Wiseman_2

Ah, to clarify, the string is tied to the base of the third section, so the length is fixed and it can't slide back. Might be a good idea to have a look at the instructions for the boom of 42009, which uses strings with studs to achieve the same thing. Sorry, I have no plans at this time - I haven't created instructions before and it's just not something I have time or priority for right now. I have some smaller MOCs I'd like to share which I might try doing that for, and if they work out maybe in the future I will (no promises though).

Wow... I'm honestly a bit stunned. Thanks to everybody who voted and participated, and to @Jim and @Milan for organizing, lots of seriously good entries.

Thanks! Incidentally, 8460 is my favourite studded set too, and one of only two from that era I still keep on display. It does indeed have suspension and a gearbox - when doing some research on mobile cranes for the build, I noted many have much more interesting features that don't normally ever get replicated in Lego cranes (normally being reserved for sets like the Mercedes G500), like selectable drive axles, diff locks, hi/lo range gearboxes and so on. I couldn't fit all that in at this scale but I could at least make it more interesting than the norm. I don't have instructions I'm afraid, I've never actually made them before. I'm on a bit of a break from building for now while I reorganize my parts collection, maybe I could trial some for the boom on its own... The third stage extends using a cable-return (I'm not sure on the technical name for it, if there is one). A single piece of Lego string is attached at the top of the yellow outer boom, which then threads down through the second stage to the base of the third stage, and back up onto the top end of the outer yellow boom. As the second stage extends, it pulls the string up and extends the third stage. That probably doesn't describe it very well, this photo might help: You can hopefully see the black thread that I'm talking about, it's similar to what's used in 42009.

Voted. Some really great entries, I do like that every entry is considered rather than just picking the standouts (mostly because there are too many standouts).

3-Axle Mobile Crane Functions: Steering on 1st and 3rd axle with proportional angle on 3rd axle, and working steering wheel in cab I6 engine driven by differential on 2nd axle, with 4 speed gearbox (gear shift stick located in cab) Full suspension on all 3 axles Simultaneous outrigger horizontal extension Simultaneous outrigger vertical deployment (capable of lifting crane off the ground when not horizontally extended, and stabilizing the crane for lifting when fully extended) Boom raising via XL LA 3-stage telescopic boom, with ratchet mechanism for locking, extending to a maximum reach of 108 studs/86.4cm, with vertical reach of 93cm Winch with ratchet lock 360 degree superstructure rotation Opening doors

Final photos all done now. Ideally I would have taken it over to my brother's (he has a great setup for Lego), but in this case my desk will have to suffice as a backdrop. And some additional photos: The outriggers, if not extended outwards, are capable of lifting the entire crane off the ground: More photos can be found on my Flickr.

One last update as the build is now essentially complete (I'm on mobile so hopefully the formatting isn't screwed up): After much testing I managed to get a 3 stage boom that fits neatly into a 5x5 cross section (plus some sticky-out bits to support) and works without error, extending to a maximum length of about 108 studs. I'm quite happy with the yellow contrast against the blue as well. Boom extension and the winch both use ratchets and friction brakes instead of worm gears, which makes them much faster and more satisfying to operate. The XL LA for raising the boom and the boom extension are controlled from the right hand side of the superstructure, while the winch is controlled from just behind the superstructure cab. I basically have no time left for any more building at this point. I'm going to try get some better photos taken on Sunday when lighting in my apartment will hopefully be better...

I'm hoping to have a 3-stage boom; I have a previous design that's quite compact, but would maybe look too bulky for this scale with only a 3-axle crane. I'm using the curved 3x11 panels for the main section in yellow (the only colours I have of this part in the quantities needed are yellow and red). Yes, it's to shift between 4 engine speeds. The four ratios (using Sariel's gear ratio calculator): 1st: 1:4.38 2nd: 1:2.62 3rd: 1:1.46 4th: 1.14:1 Hmm, thought I had a photo of the steered axles kicking around, apparently not... here's roughly how they're designed: There is a 3x5 thin triangle and a 3x3 T-beam that connects the two perpendicular crossblocks to the red one, which in turn supports the steering shaft. It isn't perfect and is the 7th or 8th iteration, at which point I decided I just needed something that would work. Can't promise anything I'm afraid, I did used to replicate my builds in LDD but time is a very precious resource these days! I will see how the final build ends up.

So, I’ve decided to give TC27 a bash, mostly just with the aim of finishing an entry (given that I failed to complete anything the last time I tried with TC25… for a MOC that ultimately ended up being fewer than 200 parts). My original idea was for a 3 axle truck along the lines of 42070, but after some rough proof-of-concept builds proved that the concept I had in mind wasn’t going to work - not least because the tires just didn’t suit - I decided to pivot to my backup plan: a 3-axle mobile crane. I wasn’t quite sure how happy I was with the build’s progress until I had the cab built, so the carrier is already essentially complete. The last large MOC I completed (not posted anywhere just yet) was a 7-axle mobile crane, also built using this wheel/tire combo. That one was of the ‘one motor/many functions’ variety, this one is going to be all manual, with some different features that I don’t normally see in mobile crane MOCs at this scale (I’m sure somebody will correct me if I’m wrong). So far the carrier has the following functions: Steering on 1st and 3rd axles with working steering wheel, controlled from rear; the 3rd axle has reduced steering angle compared to 1st axle I6 engine driven by differential on 2nd axle, via a 4-speed gearbox controlled from the cab Suspension on all 3 axles Outrigger extend/retract Outrigger raise/lower Some more photos of the carrier thus far: Here you can see the suspension. It has quite a lot of travel, necessitating the slightly higher wheel arches. The cab interior. The 3l axle with stud is the gearshift; in the back, the 16t gears run from the gearbox to the engine, while the 20t gears run to the steering wheel. With outriggers deployed. Extension/retraction is controlled by the 12t gear behind the cab, while raising/lowering is controlled by the 12t above the right-hand wheel arch. The engine is also visible behind the cab. And a shot of the bottom of the carrier. The gearbox was an idea I had later in the build, when I realized that there would be space for a single-layer, 4 speed gearbox underneath the cab; in bigger cranes, the cab normally sits lower, and so that space would be occupied, but here the cab sits a little higher and so the gearbox - and the drive for the steering wheel - can sit in that space without looking too obtrusive. I'm still not sure on the colour scheme just yet. I’d like the whole crane to be blue, but the boom is going to have to be yellow as I don’t have the parts in blue. I may look at 60324 and go with something similar for the superstructure, rather than making the whole thing yellow.

Well, somebody had to try it, right? I figured that since images are out in the wild and it's due for release in August, it's fair game for this contest (at least I hope so!). I've been in a bit of a slump lately with building (my ongoing project has been on hold for a year) as I don't have much time for it these days, but with this contest focused on smaller builds I think I can get it together. I've started with some ideas for the carrier first. As a tracked vehicle my options for a smaller scale were basically either the 3L track links, or going even further and using the 1L chain links (not accounting for more unorthodox ideas like the older rubber treads). Anyway, as they say, go big (or small?) or go home, so i'm using the 1L chain links. Keeping it small also increases the odds that I actually manage to finish it (that's not down to the deadline, that's down to my bad time management). The first carrier (top right) is essentially a 7x7 square. It's quite robust for its size, but isn't exactly proportioned well to 42146. I did try using the 8T gears first, but they don't mesh well enough with the chain links to run properly; the 16T probably matches better to the set anyway. The rest are all 9x7 with varying degrees of rigidity. I'm not keen on using the idler 16T gears as they don't feel as secure, and for some reason require an extra chain link vs. the standard 16T gears, but when the chains are added they look cleaner (with the half-width lift arms) than the standard 16T carrier, which uses 9L beams: I will probably go with one of the 9x7 carriers as they'll probably scale better. They're ultimately all sturdy enough for this scale (and deliberating over tiny things like this is why I keep hitting walls when building...).

19. 8460/8431/8438-B Truck with Knuckleboom Crane - Studless Original Set: 8460/8431/8438-B Knuckleboom Crane Truck Functions: Front wheels steered via the roof light Individually controlled left and right side stabilizers Crane rotation via gear on left side Two stage crane, with pneumatic switches on the left side, with the pump mounted horizontally between the rear axles and activated by a lever at the back of the truck Mini piston engine and spinning fan driven by dual rear differentials Discussion Topic: Photos: Some comparisons with the original model:

Thanks for your comments everyone :) I didn't take many photos of WIP for this one as I normally would, because I'm a pretty slow builder at the best of times (my last project took 18 months and I still haven't shared it yet), so I wanted to focus on the build in the little time I had. The only photos I did take in progress were before I made substantial changes, so I would know what to revert to if the change didn't work... so the only WIP photos I really have are of elements that didn't actually make it into the final model. Fortunately the bed is easy to lift up, so here are a couple of shots to show how the pump is connected. You can also see on the left the worm gear mechanisms for the stabilizers and the turntable rotation, and the blue hose that connects to the pneumatic switches: The yellow 1x4 liftarms are connected to the top of the pump, while the grey beams are then connected to the lever at the back. The white beams then stick out at an angle from the back of the bed as the lever that you press. I would have liked them to remain flat but the only way to get this to work and keep the pump beneath the bed was to have the switch at an angle (I tried a lot of different things and was very close to just having the pump sit upright in the cab). This side-on shot shows how the linkage is connected: It was a rather tight squeeze and there's exactly enough room for the swing of the pump that it doesn't touch the 20T gears connecting the differentials. The pneumatic hoses are routed under the turntable in pretty much the same way they are in the original, and like the original, there's really very little room (I always underestimate how much space is needed for pneumatic hoses) - unfortunately the structure almost completely blocks any view from outside, but there isn't much to really show inside other than the hoses anyway: And as requested, here is a shot from below: This probably doesn't show as much of the internals as you might have hoped, because there are frames from front to back. I had thought when making the studless conversion I would have used 6 to 7 studs for the center of the chassis, but the new tires were too wide, and so it's actually 6 to 5 studs (at least at the axles) and consequently relies on beams running across the top and bottom of those frames for structural stability. At the front you can see the 20T gear that drives the engine; it is mounted just in front of the axle as placing it at the front of the vehicle (like most sets) would have extended the whole front grill and subsequently looked a bit out of proportion. Yes, I did try a few different methods here, but the cams are necessary as the beam in the original is 10.5 studs long, and those cams were the best way of achieving that here. They are sturdier than they actually look and are well braced; maybe it wouldn't be sufficient on a more heavy-duty build but they are more than sufficient here. I think if I had more time I would have tried to find a solution that would allow it to fold without the half-stud offset.

It's been a long time since I've entered a contest here, but when the theme was announced I just couldn't resist giving it a try. The model I've chosen is something I've wanted to remake for some time and this contest was a great reason to push it up my project list. I did briefly give some consideration to other sets (notably 8414, which was the first Technic set I ever got), but in the end I decided to go 8460/8431/8438-B - the first appearance (as far as I am aware!) of a knuckleboom crane in a Technic set. Trucks with cranes are a staple of Technic, but there have only ever been two folding knuckleboom cranes as far as I am aware (I'm sure somebody will correct me if I'm wrong), and the original is one of my favourite B-Models. While I would have liked to get this topic going to show WIP earlier, I honestly had no idea if I would find the time to finish it (working in a hospital in the middle of a pandemic will do that for you). The model is now pretty much complete though, so here are a few preliminary photos. I will hopefully get some more cleaned up photos ready for entry (emphasis on 'hopefully'). I decided to go with the new tractor tires for this as they fit perfectly with the model's aesthetic. They are slightly larger than the originals, but I managed to keep the scale more or less the same because the tires on the original actually feel a little small. The model's functions are identical to the original, including in their geometry (which was a real pain to get done because there a half-stud offsets everywhere): Front wheels steered via the roof light Individually controlled left and right side stabilizers Crane rotation via gear on left side Two stage crane, with pneumatic switches on the left side, with the pump mounted horizontally between the rear axles and activated by a lever at the back of the truck And one additional function that is pretty much standard on every truck these days: Mini piston engine and spinning fan driven by dual rear differentials The original model does include an engine of sorts, but it is non-functional and only for display. The pump was particularly annoying to fit in, since in the original it goes right between the two rear axles. Here, it is mounted above them to allow space for the differentials, but this meant there was less space for the lever that would move the pump. It therefore uses a linkage to allow for the full pump stroke in a more compact space. I was not sure whether to go with panels or not. The rear bed would definitely use them were it to be built today, and there really isn't any way to replicate the brick-built sides of the original in a clean way using studless building; I've therefore added doors and a hood to the engine, which I think completes the looks a bit better. Some comparisons with the original model: I tried (successfully I think) to retain the aesthetic of the original engine, while also making it fully functional in the same space as the original. There have been some really great entries so far (as there always seems to be). I'll try get a few more photos up and get it entered.

This is the first contest in a very long time that I think I'll enter, some really good models so far. One (possibly dumb) question: are the B (or C) models of a set okay to enter with? I've had an idea floating around for some time that I want to try building that will (hopefully) be perfect for this.

Summer set names have been listed on Brickset: 42068 Fire Rescue Vehicle 42069 Extreme Adventure 42070 6x6 All Terrain Tow Truck