I had hoped this first milestone would have come sooner, as we have a lot of work to do to convince the LEGO company that enough people want another monorail set.

Some people have suggested that the curves in the set should use an alternative design in order to be completely stress-free and suitable for a set.  Thanks for the heads-up.  Stress-free curves can be made in a few different ways.  This picture shows how the pieces used in my switch point and junction prototypes can be used to make a stress-free curve with a radius of 18.5 modules.  This is tighter than the system would need, and the train design would need to evolve to go round it, but it is one solution that is available immediately.

I have other solutions in mind too.  I have ordered some parts including round plates and some of a new 2018 piece, a 1x2 plate with rounded ends, to make a more flexible version of the curves featured in the videos.  A simple parts substitution would be suitable, and some of the original pieces can remain in each curved section.  I anticipate that the updated curves would have a range of stress-free flexibility beyond what is needed, so after building a curved section I would form the curve evenly around a pre-existing curved shape, such as curved railway track, or maybe the mine track if a tighter curve is possible and desirable.

It is normal practice in engineering for several solutions to be tried and the best ones selected.  All the curve solutions will stick to basic pieces to avoid potential obsolescence; this is one of the top-level requirements of the project.  I will post more updates including the evaluation of different curve prototypes; the parts I've ordered would let me try a few different configurations.  I see a radius of 40M or less as an advantage in fitting a track circuit in a reasonable space, like the railway track.  The advantage of a smaller curve radius is both for a set as it fits in the home, and for exhibition layouts, where the layout size is limited by the size of the car used to transport it.  If the tighter radius needs the trains to evolve then that's great; I will enjoy the challenge and it will be fun to post more updates about the development.  There may be a year to get to 1000 supporters but I would like to get there a lot sooner because the further milestones are more challenging.

As you can see, I'm quite happy to develop the project to overcome any issues and ensure that the technology is good for a system that can last.

Please keep on sharing and spreading the word.  Be part of the Classic Space and Monorail revival!

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