Brickthus

Instead of the white fan blades, try Unimog door panels. These are available in both hands, to make mirrored rotors. Definitely the broad blades. The thinner ones don't work very well, as I tried a 12-bladed fan with those. I have run a counter-rotating twin-rotor (not intermeshing) experiment with 1 5292 motor per rotor and 4 door panel blades on each one. It achieved 200g of lift on a 270g model at 9.1 Volts (equivalent to fresh batteries) and took about 2.5 Amps. The motors won't last long at that power level. I am using a bench power supply because batteries run out too quickly, but I would move to the light LiPo battery once I have a datum point for the motors and frame leaving the scale pan! The 5292 motor is definitely the right one - fast and powerful. An XL motor is just too slow, and a pair of M-motors geared up 5:1 doesn't do as well as a single 5292. A pair of L-motors geared up 5:1 is a possibility. I did try this with 6 9396 blades angled at 22.5 degrees on a single rotor but those blades are not designed for creating actual lift and the model didn't make much of a down-draught. Another key is to widen the radius. I kept extending the radii of my Unimog door panel rotors. A key with this is to make sure they can't fly off, so I use 8M axles with bezel end and also 16M axles with multiple half bushes to keep them attached. If a single half bush flies off then you just have time to shut down before a blade follows it! I use a piece of Lexan sheet to avoid injury! For maximum thrust, wide radius and high speed are needed. Maximise swept area per second. Also get a good blade angle so that the air flows over both surfaces. It's not just a paddle! Too steep an angle and it will be like a stalled wing and create turbulence rather than thrust. Best wishes for take-off! Mark

If there is a standard expansion pack then that would interest me. I had not ventured much beyond the standard kit with NXT 1 or 2 and did not mix my NXT kits with the rest of my collection. I would certainly like to try out the elephant. Whilst I have enough NXT2s and sets of sensors for them, it would not make an NXT3 purchase "urgent" for me, but the expansion pack might be hard to resist! We will have to see whether the retail kit is as expandable as the education kit, since the expansion pack is designed for that. Looking through the expansion pack parts table I probably have most of those parts already! A building expansion pack is something that was lacking for NXT2: There was a good range of extra sensors to try but you had to be a dedicated NXT fan to build much further in the same studless style beyond the standard kit. Another hurdle was that it was more difficult to get the special light grey beams for colour matching. Otherwise it was more difficult to integrate the NXT with standard LEGO bricks and plates. My best endeavour to integrate NXT into the brick and plate environment was to mount the RFID sensor behind a 1x4x3 panel, using the old z14 bevel gears as spacers to place the sensor as close as possible to the back of the panel in order to hide it in a wall, so that it could recognise the tags on passing trains. The NXT could then sound the right bell code in the signal box and could send a PF IR speed signal to the train with the IR Link sensor. PF control has been my main interest in the NXT so far, so each of my NXTs will have an IR Link sensor and IR receiver so that they become intelligent PF devices. I have also done machine to machine IR interaction with just PF on its own, but obviously the NXT allows more variation and intelligence in the interpretation of the signals received. Since the NXT3 IR sensor has two sides (presumably Tx and Rx) and comes with the retail kit, I assume the hardware will be capable of performing the functions of the HiTechnic IR receiver and IR Link sensor. My guess is that an NXT3 could control many NXT 1 or 2 units via the PF protocol even if no other daisy-chaining is specified as standard in the backward compatibility. It will just be a matter of sending the right codes from the NXT 3 IR sensor and having different programs to interpret them in each NXT 2 unit. Whether the codes are similar to PF codes, the same with a different header or completely different remains to be seen. The IR beaon has shorter range than a PF remote, probably because it uses just 2 AAA batteries, not 3. I hope we will soon have NXC programmability for the NXT3, given its different processor. That is a key to backward compatibility. It looks like the sensor ports will have the same electronic protocol and would be able to use NXT2 sensors, but that most NXT3 sensors will be digital (perhaps even the touch sensor as the data sheet says it can count pulses, perhaps taking on that role to unburden the NXT brick). The motor ports might be more different; The NXT2 ones frove the motor with 2 pins and I think this will be the same except for a beefier motor driver (like the one in the PF V2 IR Receiver), but I think the other 4 pins might fulfil the digital sensor function rather than the simpler quadrature sensor of the NXT2 motors. After all, the literature does say the NXT3 will recognise motors and sensors as you plug them in, which requires digital communication unless standard resistor values are used (they were used as switch recognition on the Cybermaster, to recognise different tools for the tracked robot; the white, yellow and red switches contained different resistors). The use of two types of motor is good. The smaller one like a PF medium motor with encoder, fitting more easily in place of an M-motor in Technic models, which makes for easier upgrading of Technic model intelligence. I think the large one is mainly a digital upgrade from the NXT2 motor; the casing appears larger at the motor end, perhaps to accommodate the digital circuit in place of the NXT2's simple quadrature encoder. Mark

When I have gathered the parts, it takes about 20 minutes to make 9 32M straights or 4 curves (half a circle). Since the parts are mostly 2xn plates, I have ice cream boxes and freezer bags with most sizes of them handy for my railway. I soon ran out of blue parts after making the four blue curves but I had the black parts in quantity! I made some text instructions for the basic track pieces. Mark

Another update to the monorail pictures, now with a heart-shaped circuit. Developments: - I added a bit to the curves, so they are now 38M long when straightened, for a more accurate 48M radius to the track centre. - The crossing has been updated so it works better. Train progress is not impeded at all, even if it occasionally jumps over a returning folding track section at particular speed settings. - I've now implemented the start/stop system of the original monorail by adding a sliding piece to a standard straight rail so that it pushes a slider on the train and changes the polarity of a PF pole reverser switch. The IR remote control is still available as well. - The layout now has tracks on top of each other - a concept that needed to be proved for any large layout ideas to work. Some of the curves have few-plate rises too, to check that spirals can be done - 4 plates per curve would be needed for a full helix to work. It is now possible to go for the world record of 362.5m with this system, as long as you get at least 40000 1x2 plates, 22000 2x2 tiles and 2x2 plates and 8000 2x8 plates! Now that I have many different track piece concepts working well, I might have a go at points and crossovers, something Masao Hidaka has shown on LEGO CUUSOO, as well as improving my train! With points and crossovers there is some point to having more than one train! Mark

The new LEGO PF Servo Motor will be out as a single-item set in March this year. That means this simple solution will be available without buying too many 9398 Crawler sets: Just a 9V supply and a 1-way switched supply is enough to drive the LEGO PF Servo Motor as it returns to the centre position when C1/C2 power is removed. I drive the servo with a standard PF battery box and pole reverser switch (one way and centre only, the other way disabled with plates blocking the lever). I tested it successfully with several lead added so I know it will work 2 metres from the control panel. The PF pole reverser switches make a control panel quite easily and the extra little switch allows the user to set the polarity for pairs of facing points (which is why I petitioned for it to be added). In the picture the mast foot clamps the point slider casing to the motor mechanism, keeping the end of the rack in the lever shoe under high torque. The lever raises the red piece when the point is set curved. The mechanism is designed to minimise the profile close to the track, to accommodate large train overhangs that would knock a yellow lever out of place. This solution is designed for best reliability in places you can't see or reach over a 2-day show, such as a fiddle yard under the station (hence the stanchion). The NXT would not provide more than C1/C2 with the standard NXT-to-PF converter lead but the PF lead could be hacked to add a 9V supply for several servo motors if necessary, or a bridge rectifier could be added to each lead if single motor sub-system autonomy was required. I dare say an easier PF Servo Drive solution for the NXT may present itself in the future. I can see NXTs driving PF Servos being popular for robotics. For the moment the easiest no-mod NXT solution is to use a PF IR Receiver and for the NXT to drive it (or several of them) with an IR Link sensor (which are on January sale at LS@H). More mechanism pics in this folder. This is simpler than my previous solution, which used either PF, monkey or 71427/43362 gearmotors but more gears: This previous solution fell foul of a sticking switch point. It stuck just a bit more than the torque of the white clutch gear. The clutch gear would eventually wear out, which is why I went for the servo motor solution instead - more torque, no wear-out mechanism and open-loop deterministic position - it ticks all the boxes! Mark

I once fixed a OO model of Big Bertha that went in the wrong direction for the current - no good for a banking engine! One side of the electrics were connected to the chassis so that couldn't be changed but, as any A-level physicist knows, turning the magnet round will also change the direction of the motor! I built one of the 2-6-0+0-6-2 LMS Garratt engines that used to haul 99-wagon coal trains from Toton (in the Midlands) to Brent (London). They were built to replace pairs of 3F and 4F 0-6-0s but the designer tried to use the same wheel bearings with a heavier loco and reliability was poor as a result. Most of them were also fitted with a rotating coal bunker, so I motorized this with a micro motor in the cab. I have 1 9V train motor at each end for traction and 1 gearmotor at each end for turning the driving wheels, which are suspended off the rails. The wheels are too small as they should really be at least 5ft diameter, but TLG never made the 40mm thin pulleys I suggested! More pics in this folder. Mark

That would be my preference. The PF Train Motor 88002 is so much better than the RC Train Motor 8866. The 8866 one was geared too fast and had too little torque as a consequence. It might be OK for kids to run a light train too fast and fall off at the corners, but that doesn't meet the AFOL market. I did comparative torque testing of 10153, 8866 and 88002 and it confirmed that 88002 is a bit better than the old 9V motor 10153. I did get a few 8866 motors anyway, for testing and for a prospective multiple unit train, which would use at least two motors, run faster and with a much lighter load than a typical goods train. I wouldn't use them on a goods train. The building versatility of PF is its advantage over RC. PF also allows 8 trains to RC's 3. More than 8 trains can be controlled with PF if you know how, with NXT control! The V2 IR Receivers, upgraded for 9398 Crawler and now shipping as the default IR Receiver, boost the power available when running 2 PF Train Motors together, as serious AFOL goods locos do. The only limit then is the 800mA current trip from the PF LiPo battery. Of all the heritage railway systems, RC is the first to forget! Its other major flaw was the white nose piece on the passenger train, which was voted the "second most useless piece ever" after the dinosaur body. Not only was it a single-use piece of POOP but it didn't fit properly either! Mark

He has some G-gauge and some on standard LEGO track. Have you thought about 8mm scale LEGO trains? This is 8+ wide for UK, 10+ for US or EU prototypes, 1 stud to the foot scale. I've done this since 1996. So far I have 10 diesels, 7 steamers and a 4-car tilting Pendolino EMU. I just built a new diesel shunter with Power Functions for speeds of 0.5 to 20mph in 2 gears and onboard decoupling. You can run standard LEGO train motors and wheelsets or use Technic motors with Power Functions. Mark

I have built inclines for both standard 6-wide trains and 8+ wide 8mm scale trains. To build to scale, the maximum slope should be 1 in 30 for any model railway of any scale or gauge (true for N, OO, HO and O gauge too). That's 1 plate for every 12M or 4 plates per 48x48 baseplate for a modular layout. I do this on the straights and reduce to 1 in 40 (1 plate per track piece) for the curves, which have 2 straights between each standard curve. In Flexitrack I have mad a similar slope by supporting the track on a series of composite tiles that increase in height by 1 plate for every 16M of circumference at the track centre, supporting every 8M with a 0.5 plate rise (on the studs of jumper plates). The first and last rises are 0.5 plate per track piece. I have a height between lower and upper trackbeds of 48 plates with minimum headroom of 37 plates under a bridge i.e. about 41 plates difference in trackbeds by the time the upper track is supported. For ordinary 6-wide trains I followed the 7777 ideas book, with a maximum slope of about 3 plates per piece and a maximum rate of change of slope of 1 plate per piece i.e. 1, 3, 6, 9, 12, 14, 15 is acceptable for standard train sets. Mark

I've updated the pictures of the new monorail. I now have straights, curves, 2 types of hills (48M x 5 bricks high and 80M x 10 bricks high) and a flat crossing working well. I have built at least enough track to replicate the 6399 Airport Shuttle monorail set. Mark

It is probably Joe Meno. Not sure but it might be one of these layouts you saw (top 6 of those shown on the link). I have only done this system since the beginning of December 2012! Masao Hidaka began it about a year ago - see the LEGO Cuusoo link above. My idea is to get the engineering to work, at least for a standard set of parts that replicate the functions of the the original. That will allow it to become popular and then we will see people doing more imaginative things with it. Already more is possible - different hills, multiple heights not just 10 brick intervals, a flat crossing, a double crossover... One of the best things is that long straights are not rare like the original! Mark

Thanks guys I put up some information in a text file to explain a bit more about the concept and how the functional parts of the original may be recreated and extended. I am writing some word-based instructions with parts lists for the track pieces I've made so far. A step forward with the switch-on-the-train concept, from the original start/stop rail and motor switch, is that a new way of mounting the switch shows similar force required to change it as the original needed. This bodes well for the train staying on the track and being able to change the direction switch at a similar speed to the original. Whether it will do it well at low speeds I will have to wait and see. I thought this was a good function to recreate because then I will have all the functions in the 6399 Airport Shuttle set. I also understand why the train sometimes sticks on the crossing so I will apply some measures and evaluate the improvement. Mark

Please see this topic This is a new sustainable monorail system using basic parts for infinite tracks and Power Functions for power and control. I already have most of the parts to emulate the tracks of the Airport Shuttle - only the start/stop rail function needs more development. Power Functions means the train handset can control it anyway. Mark

Please see this topic This is a new sustainable monorail system using basic parts for infinite tracks and Power Functions for power and control. Mark

I have been developing the new Monorail system suggested by Masao Hidaka on LEGO Cuusoo Folder when moderated My layout has straights, curves and slopes well proven. The sizes are 1.5x the original - 48M curve radius and 6-wide (or wider) trains. I also tried a figure-eight with the crossing. So far I have a 5-car train with 2 motors, LiPo battery and IR Receiver. Top speed is a bit more than the original but it is also variable with the train remote. I am working on a flat crossing, which TLG patented for the original monorail but never released. Shown here is the rail-flattening version but I also have a turning rail version. I am also working on the motor switch function using a PF pole reverser on the train. I have yet to do points but Hidaka has started on these, as well as a crossover. All tracks are made from sustainable basic parts. TLG can't take away our monorail again - as long as there are basic parts there will be monorail! There is also more variation possible. I have an 80M/10-brick slope and two 48M/5-brick slopes. Both use the same angle modules at the ends, calculated not to strain parts and each joint fixed with two clip/bar hinges for robustness. I got into 0.1M offsets to make the angles! The black and yellow colour scheme fits with Blacktron quite well but you can vary the colours to suit your chosen theme. TLG will never make the original monorail again, no matter how much we might wish for it, because it is not commercially viable. I believe this system presents a sustainable future for LEGO Monorail. That's why I decided to help develop it. Please try it yourself and support it on LEGO Cuusoo Mark

I designed a circuit that switches between two light bricks, using the standard PF protocol. It sets the lights to the direction of the train and, if you have a battery on the train, it keeps them on in the previous direction until the train drives the other way. It assumes ou are using 1 light brick for white and another for red. This loco has the circuit installed. It has one red and one white light at each end. Fortunately it is short enough that a light brick can reach to do the white light at one end and the red light at the other end. I expect some locos would use up to 6 light bricks to do all the lights but the circuit has the capacity to handle it. Mark

In that case you can improvise on the curves with a plate and tile as SNOT for 0.8M, or use 1x1 clip plates with the innermost one having its two clip pincers arranged orthogonally to the track. There are many ways to get <1M! If the 1x8 sleepers will not have the pins then their clutch onto baseplate plates will be weaker. This is not good for ballasting because a ballast scheme relies upon parts being fixed to the 'sleepers' to make a track module that then fits into the baseplate module. Mark

I used the book "The Diesel Shunter" by Colin J Marsden for the shape, size and features. I googled "Class 08 Cotswold Rail" to get livery pictures online. There is actually one in the latest issue of Rail magazine. I have had parts doodled for this loco for about 9 years - the front grilles, some plates with the black and yellow tiles on and a SNOT-lettered "CR" logo, which proved too small for the model. I had tried previous chassises including a 9V train motor with 2x 71427 gearmotors on top, with individual cog drives to each of the 6 wheels using 14:20 bevels in a thin space! Much better with the Emerald Night wheels though. In the meantime, Cotswold Rail went bust 3 years ago! There are still two Class 08 diesel shunters with this livery, 08871 with yellow rods and 08847 with red rods. Mark

Then there is a choice: a) standard plastic tracks as TLG wants to sell them, which is to make sure they sell all the types they make by mixing the ones we like with the ones we don't like, and b) build your own like other model railways with Ben's new tracks, compatible with 9V or PF. It's quite a stark choice. Experienced AFOLs are ready for Ben's track solution. I petitioned him for sleepers to fit with standard metal rails that could be cut to length because it is one way to solve both the 9V availability and wider-curve problems. I suggested a 1x8 plate or tile with clips in positions 2 and 7. He found a solution that is more LEGO-esque by using the clutch of a plate to hold the rails in place, and is also easier to assemble than threading sleepers onto pairs of rails. For the experienced AFOL there is a case for having both systems - Ben's solution for a carefully-planned layout where track positions are designed before building and standard track for experiments and knock-up layouts. Many experienced AFOLs have a lot of track already; I bought enough for my layout plan at one time knowing that track was a high obsolescence risk. TLG then brought out PF and flexi-track so I experimented to find a way to make that acceptable for use in a large layout by ballasting, canting and sloping it. Having done this I see that Ben's solution is good for the longer term because Code 250 rails are used by other scales and gauges so there is support for the rails in the wider model railway community. This makes the metal rails less obsolescent. The key to supply is Ben's sleepers; if his wheels are anything to go by then there should be no problems with long-term supply. Therefore the conundrum remains: how do AFOLs get the mix of track pieces they need for knock-up layouts, assuming they don't have a lot already, whether or not their best layouts will use Ben's track. I suggest that Ben's track will reduce the AFOL market for standard tracks. This will not persuade TLG to make track packs that we might like so we will continue with cheap curves and flexi-track and expensive straights on Bricklink. As long as they make straights at all, they will have to put enough of them in packs with other parts to make the straights sell at a similar rate, so we just have to keep petitioning for more straights; the other parts will sell anyway because they're in the packs and they fulfil the child market for make-a-circuit layouts. Flexi-track parts now become more useful to us because we can use them to try out alignments before settling on a custom curve design using Ben's sleepers. They are also useful for roller-coaster slope changes. Given the investment required it is always worth trying out an alignment before buying a lot. Standard curves will just have to be used for end-of-layout spirals to go up and down to a fiddle yard or for large turntables (88ft diameter)! Another use is for making a jet engine or other large round model. We LEGO builders have always been good at finding new uses for parts! Mark

I build regularly to 8mm:1ft scale, 1:38.1. This fits with the track gauge of 37.66mm being the standard gauge of 1435.1mm. At this scale British stock is 8+ wide - I start 8-wide and add the trimings or improve the body width from there if it's 9ft or more. At 8mm:1ft scale a minifig should have 1 plate added to its feet for 5'4" and 2 plates for 5'11, the average female and male heights. Adding a neck-held item like a rucksack helps to add height to the minifigs but they are meant to represent children anyway so being shorter than average adult heights is OK if you don't want the extra plates. For 3'6" gauge the scale to L-gauge track is 1:28.33 or 10.76mm:1ft. This might mean minifigs could have longer legs, like Woody from the Toy Story train set. The minifigs would be slimmer, less than 2ft wide and therefore more like real people! I see the coupled wheels of the loco are 36" so, at 10.76mm:1ft, 32.28mm is the ideal LEGO scale size and large BBB wheels or Emerald Night (red-belted) wheels are closest at 30.4mm. The red belted wheels give plenty of grip if they are the motorized wheels. I tend to think of each BBB wheel size as covering a range of 9" so for 8mm scale I use large ones for 3'9" to 4'6". For 10.76mm:1ft scale it is 2'10" to 3'5" for the large wheels. It often pays to have wheels a bit smaller than proper scale size because the flanges on LEGO wheels are bigger than on real ones and extra clearance is a good thing, especially on a bogie. That's why I use them to represent wheels of the exact scale size and a bit larger. A coupled wheelbase of 6'9" becomes 72.63mm or 9M, so 4.5M and 4.5M axle centres or you could extend to 5M and 5M for convenience and ease of connecting rod construction. With a total wheelbase of 21'10" (234.9mm = 29M or make it 30M if you use 5M + 5M for driving wheel centres) I would recommend the 6 drivers on one bogie and the 4 trailing wheels on another. This means you would need a driving axle down through the bogie centre if there is a PF motor in the loco body instead of using a train motor in the rear bogie. What is the width of the loco? Just multiply by 10.76mm:1ft and round up or down to the nearest 2M. It is possible to build to the nearest 0.2ft using SNOT tiles (on their side), or to the nearest 0.1ft if you have space to fit SNOT and half-stud jumpers inside. My latest PF shunting loco incorporates the battery box, IR receiver, 2 motors and a gearbox on the red-belted wheels, so this shows the minimum size to fit all the parts in. The loco is more Technic than brick-and-plate but larger locos have more freedom to be brick-and-plate with some Technic inside; not such a squash for the PF parts! I have a few steam locos too. Definitely consider the power and speed you need before fixing the architecture because this sets the motor type and gear ratios. Do you want to reach the loco's top speed of 53mph? Mark

Most interesting. This seems to be the LEGO-compatible answer to the O-gauge and larger gauge track construction, where anything goes regarding geometry. Code 250 rails are used in O-gauge and larger gauges than L-gauge so it is the logical choice. The tile-top parts support a lower level of ballast than the current ways of ballasting sectional track or flexi-track. No need to cover the plastic parts of the track pieces with tiles for artificial sleepers. That said I would like to see the sleepers in DBG (steel) and LBG (concrete) to add to the reddish brown (wood). I would like to see radii of 88M and 104M. Not sure if alternating 56M and straight ones would squeeze smaller than 112M. I might have to swap each 4th 56M one with a 40M one to get 104M. Ballast might be tricky, or else bespoke. 1-plate gaps are guaranteed for all sleepers, with extra gaps filled with clip plates, cheeses and the like. A lot more unique combinations of small LEGO parts to fit the geometry. More trickly for tram tracks where a tight fit of the street round the track is desired. Unique ballast part comvinations are fine but it means less mass-production for a layout i.e. difficult to repeat the pattern for a point because beyond standard track pieces no two would be alike, so it would take longer to do them all. Just like a model railway of another scale! The bespoke geometry moves the trade towards sprinkled ballast for LEGO non-purists. I wonder if we could get LEGO granules in bulk - that would keep it pure except for the glue! I look forward to seeing what sort of station throat arrangements will be possible once custom rail lengths and half-sleepers are applied - any geometry built in O-gauge will be possible! Narrow gauge too - just cut the sleepers in half and butt the outer ends together to get 4-wide track! Mark

Contents of this re-post were kindly resurrected from the 5 days of lost topics by Boneparte. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- This is my MOC of the ubiquitous British Class 08 diesel shunter in 8mm:1ft scale. It has been eagerly awaited by those involved in the PF L-Motor discussion. I'm now at the stage where the functionality and basic body are there but I still have the trimmings to do - railings, ladders, fuel gauge, buffer beam and grille improvements, as well as cutting down the rods and their pins. On a Hornby layout these engines melt into the background so I wanted to make this a bit special. My plan was to create the model with 3 essential functions: - Maximum speed around the design speed of 20mph. - Minimum steady speed of 0.5mph for shunting at prototypical speeds. - Decoupling to remove "Hand of God" operation. The model contains a gearbox, actuated by a PF M-motor, which selects between high ratio, low ratio and decoupling. The drive motor is a PF L-motor and the wheels are from an Emerald Night set. Lots of traction with the red belts! I have put functionality before aesthetics as usual. The loco is in Cotswold Rail livery, of which no. 08871 is an example. i understand the company owns 6 of this class of loco. I took the easy route so far, just quantising the livery into brick widths and plate heights. As long as it's recognisable it'll do because I'm not trying to represent them. The grey with bright lettering will make a change from the green or blue of many other British locos. In order to create the functions, the two motors, gearbox and IR receiver have to fit inside. This means the model is slightly long for the scale but at least it fits into the required height and width. The length is grille + 2M of IR receiver + 8M of battery box + 7M of motors + gearbox + cab end. The coupling system can cope with the extra length so there is no compromise on shunting ability. The wheels are a bit small for the scale but this is common to other vehicles at this scale using standard LEGO train wheels. The Emerald Night wheels were selected for red-belt traction in preference to the larger BBB wheels that do not have a belt groove. The loco has two of the distinguishing features, the first is the yellow radiator grilles on the front. I could add more striped tiles to the side battery boxes later: The second is the yellow striped cab end, for which I cut up a few 1x4 tiles, ensuring that I could use both halves of every one I cut: The cab end windows would be nearer the sides on the real loco. This would be difficult to make, requiring a lengthways cut of 1x4 tiles and then a few 0.5x1 parts for the other side. This was a cut too far, but might be a sticker job for someone else. The IR receiver is nicely hidden at the front, behind the radiator grilles that open just like those of the real loco. This allows for changing channel. The grilles will pass IR light easily enough and I used clear plates behind them to also pass the light through to the receiver. It still needs care because the controller has to be able to see the front to operate it! I tested the loco through the fiddle yard of my large looped-eight layout. I think insufficient speed is a greater challenge than lack of IR controllability. I made an IR repeater circuit for use in tunnels. One criterion for exhibition is that the public should always be able to see a train moving at a show. Spending too long hidden in a fiddle yard will not do! Therefore I'm happy with this loco stayng on top in the yard, leaving other locos to do trip workings. I will take and post more internal pics in due course because I'm sure you'd like to see the gearbox! For now here's an underneath pic: You can see the coupling mechanisms using 2x8 plates with holes. These connect to the 9M racks that are supported by 5M black studless beams. From each rack there is an axle with a z16 cog on the rack and a z8 cog driven by a worm. The 2 worms are on an extended shaft driven by the gearbox and each has the same amount of play in its axial location. This allows lateral movement of the coupling over a limited range to cope with changes in the track curvature. The range is moved by the decoupling mechanism. In the picture the decoupling drive would send one coupling up and the other down or vice versa. The direction may be selected because the decoupling operation might take place on a curve in either direction. The z24 cogs keep the wheels in sync and the rods are more for show. I have a prototype where the rods did the work successfully. The drive omes from the gearbox onto the middle cog. This is in preparation for a test to see whether another chassis could be articulated whilst keeping the wheels in synce with the chain of cogs. This would have variable legth rods, a technique I used on by Class 14 loco. The idea of the articulation is that the chassis at the moment is the longest that can get round standard curves. It is also OK on flexitrack but needs to take care on points, especially with the moveable blade and the check rails. It would be nice to improve reliability of operation over points, especially for a shunting loco! The light bley parts with 2 pins each are the main Technic to stud connectors. Studded beams with holes are used in the cab and these hold the cab end body to the Technic parts of the gearbox. At the left hand end you can see some of the cogs in the cab, either side of the coupling 2x8 plate. I used 2x4 tiles and some hinge bases to hide varous cogs because they extend to more than 6-wide inside. One window is a composite for the same reason. The gearbox width is the reason the bodyside grilles by the cab windows currently stick out too far. I plan to revise that bit. On the roof the IR receiver plug is clearly visible on top of the PF LiPo battery box. I was pleased to be able to minimise studs on the roof on this occasion - a number of my trains might benefit from a refresh in this aspect, now that we have a good range of cheeses and curved parts. There is a 2x2 tile that sits proud, covering the on/off switch. Originally it was just the tile and a 1x1 round plate underneath but I added a minifig flipper to help the tile to stay in its slot. I might change this if another part is more suitable but it needs to have a small bit to actuate the button and a stud on top to attach the tile. I am particularly pleased with the crawling ability of this loco. It has been able to push a heavy loco with two depowered 9V train motors, enabling it to shunt locos as well as rolling stock. LEGO trains have had issues with crawling ability, either being unable to get enough torque at low speed or overheating 9V train motors in the process. Therefore this gearbox technique applies particularly to fans across the pond where trains go so slowly! I would put a gearbox in a larger loco so as to have a crawler gear and a high-speed gear. The gear ratio between low and high speed is currently 9:1 for 0.5mph minimum and 20mph maximum and is a squeeze in this loco, not so bad for a large loco. However, some motor torque is robbed by having the geartrain connected because in high ratio the motor has to turn the low ratio shaft 9x as fast! A higher ratio would suffer more in this respect, whatever the loco size, so a high speed of 60-70mph for a large loco (3x as high) would be a challenge. I have some ideas about this though. This is a true Power Functions loco - crammed in with a skin of bricks! I am considering whether adding lights is possible - there is a small space in the cab that might fit their 2x2 bricks! This folder has more whole-model pics and I will post some internal photos soon, but please let me know what you think so far. ------------------------------------------------------------------------------------------------------------------------------------------------------- Since the original post I am investigating whether it is possible to make the lower chassis flexible, allowing the front and rear wheels to steer. This will improve performance on curves and especially points. If it works I'll use flanged centre wheels and replace the rods with flexible ones more like those on my Class 14 loco (colour TBD). I deliberately made the drive from the gearbox go to the centre axle with this in mind so I hope the upper body doesn't have to change too much. The key at the moment is making the chassis pivot points rigid so that there is negligible vertical movement - just enough to work with a change of track slope. Mark

Here are my diesel locos, UK Classes 08, 14, 20, 28, 35, 37, 44, 47, 50 and 66. If you can get a copy of British Main Line Diesel Locomotives that has all the 4mm scale drawings, specs and pictures. There is a version for electric locos too. Mark

Unfortunately the 5 days of posts lost in the server transfer included the write-up of my new shunting loco that is packed with Power Functions There are pictures of the zig-zag end, hidden IR Receiver and underside (decoupling) in the link. I'll just have to write it up further when I take the loco-dismantled photos soon. Mark

Thanks for all your hard work. It's a real shame about the 5 days lost. The lost data includes the write-up of my new shunting loco that is packed with Power Functions, including zig-zag end, hidden IR Receiver, the new L-motor and a gearbox for 2 speed ranges and decoupling. Had I known in advance that a server transfer was due, I might have taken my own copy of what I wrote, so as to be able to paste it in again. Redundant systems are standard practice for safety engineers! Ah well, I'll just have to write it up further when I take the loco-dismantled photos soon. Mark