Brickthus

🙂OK, here's the technical development of the curves. My curves started with these prototypes in 2012, with the default being a 5-plate sandwich comprising a top layer of 2-wide tiles, layers 1&3 of 2x2 plates and layers 2&4 of 1x2 plates. (these might be larger higher up the thread) In the original, the 2x2s were all square and the 1x2s all oblong. All track pieces keep layers 2, 3 & 4 for 1 stud at each end for a 1x2 brick with 2 holes, using 2 black pegs to connect the next piece. That means layers 2&4 have a 1x1 plate at each end and layer 3 has a 1x2 plate at each end, inset 1 stud from the ends. It takes 19 2x2 modules to make a 1/8 curve of 48M radius, which is the minimum radius without unreasonable stress. This still left some people complaining! Along with 48M, wider curves would stay in place at 58M (23 modules), 68M (27 modules) or 78M (31 modules), so this could form a quad-track round a corner. 58M and 68M also form a double-track helix to gain height. This is complemented by straight spans of 64M to enter and leave the helix. The helix pic shows a different colour of 1x2 bricks with holes. So when people complained on my previous Space Monorail project on LEGO Ideas, I set about solving the tighter-curve problem. The early updates (April 2018) were variants using the 2x3 coupling plates, firstly a 19M radius based on pointwork experiments Then more overlap of the coupling plates to go tighter, as small as 12M radius. But, even having used bogie trains from an early stage, the problems are the evenness and rigidity of the curves and making a train go round them. It was at this time that the LEGO roller-coater track began to appear, so a fairly tight radius was useful for smaller sets. However, an early motorised vehicle I saw was not as compact as a monorail one. The real objective in systemising the track was to be able to recreate the previous monorail sets in function and scale. Then a breakthrough in May 2018 was using the 1x2 plates with rounded ends. With an even pattern of square and round 2x2 modules this made a 19M radius. Using a 2x3 module allowed a 12M radius. These are the minimum stress-free radii for the system. These use black 1x2 plates with rounded ends alternating with red or dark grey oblong 1x2s. So the key after finding the minimum was to find useful sizes for a layout and to make trains go round them. For the Blacktron layout, exhibited in 2025, 24M and 34M make good double track: The 24M curve uses a regular pattern of square and round modules. The 34M curve uses a regular pattern of 2x4 oblong and 2x2 round modules; the 2x2 squares at the end form a 2x4 oblong with the next piece. All of these smaller radius curves are made as 90 degree curves, compared to the 45 degree curves of the previous 48M and larger radii. A bespoke double bend with smaller angles is possible but it is easiest to put the joint where a connection to the next piece can be supported easily. Having made and tested curves in a good range, this opened the possibility of making a 28M radius to replicate the radius in the original sets. As a development from the 24M curve, the 28M curve adds a pair of 2x2 modules (11 square + 10 round), then makes the 4th and 8th modules 2x3. So in this system we have oblong modules of 2x2, 2x3, 2x4 or as long as necessary, and a round module of 2x2. The round module comprises round plates on layers 1 and 3, a round tile on layer 5 and two of the four 1x2 plates on layers 2 and 4, connecting to adjacent oblong modules, have rounded ends. These modules are interleaved to make useful patterns for whatever radius or track formation is needed. A hill (see my previous post) uses sections of 24M radius curve at either end, with the track on its side, using some SNOT pieces. Clip plates and tubing hold the shape, still stress-free and with similar profile to the original hills, rising by 10 bricks in 64M length. Built as a single piece and the middle stanchion uses coupling plates and is attached permanently. Of course all these curves use quite a few pieces so part orders in the hundreds are to be expected. My first order was for 5000 2x2 tiles, 10000 2x2 plates AND 20000 1x2 plates! That would make 45 metres of the wider curves. I have since ordered 2x2 round plates and 1x2 plates with rounded ends by the thousand. But the trend in LEGO sets for adults is for more smaller pieces, so this fits well enough! The reward of a completed curve comes in about 20 minutes. I can make 2 in that time. I'll save the trains development for another post! 😄 Mark

OK, sorry!

My latest project has a few more details. Yes, it is a system of 1-wheel bogies with carriages suspended between them. I've used those since 2014 https://www.brickshelf.com/cgi-bin/gallery.php?i=6276761 - Traction was upgraded from half-bushes with tyres to Creator wheels. - Small Technic pieces make up the bogie with the wheel on axle and 2 pivot points, Vertical rigid axle mounts in the middle allow more structure to make more support to attach the motor car. - Lots of 1x2x0.5 ++ joints, 4 1x2 toggle joints and 2 1x3 toggle joints with central round hole, then a 2x2x2 bracket at either end (sub with 2 1x2 bricks with cross hole for the cab). The monorail system is finally ready to replicate set 6990 as the next Classic Space revival set, following on from 10497 and 10355! - The use of small, available pieces for track, trains and canopies mean it could be sustained from PaB online far beyond the shelf life of a set. https://ideas.lego.com/product-ideas/3b2e5ca7-13c5-4dbe-8c4d-cb9d22b40f93 The motor drives from a train motor have to reach the two bogies at either end. This needs 2 chain drives and a variable-angle bevel drive, making the best of the double-bevel gears! - The first chain drive is 16:16 from the motor to a point above the pivot point. - The variable-angle bevel drive is 12:20 across the pivot point, supported above and below. - The second chain drive is 12:24 down to the wheel axle. - Driving 2 wheels means there is enough traction to climb hills. A 2-motor train (easier with PF) can pull more wagons with the maxim that half the wheels in a train are powered. It was ingenious of you to run on the 12V conductor rails with a radius of 40M, less than the 48M of the standard "wall of 2s" with oblong 1x2 plates but with no stress. But now curves using the 1x2s with rounded ends can go as tight at 19M radius. My previous post of the Blacktron layout used 24M and 34M radii, which make good double-track. Now the 28M radius of 6990 is replicated for the project so that all track pieces can do what the originals do. No need for start/stop rails though, as it's PF/PU compatible. - Straights can be any length but most are 16M, 32M, 48M, or 64M to enter or leave a helix. - Hills rise 10 bricks in 64M like the original. Built as 1 piece with attached middle stanchion for rigidity. Stanchions use vertical axles for strength. - The upgraded 6990 station has train-over-train, which was a feature of 6399 Airport Shuttle. So the question now is whether there are 10000 people in the world who would like 6990 to be revived! Many have their doubts but it depends on whether the community grabs hold of the idea. Out of 850 supporters I've had 400 people save the project so far so there is some real depth of interest. I don't know how to make it go viral though. It's all over Facebook and LinkedIn, and even Bluesky, but is there anywhere else that LEGO Monorail enthusiasts hang out? Mark

Well the LEGO innovation portal came and went! It has taken another 8 years but at last my new monorail is ready to replicate set 6990, which seems an appropriate revival set to follow 10497 and 10355. https://ideas.lego.com/product-ideas/3b2e5ca7-13c5-4dbe-8c4d-cb9d22b40f93 I've proven the system with tight, stress-free curves at shows over the last 2 years. It runs a bit faster than the original at maximum speed and longer 2-motor trains can pull more wagons. This year I developed similar stress-free hills and small-piece canopies. Everything uses small, available pieces and the same electric pieces as a train set, so the parts outlay for TLG would be very little. It would be sustainable from PaB online so there is no need for extra track packs and this is as low as the obsolescence can go. I hope to be exhibiting it again on October 10-11 in Swindon, UK. Mark

Then this one may interest you, a small-piece remake of 6990 Futuron Monorail. https://ideas.lego.com/product-ideas/3b2e5ca7-13c5-4dbe-8c4d-cb9d22b40f93 TLG said they would never make more of the original system so the idea is that this new system, proven at exhibitions, is sustainable from PaB online, including the track, trains and canopies. Bring back LEGO Monorail for ever! For future shows I might incorporate a couple of 21362 Mineral Collection for Space mining operations. Last year I used some yellow/blue 5-wide balls from 21358 Minifigure Vending Machine for a pneumatic robot to manipulate.

Futuron Monorail set 6990 is a "Holy Grail" set for many people, the definitive first set in a system that spawned the Airport Shuttle 6399 and Unitron 6991 sets as well as two track packs. Over the last 14 years I have been developing a new monorail system. It branched from the Hidaka monorail, which models the Osaka monorail, in 2012; mine has a few important differences. - A plate sandwich for the track, allowing a 64M straight span, instead of using deeper bricks. This used my experience of building a railway fiddle yard with a station on top. - Trains with bogies, powered by a standard train motor, PF/PU compatible, instead of multi-wheel rigid chassis vehicles. While there is a LEGO train set, it could support this with the same electrical pieces. The trains were designed for tighter curves from the start. - Tight curves with no stress, using plates with rounded ends. Minimum radius ~20M but 24M, the original 28M and 34M are useful sizes; 24M/34M make good double track. - Hills using a similar technique to the curves. For the last 2 years I have been proving the system by exhibiting it in the UK in the Blacktron livery, using models and parts from 6x 10355 Blacktron Renegade; it runs well all day so the system is mature enough. This shows a short train on the inner track and a longer, 2-motor train on the outer track. The larger structures are built with Technic panels. This year I have developed the trans-blue canopies and hill tracks to enable a remake of 6990 as a set on LEGO Ideas. Whilst TLG had stated that they would not make more of the original monorail system, my design deliberately uses small, available pieces, enabling the new system to be sustained from Pick-a-Brick online far beyond the shelf life of a set. That means there is plenty of time to break track length records and build large layouts. It also gives it the maximum opportunity to allay TLG's concerns (there is very little outlay in parts development, even less than the roller-coaster track sets) and enable a remake of 6990 to be the next Classic Space revival set, following 10497 and 10355. This is close to the original box picture of 6990. I have deliberately recreated all the functions: - The power plant canopies are a bit larger, using available octagonal plates as the 10x10 with cut-out was obsolete. - The station canopy is doubled and adopts the larger size. - Both canopies are made from small pieces, including available trans-blue pieces. - The power plant and station both move like the originals, perhaps with slight improvement. - The station now has two levels, train-over-train, which is a feature adopted from 6399 Airport Shuttle (useful at exhibitions too). - The train has flashing lights in a different place, using pulleys with filters. - The train carries an original container but could carry a wider one. - I opted for SNOT lettering rather than stickers for the "9V" sides on the battery car; those panels are easily removable for battery changes. I expect that TLG would make a few changes anyway, but I hope for a few things: - Futuron livery torsos. - A few recolours, perhaps the cab covers and a 1x1 round plate with hole in trans-blue. Computer roof bricks and radar dish revival in white. If you would like a return of the LEGO Monorail system then please would you support the product on LEGO Ideas: https://ideas.lego.com/product-ideas/3b2e5ca7-13c5-4dbe-8c4d-cb9d22b40f93 ❤️ More pictures accompany the project. Whether or not a future monorail set would be a remake of 6990, 6399 or 6991, can we show TLG that there is plenty of support for monorail? I intend to build more; I have Futuron and Blacktron already but plan to build Classic Space and M-Tron. A City-based one may follow. Please see at least 4 monorail videos at https://www.youtube.com/@brickthus/videos Development pictures at https://www.brickshelf.com/cgi-bin/gallery.php?f=517847 Best wishes, Mark (aka Brickthus)

Thanks, you have understood the idea of it. After doing some obsolescence studies at work 25 years ago, ringing up suppliers and asking "can I still get these parts?", and then seeing how the selection of pieces on Pick-a-Brick online varies, with many parts specific to sets being discontinued after that set ends its shelf life, I sought to use pieces that were most common. This was already a feature of the track curves, with the taller Hidaka design and my own plate sandwich design being based on 2x2 sections. The next trick was to recreate the tighter curves like the original 6990 track. In my previous "Space Monorail" project I had jus the wider curved and there was the complaint of "brick stress" using the "wall of 2s" technique. The solution for me was to use the 1x2 plates with rounded ends but it's not as simple as that because if you use only those the track will lose form completely; it would have to be formed around something and would then change shape as trains ran around it, applying forces as they did so. So the knack was to alternate the oblong and rounded-end 1x2 plates in the right pattern to achieve various curvatures without stress. As it happens, the 1x2 plates with rounded ends are relatively new but we see them in so many sets that they have quickly become a core piece, available in many colours and hence most likely to be continuously available on PaB online. That was key to choosing them. Along with some round plates and tiles with similar good availability, this means the curves as well as straights are made form always-available parts. That meant track extension is almost sorted, with no need for a "track pack" set because LEGO Ideas sets have to be just one set. So production requirements for the track should be OK; it's just a matter of how long it takes to build each curve, but adult sets have more smaller pieces and the reward of a completed pair of curves can arrive in 20 minutes. I could say the same for the canopies; the Technic joints and smaller pieces are common and the trans-blue pieces are those that have been continuously available in trans-blue despite that colour being less-common than other trans colours. There's a bit of trickery owing to the relative sizes and clutch power of a 1x1 plate with or without hole in the various Technic joint holes; I was careful to stick to "legal moves" but it means using some 2M rod pieces where I have 1x1s with holes either side of a joint with 2 axles. The train using the electric pieces from a train set makes sense as those can support each other, even if the system develops. It's a good train motor and should continue for a while yet, even if the plug changes again! The other train parts are mostly common. Small Technic pieces and the available canopy, which I hope might be varied in colour; it was in trans-yellow for Blacktron Renegade 10355 but I had to get trans-clear ones for others as a trans-blue one does not exist. I understand that there is a nominal quota of 4 recolours of pieces for a LEGO Ideas set. Another one I'd like is a trans-blue 1x1 round plate with hole. And I know TLG would vary the design anyway; I just wanted to make it as easy for them as possible with the principle of small, available pieces. 20 minutes for a pair of curves (2x 115 pieces for the smallest) is probably a good enough reward for adult builders, compared to some other kits that I have found very tedious! Then the modularity and varying which bit is built next can help. Even 6990 builds two almost-identical containers at different points in the instructions, just with different tools inside. The track for the set is 4 curves 28M, 2 hills 64M, 1 straight 48M, 1 straight 32M, 1 straight 16M and the lower track for the station, for which I used a 24M curve and a special-length straight of 36M as that is now in the first test of my next exhibition layout; the special length helps align the Train-over-Train of the station with the double-track formation of 24M and 34M curves for the show. I had to stick to the original 6990 amount of track except for the extension suggestion but it is a very customisable system as well as fitting a grid easily. I certainly don't expect a kit of 20000 1x2 plates, 10000 2x2 plates and 5000 2x2 tiles, which is what I bought originally! 😂 That would make 45 metres of curved track. So in the obsolescence strategy I was already hedging by making a "lifetime buy"! I have since added 1x2 plates with rounded ends 1000 at a time for a reasonable number of curved pieces. It may be a little while before I exhibit a larger layout but 6ft x 2'6" is enough work for now, including some public interaction. We're hoping to show at the Great Western Brick Show at the STEAM Museum in Swindon, UK on 10th-11th October. I know there is also a tedium risk with the canopies, building 4 lots of 2x sections of trans-blue pieces to fit the frame. But it's less tedious and quicker to the reward than some sets I've built! The fiddly bit might be the trains. 4 loops of chain. I have experimented with belt drives but those are not as good. The bogies use quite a few small pieces but the design is necessary to get round the tight curves. Someone remarked that the video showed the train going a bit too fast! That has to be a good thing. A bit spare for a longer train, or for when the batteries weaken. But the sustainability of the small pieces is the key to longevity and viability as a system. One can only hope for no more obsolescence but planning helps. Mark

A Futuron Monorail Icons set would have to be up to date, using available pieces rather than the large bespoke pieces of the 1990s. I have been developing a new system for 14 years and it is finally ready to recreate set 6990. Viola! The track, train and canopies are all made from small, available pieces, 3000 for the set. The largest are the available stanchions and a standard train motor. PF/PU compatible, PU in the set, using the same electrical pieces as a train set. I use a PF LiPo battery for exhibitions. An earlier train ran 3km on one charge of the battery. The small pieces mean it can be supported from Pick-a-Brick online, far beyond the shelf life of a set. Track records may tumble! Please log into LEGO Ideas and support the project https://ideas.lego.com/product-ideas/3b2e5ca7-13c5-4dbe-8c4d-cb9d22b40f93 ❤️ Thanks, Mark

This is our Blacktron monorail layout, shown at STEAM 2025 and NSC 2026 in the UK. Now 3x5 plates, 2'6" x 4'2". I used 6x 10355 Blacktron Renegade sets for the livery, with Technic panels for the larger structures. The sharp curves work well with no stress, thanks to some 1x2 plates with rounded ends. Radii 24M and 34M. The train motor works well as the motive power. The PF LiPo battery lasts up to 1.5 hours in either a single motor or double motor train. 3 batteries per train is sustainable for the show. I now have hills working too, similar to the original geometry of 6990. Mark

The newer switches are a bit stiffer than the oldest ones with studs. The longer cylinders help to provide more leverage for pneumatic automation. A single cylinder can push up to 5 switches and the new type of switches with the nozzles on the bottom are easier to build as a compact bank. This robot uses 7 cylinders and 17 valves (some in banks of 3 or 4 as a back-pack) in a 14-step sequence to sign "JOY" in semaphore: I tailored the length of the levers to align the cylinder travel with the valve lever range. A #2 joint plus a hole with 2 axles plus a #1 joint is the right length. Mark

A proper 30-function JCB Backhoe would be lovely, a worthy development of 8862 and 8455. Since the LEGO Ideas parts limit is now 5000 pieces, I hope Technic could reach that with a functional non-car flagship set. Avoid Control+ nonsense and do it properly with pneumatics, including 3-function loader, 6-function backhoe, multiple compressors and servo steering. This should suffice, if I had another 500 hours to finish it: The loader and backhoe controls are laid out like the joysticks of the real JCB 3CX-Compact, so it would be possible for the user to drive them like the real thing. I took another 40 hours in 2023 to improve the servos for the steering as they need a good range of variable movement to do the proportions. Those need to be implemented in the next build. Drive works well enough from a single L-motor, with dual compressors from two right-angle motors taken from 51515, built as the "engine". I expect the 2-switch battery unit would be best for the compressors but a 2-port City hub could work with the train handset to do just the drive and steering remotely, leaving the digging functions as hands-on. TLG has not yet exploited the train handset's capability to rotate the dials, where it would be easy to set them up for drive and steering of an RC vehicle. And, best of all, the LEGO company must now have a deal with JCB, since one of the pull-back vehicles in January's range has their name on it. Mark

I'd love to see the SPIKE Essentials 2-port hub used in Technic, provided that the firmware was updated to use the train remote handset. This could control a car without needing a phone. It would be the equivalent of the City hub but with the Technic attachment method and a LiPo battery. The 3x3x5 motors would be useful too; those are the smallest but not in high-street sets yet. If there is to be a tower crane, based on the jib modules of 42146, then let it be one that builds itself by rising and inserting modules into its main tower. That would be a decent flagship. A LEGO mobile crane has the difficulty that having more than 3 telescopic parts to the jib makes it too wide for the scale and too heavy to lift with LEGO actuators. There is a real crane that extends the idea of 42146 with a very long diagonal telescopic jib and twin cables to support the extension that is made from frame modules. Lichfield Station Crane December 2023 Mark

I agree on "worst". Having had the same problem with the 42131 front blade calibration and having reinstalled the app, I had more success when I repeated the individual function tests until each one rotated its function in both directions during the respective test, ignoring the times when they moved incorrectly. It seemed to be random but maybe it records the movements that were made during each test and takes those forward to the calibration stage. You could remove the ladder and wind the gears manually through the clutch to give it an offset. Then do it every so often when it falls out of calibration. Have owners of 42146 crane found that to be any better? I imagine a command to wind in fully would be subjective, based on how the strings wind on each spool. Or are all its 6 functions variable, without specific distance calibration? If that were so, it might lead to avoidance of Control+ sets with linear actuators but greater ease for sets without that combination. Mark

Given the "Earth Green" leaf pieces from 10289 Bird of Paradise, and the fact that is is retiring, it would be nice to see an E-type Jag in British Racing Green to keep up Technic panels and other pieces in that colour. A manual gearbox would be a nice change but I expect the Yamaha pieces would be employed in the next supercar as justification for their existence; 4 new complex pieces is quite an outlay. Mark

The motors are identical and independent. The differential is only a drive to the engine. The drive motors have to turn in opposite directions to go forward or backwards; this can only be done by a command of that sort from the hub. At step 198 I found that the tests were inconsistent in what they did to drive the motors. Test 1 drove the gear both ways sometimes and only one way at other times. Test 4 drove that drive motor in the reverse direction to what was prescribed, yet it would not fit into the model in a flipped orientation. I tested the drive motors with a battery unit and both are correctly wired, so it's either a bad hub or bad software. I'm persevering with the build in the hope that it was bad test software and that, when it calibrates (needing the model to be finished in order to hit all the end stops at the right times) it will work OK. This all puts more nails in the coffin of confidence in PU hubs and software. Mark