Brickthus

I saved a few links from a while ago. We did manage to get hold of some tubing suitable for pneumatics, in grey, black and other colours. It was a bit smaller than standard LEGO pneumatic tubing, which is also smaller than the tubes used in old Town and Space sets. We put a big order together as a group, for pieces 25m long. I have used about 1 piece of grey and 1 of black for pneumatics so far, cutting to length with a Stanley knife on a sacrificial chopping board. Most companies would be happy to supply a sample of tube so that you can confirm which product to buy. What you would need for pneumatics (or to fit onto 3.2mm rod-based pieces) is 4mm OD, 1.6mm ID Link 1 Link 2 in German, which might be the company we used. Pic 1 shows the tubing. Most is grey with one of the sample pieces in blue. Pic 2 shows that it works well with pneumatic parts, including 3.2mm rigid tubing. Other than that, a google search for silicone tubing 4mm OD 1.6mm ID should help. The old set tubes might have been 2mm ID and made of PVC, not as good for pneumatics as the silicone tubes but able to go onto the old 1x2 plate with fatter twin-prongs that was on the front of the Classic Space ships. Happy hunting! Mark

Good for TLG, releasing a set with a tram designed for this conversion. And well done Nacho. Interesting that this set should cost more than the RRP of the original monorail sets! Perhaps the centre of gravity is too high for conversion to a faster monorail, but one with standing passengers shouldn't go too fast! Mark

Most people use either Brickshelf (dedicated to LEGO, folder structure available, but not always reliable) or Flickr to store their photos online. Then it is a simple matter to copy the text from the address bar to create links in your posts. Best to upload in Web large format 640x480. I usually add watermarks so people don't copy so easily. Mark

I would like to see if there is any difference in the nozzles between the new and old cylinders and valves. With the existing cylinders it was possible to bore out the nozzles a bit, to reduce airflow limitations if fast response is needed. Care had to be taken not to damage the top seal in the process. If the new cylinders had tighter nozzle bore then it might simulate hydraulics better but only with a slow flow rate i.e. not so useful for fast movement or many compressor cylinders. From the box pictures posted so far it was not clear whether the nozzles were a different shape and would be unmodifiable, e.g. conical and hence becoming shorter if bored out and therefore unable to hold a hose. Mark

Great application of the theme to a similar train, and well catered for passengers and cargo. Some people have used the suspension piece from the Blacktron 6-wheeled vehicle as part of a close-coupling mechanism for extra monorail carriages. I found extra carriages can be pulled OK but pushing is harder for the motor, so bidirectional working is lost. The new monorail can have more carriages if there is a motor at each end. Really good M-Tron diorama. Monorail is very far from dead. There is a limited supply of the obsolete 1990s system but there is a whole new system to try that will never go obsolete! This was started by Masao Hidaka a few years ago; I decided to develop the engineering for the last 2 years. The new system uses only basic parts for track. Mostly 2x2 plate, 1x2 plate and 2x2 tile for curves. Longer 2x plates and tiles for straights. Pieces connected with Technic pins. I have recreated all the functions of the 1990s system track parts with the new system, and pushed out the limits: Straights were 8M, 16M, 32M, now up to 64M Curves were 1 radius, now 4 radii tested and more possible! Points used to stick, now more reliable, easy to fix and a single junction of up to 8 points possible with a single Servo motor! Hills were 10M high, now tested 5M, 10M and higher hills possible. Start/Stop rail replicated with PF switch but easier with PF IR remote control. Right angle crossing now possible. Helical tracks facilitated. Double track helix tested. Track colour can be adapted to the Space faction. Trains longer and faster - up to 0.95m/s (about 5x speed). Train travels up to 3 kilometres on a single charge of the PF LiPo battery. Train pic shows prototype Classic Space and Blacktron trains. I would like to do other factions too. These prototypes show the motor in the middle, like the old system, but motors at both ends can be better. This is how to get started making curved track. Please have a go. I think this is the best alternative to the original system, to keep monorail very much alive! Mark

If only that question had a quick answer! For bogie diesels I use the 9V or PF Train Motors as much as possible, 1 per bogie. Can use 1 of each. Easy for Bo-Bo. Trailing pony trucks of pairs of wheels to make bogies of 6 or 8 for Co-Co or 1-Co-Co-1. 2x 9V train motors with a wire between to share load in the event of poor contact on the points has worked well. One reason why I haven't gone to PF on the main lines of my layout yet. For shunters I use 1x L-Motor or 1x XL motor depending on space. My 0-6-0 Class 08 shunter has 1x L for power and 1x M for changing gear. 2 motors, battery box, IR Receiver and gearbox fills the loco body. My Class 14 trip-working loco has 1x XL for power but it fills the cab. The SNOT work means there is barely room for a cable under the hood at either end. The cables connect to an adjacent brake van with the battery and 2x PF train motors to pull the train. The brake van uses diodes to drop the voltage to the train motors so that the gear ratio between the train motors and the XL motor is right at the right speed i.e. no derailments. For steam tank engines (Stepney in yellow ("improved engine green"), Thomas in blue, Duck in green) I have used 1x 9V train motor (can use PF train motor) and 1x gearmotor (can use M motor). The train motor moves it and the gearmotor turns the suspended driving wheels. Gear ratio is important for realism! Toby the tram uses just 1x 9V train motor - easier. For steam tender engines 4-4-0, 4-6-0, 2-10-0 I have used 2x 9V train motors under the tender (can use PF train motors) and 2x gearmotors (can use M or L) to turn the suspended loco driving wheels. The LMS Garratt uses a similar scheme to the tank engines. The Hogwarts Express works well as 9V but needs more current than a PF LiPo battery can provide. 1300mA rather than 800mA. The train needed 2 more train motors under the first carriage when I added a 4th carriage. Could use another IR Receiver on the same channel but comms fault has a risk of derailment. Need a slave motor driver to use 1 signal for many motors. The E-Motor has a lower gear ratio than the PF motors. It is not so powerful as a drive motor but is better for propeller applications if you have a propeller-driven train! Mark

Thought I'd have a play with this kind of mechanism. Its functions are useful for engines of all sizes. I see you have put the pivots of the connecting cog support structure as close to the mid-point between wheels as possible. The design of the z20 cog, with a raised central portion of teeth, means they don't slide on each other very well. I played with moving the pivots towards the near ends of the adjacent 2-axle modules, even beyond the axle that the connecting cog meshes with. This means there is more turning and less sliding of the connecting cog on the cog that is on the wheel axle. I was using axles along the length of each bogie with cross blocks for the wheels. It does make the whole mechanism taller - perhaps it can be hidden inside the boiler or be made to look like authentic steam engine parts. From what I have so far it would permit a 4-2-4 configuration of driving wheels; with an extra feature the central 2 axle is able to turn by the mean of the 4s, which means a 2-2-2 is possible as a potential improvement on a rigid 0-6-0 that I have in this engine. At the moment it is OK on curves but struggles on the points. There is a trade because the engine is already crammed with 2 motors, bbox, IR and gearbox! Will post a pic when I have made more progress. Mark

Yes, I was thinking about a movie. Hopefully better than my previous ones. I still have some more endurance testing to do first, just to make sure. The previous test of over 3km on one charge took over an hour to do, with no failures of track or train. I'm looking for a comparative figure for the realistic train; anything over 2km (50 minutes) would be good, and I'm hoping it will be over 30 minutes by a good margin. On the layout, where there are 4 concentric curves with supports equivalent to 1 per curved piece of railway track, the track is solid. On the helical tracks, with half as many supports, there is a bit of sagging between them but no failures in 3km (244 laps) of running. These could upgrade to be like the 4-curve corner. The straights are solid even up to 64M long. I haven't had a stuck train yet, except when going too fast on the right-angle crossing. On the 4-track junction the movement from one track to the next is really smooth, no more vibration than normal running on curves, even at full speed. Perhaps a bit more vibration when it is set straight, depending on alignment. With the junction there is an operational risk of running off the end of the siding if it is set wrong with the train at full speed! I used brick 1x2 with 2 holes, and 2 pegs to join the rails together, to improve long-term reliability. It gets rid of the potential track twist between pieces that can happen with a single-hole joining brick. The belt drives take up any vibration in the transmission so the motors have no problems. On the curves the passenger modules can rock from side to side. This is a function of their attachment by Technic pins to the bogies. If axles were used, or a 2x2 swivel area rather than 1x1, then this could be reduced. It has not caused any reliability problems though. The straight hills (not in the current layout) may need a bit more development. I made these more robust than Masao Hidaka's original design, but with that comes more depth where the slope changes. They still use clip plates at the moment, with limited grip, so I could improve that by using Technic pins. I found so far that the hills are more likely to break with handling than with train movements! Mark

This is how to get started making the curves. They need mostly plate 1x2, plate 2x2 and tile 2x2 on top. Each end has brick 1x2 with 1 or 2 holes, pegs to link to the next rail and 2 plates 1x1. The straights are even easier, mostly plate 2x8. All basic parts that will never go obsolete. This monorail is for keeps! You can also change the colour of the track to suit the theme - either town or a Space faction. --Ed 20180206: I have developed the train into a proper Classic Space monorail train. It has interchangeable cargo pods including tools, foldable scooter, power packs and medical stretcher. The train is geared down 5:3 so that it climbs well as a realistic train with a bit more weight. Still a lot faster than the original 1990s monorail. The battery removal is facilitated with removable roof sections as well as the sides bearing the Space planet logo. At the right end in this picture the lights flash as the train moves. Mark

My new monorail, which began with Masao Hidaka's idea on LEGO Ideas, now has faster trains and a larger layout. - The trains now use PF Train motors, 2 per train, with belt drives. This is a much simpler transmission than the previous trains that used gears. - The train bogies are of Technic construction. - Powered by PF LiPo battery with PF IR Receiver control, S-Brick compatible. - Flashing lights in proportion to speed. - Junction with PF Servo Motor and rack system. - Speed is now up to 0.95m/s averaged over 10 laps of the 12-metre circuit. Full details and discussion here (and scroll down) Mark

My new monorail, which began with Masao Hidaka's idea on LEGO Ideas, now has faster trains and a larger layout. - The trains now use PF Train motors, 2 per train. - Powered by PF LiPo battery with PF IR Receiver control. - Speed is now up to 0.95m/s averaged over 10 laps of the 12-metre circuit. Full details and discussion here (and scroll down) Mark

Here's an update on the new monorail system. It's been a while since I last posted here on this topic! Trains: I now have monorail trains that can move at up to 0.95m/s (average speed over 10 laps of the track circuit below) - A lot faster than the original and about 3x faster than the earlier trains with PF Medium motors. The fast trains use PF train motors with belt drives to the adjacent bogies. The Blacktron train features flashing lights, with flash speed varying with the speed of the train, up to almost-constant at high speed. The Blacktron train has an opening cargo pod. The Classic Space train has passenger modules based on Benny's SPACESHIP, with room for 2 minifigs in each one. Each train's battery is in the pod with the logo - SNOT construction for the Blacktron one. - Easy removal for charging is possible. Train performance of speed and battery life varied in my experiments; it was better with more wheels powered. The best result (fastest and furthest) was where I swapped the train modules around, to put both motor sets together with a battery in between. - The train went for just over 3 kilometres on a single LiPo charge, changing direction every 10 laps (so no direction-based cheating!). I have updated the trains a bit since these pics were taken. - The trains are now more robust and just as fast. - The trains are now faster with a longer train. - I added small driver's cabs to the ends of the train, mounted on the bogies and based on the scooters from Benny's SPACESHIP. Cabs allow the theme to go to the ends of the train whilst keeping the motors powering the wheels at the ends. - The Classic Space train is now motor unit - passenger module - battery - passenger module - motor unit, 2 middle wheels unpowered and 2 powered at each end. - With a partly-used LiPo battery the train achieved 14 seconds per lap, slowing to 18 seconds per lap over 40 laps, with no significant loosening of the new cabs. This is better performance than other train arrangements, fast, reliable and consistent. 2 train recommendations: - Each train that is expected to travel in both directions should have a motor module at each end of the train, with all unpowered wheels in the middle. - The number of unpowered wheels should not exceed the number of powered wheels. Track: I have recreated all the functional track parts equivalent to the original 1990s monorail, with some limits pushed out: - Straights, now up to 64M long, enough to enter and leave a helix. - Curves, with multiple radii, 4 concentric radii tested. - Hills, 15 and 30-plates high tested (30 plates = 1 stanchion from the original monorail), versatile to do any multiple of 15 plates or any height. - Points, after Masao Hidaka suggested a Y-point, I expanded that to a 4-track junction of 8 points with a single servo motor. That would be the entire station throat in model railway terms. Any smaller junction can be made similarly. - Crossing, a right-angle crossing with track that moves out of the way as the train crosses. May need the train to be at low speed but works well. - Start/Stop Rail and on-train switch, tested and performance about the same as the original, though Power Functions IR control supersedes the function. - Helical tracks, tested 2-track helix, works well for many circuits of the trains. The layout has expanded quite a bit since the picture at the top of this thread. Layout features: - Two twin track helices of 1.25 turns. I have some more parts to take them higher. - Tunnel made from Technic panels and #3 joints, can be done in the colour schemes of various Space factions. I have done Blacktron (pictured) as well as smaller Classic Space and M-Tron tunnel mouths. The idea is that a single ring of panels could be placed next to a crater-side cliff and the train could travel from one faction's base in one crater to another faction's base in the next crater, with different colours of tunnel mouths on each side. - The 4-track junction is to the right of the tunnel, with the Blacktron train. - The Classic Space train is at the far corner of the layout. - 4-track curve on the right. The right-most siding has the old train with PF M-motors. More pictures in the folder here Unfortunately Masao Hidaka's monorail idea on LEGO Ideas timed out, but it gathered 1688 supporters. If it is worth it then I would consider raising a new idea for a Classic Space Monorail. Please have a go at building some of this stuff. It's great for Train and Technic enthusiasts and makes really good use of Power Functions. Mark

I take it you are using a standard 9V controller? This provides smooth DC power, which is good, so lowering the voltage by 2 speed settings should help a lot. A bit more heat in the regulator is OK - it can cope with that. If you were using a 12V controller (as would be used for the 12V lamp posts) then I would recommend not using that to power 9V trains - the motors hate the half-wave-rectified power of the 12V controller and this would make them buzz and quickly heat them up. I have used a dual variable 30V 3-Amp bench power supply to control heavy 9V trains at exhibitions. I often run at no more than 7V, often as little as 5V. This power supply has smooth power and heatsinks for its transistors so it can supply lower voltage all day. Other than that, minimise the friction in your train wheels. The road-rail vehicle has tiny wheels that would cause more friction. The 12V wheels of the truck also have more friction than most 9V wheelsets (except the ones that were problematic a few years ago). Check with each wagon that the wheelsets rotate freely for a long time when spun with the wagon upside down. Also reduce the weight of any heavy wagons. Weight adds load to the motor, which reduces back-EMF, increases the current and the motor heats up in proportion to the square of the current. Mark

With very few exceptions, I don't bother with stickers. They are of little value to me. They don't perform as well over years as regular plastic parts, no matter how much TLG might like to make them of similar quality. When I buy a set, especially Technic, it should be OK as a model but it really needs good parts as I do more with it afterwards. For 42039 there are a lot of panels, as with many current Technic sets, and the panels are a significant proportion of the price so they have to be worthwhile. The black ones I can definitely use. I wasn't so sure about the lighter green initially but as long as another set uses the same colour in future years then that will be OK. Again the rectangular panels will be more useful than others. The white small panels and #17 and #18 I can use for aerodynamic models. The curved 3x11 are the same as those in 42025 (I have 4); I prefer the panels with fewer holes to the ones in 42009 ans 42029. I might struggle more to use the medium and long thin curved blades #3, #4, #5 and #6 - their aerodynamics are not so significant as #17 and #18. I'm fine with the new gear shift parts and the double-sided gears would be useful for selection from both sides at once - experiment TBD. The wheels are good, better than in some previous vehicles of similar type. I was pleasantly surprised with the finished model - it seemed better on completion than during the build. The wheel arch panels are of particular interest. Firstly, why on earth did TLG make them? They don't seem to make very good smooth wheel arches. A real Le Mans car would smoothe-out the bit between the wheels and the body for aerodynamic reasons. Secondly, I was interested to find out their circumferential coverage in making circles - 8 panels make a circle when connected with 2M parts. To keep the circle circular, I used this piece with a 12M axle inside the circle (all x8): It is quite possible to make a tunnel out of these rings. Light bley would be the best colour for that though. It would fit 2-3 trains or monorail trains with ease. Thirdly, if TLG made them in Trans-clear in future years (not trans-blue of any shade) then I would use them for a station canopy. If they were made in light bley or black then I would use them for Space. My guess is that light green will not use the whole life of the mould! In the light green colour, perhaps the best application is four of them making semicircles for an aircraft hangar in minifig scale - cue an airport! Functionally, 42039 has the usual 5 functions of a car plus the two opening ones and the front panel may be counted. This total is a bit down on the £10/function metric, though it is difficult to imagine what more a Le Mans car should have. Still, I got £10 off in a sale so no worries! Mark

You could try this robot. It has 4 functions and does 10 steps in a cycle. You could adapt the grab and chute to hold balls instead of long bricks. There is a pneumatic circuit diagram in the folder. Mark

I have a picture of the two units: The 138 unit on the left shows the IC I can't find any data for it online but it looks like it has these features: - Ground pin 1, positive supply pin 11. - Input pin 14. - Input balance/filter pins 2&13. Maybe set the difference between the short and long whistle pulses. - Intermediate balance pins 6, 7 & 12 (might be like a 748 op-amp balance function). - Output smoothing pins 3&10. - H-bridge drive command from pins 5&9 low side, 4&8 high side. On a previous occasion I thought the transistors likely to be BC series, so BC114 and BC115. The earlier unit used BC113. That means they may all be NPN types. Here's the other unit's diagram. Thanks for the sketch. No evidence of flywheel diodes from the circuit as you have deduced it. I may be able to draw it with CAD sometime. If the unit you have only works in forward/stop then maybe a transistor has failed. I wonder if a motor inductive discharge voltage spike caused the failure! Mark

If you would like to try a monorail that facilitates all the functions of the previous monorail system, plus: - Track made from basic pieces with no obsolescence. - Multiple curve radii (4 tested successfully). - Straights of up to 64M. - Crossovers and Complex junctions of up to 8 switch points driven from a single servo motor. - Right-angle crossing. - Hills of 5 or 10 bricks high, or as much as you like. - Helical tracks. - Colour scheme to suit any townscape or space faction. - Trains with full Power Functions speed control. - Trains at up to 0.95m/s (81mph scale speed for 8-wide train). Then here's a good place to start! Mark

My first project on the LEGO Ideas site is an Inductive Charging System for Power Functions LiPo batteries for Trains, Technic and Mindstorms. The project concept enables a train LiPo battery to be charged without manual intervention. The train stops over the charging coil. The charging coil would sit between the rails, powered from the standard charger. The receiving coil would be held between the bogies of a wagon, plugged into the charging port of the LiPo battery. The device would be compatible with use for Technic, Mindstorms and other themes, so that a robot could return to a charging station and charge itself. It might be possible for the charging and receiving coils to be two of the same device, minimising cost. This would bring LEGO products up to date with the charging of mobile phones and tablets. It may be a key technology to enable more development of Power Functions trains because it would make it easier to run them at shows. Please add your support to the project. We have 90 supporters so far, which is good for a technological project (as opposed to a populist project). Let's see if we can reach over 100 supporters, perhaps 150 in April! Even if the LEGO Ideas route is not the best route, your support adds weight to the case for pursuing another route, such as third party production or crowd funding. Thanks, Mark

Here is the circuit for the 9V train controller. To increase the voltage, reduce the value of R2. The voltage and speed settings will stay in proportion across a wider range. I recommend less than 10 Volts as the maximum output for LEGO motors, unless you intend to power a 12V motor. This would need R2 to be about 423 ohms, which would need a 3900 ohm resistor in parallel with R2 (currently 470 ohms). However, the best thing to do has already been mentioned - beef up the current to more than 300mA. The way to do this is to replace the LM317 in the TO-220 package with an LM337, which comes in a TO-3 package. You may also need a heatsink to dissipate the heat from more current at the standard voltage drop of 2 Volts across the regulator. It has been done successfully up to 5 Amps before. This may be in a very old post somewhere. I have used a dual 30V 3 Amp power supply on the main lines. This provides the smooth power that the 9V motors prefer. I am careful not to exceed 9 Volts. A railway show usually needs only 7-8 volts for an express train in a larger scale. Another way would be to drive the track power feed from a Power Functions LiPo battery box with a PF extension lead. The PF battery box produces PWM so there is more torque at low speed settings for a better pull-away from the station. It also gives up to 800mA so it will handle 2-3 motors with ease (assuming a 6-wide train). I exceeded 800mA with larger trains (4 train motors + 2 gearmotors + 3 lights, needing a total of 1300mA), causing the battery box to attempt to restart the train on the uphill section. You might find that the 9V motors don't like PWM (and buzz their disapproval) in which case a smoothing capacitor may help. Mark

Here's a good place to start. From basics to more advanced stuff, beyond the 8868 truck alternative model! Mark

Agreed. For most Technic sets the steering rake is not what it could be, so it makes less difference. It's mostly when we want to make proper models with a full steering rake that we notice the difference! Some of the best Technic set steering rakes are on F1 cars, which is ironic, given that in real life they have less rake than most road vehicles! 8479 bar code truck was the best example of steering rake with the 62mm wheels. That was long ago though. Mark

Carl's modelling expertise is such that he is limited by the LEGO medium. He regularly adds features that some of us would not have attempted! That lends itself more to a model railway for LEGO trains rather than a "LEGO railway". My own aim has been to prove that an entire model railway can be made out of LEGO. I modify only things beyond the electrical connectors. I have chosen to build to 1:38 scale - 1 stud to the foot. This makes rail vehicles quite large but I have had very few problems getting round curves. The large size has raised challenges of motorization - mostly overcome - and some of real momentum and inertia, but that is more fun! I have chosen a modular layout for ease of transport. I have spent some time creating ballast schemes showing the range of real colouring in track ballast. A mosaic of greys old and new, black, tan and brown can all be used, with occasional green where weedkilling hasn't been up to scratch! This has included track features - AWS magnets and TPWS grids for UK railways, point heater cubicles and transformers. I have blended mechanisms for point control into the scenery, some pneumatic, with servo motor control in the fiddle yard underneath. It is also possible to ballast, cant and slope flexitrack. Many proofs of concept demonstrate a set of technologies for use in a LEGO model railway. It just became such a big project to do a 16ft x 12ft one! For the trains I have put function before aesthetics. Many of my trains are 11 years old now, so quite a few need a layer of tiles on top! Have a look around in my Brickshelf trains section. Mark

I have done a similar thing with pneumatic controls. Pneumatics don't have to worry about hitting an end-stop or wearing out a clutch gear as a motor does. The pneumatic controls are attached to the underside of the trackbed panel and this sits on mostly tiles and a few locating studs to enable servicing. It works well with points and also the double crossover, which can be made to set both tracks straight at once. The layout modules have various heights and slopes for a double-track looped-eight layout - easy enough to fit the trackbed panel at any height. Module interconnections are flexible to allow enough hand space for attaching and detaching for transport. Controls are brought out to a convenient place in the operating well of the layout. You have the right idea with little to see on the surface. Mark

Thanks for the link Jeroen. Owen, some similar pictures are in my Brickshelf folders here and here Kevin and I both worked on pneumatic logic at the same time, using slightly different systems. My system had each logic gate cater for both hoses by default, like the OR/AND gate a few posts ago. Kevin's system usually passed on a single pressurised hose so that he could put many robot walker legs in series with the fewest valve switches; this uses 3 switches for one nozzle in an OR/AND gate and 1 for the other. I also used the single-pressurised-hose system in my Octopus Arm. I had initially drawn the OR/AND gate for that system in June 1999 (as a bitmap on my old Windows 95 computer!) but the Octopus Arm was the first of my projects that needed to use the system. My earlier pick-and-place robot (1996) suited the 2-hose system and incorporated a 2-hose exclusive-OR gate. We found that the technological concepts of LEGO Pneumatics developed faster with competition, much like patent races in other fields! This progressed as far as mid-stop pneumatics. Then I made the closed loop control servos so that a pneumatic cylinder can stop anywhere. It is great now to be able to help all of you to learn these systems, which begin where set 8868 took us in 1991 and go far beyond the scope of technical content in sets. Perhaps you will also be able to advance the state-of-the-art in LEGO Pneumatics technology! Mark

I might end up with one to build and another to begin the pneumatic experiments and turntable evaluation. I did the same with the Crawler, to evaluate the motors. There's no addition of the 2nd set to the 1st, like the snow plough of the Unimog, though a tipper trailer could be built with the 2nd set. I think Technic panels and studless construction help to reduce that, compared to a brick-built truck cab, by reducing weight. There's not much room for extra springs in the front suspension. If it still sags then maybe it's too well built Perhaps if the Arocs had a single front axle then single springs would not be enough on that. Also a good job the engine is so light Mark