Off Road Knuckleboom Truck


It was time for another truck! Free instructions can be found at Rebrickable.

I have been building a lot of tractors and construction vehicles lately. I love building them as they offer a lot of movement and features. But it was time to build another truck. LEGO truck MOCs are beginning to coalesce around the “Mack Anthem standard” which is a 15 module wide truck in about 1:20 scale. Many MOCs are being designed in this scale as it is a good playable size, and fits the scale of some of the more recent LEGO trucks that have been released. I wanted to offer another truck in this scale, with some fun playable features.

I started with a chassis that uses a simple pendular suspension on the rear axle, which is damped by 2×1 rubber connectors. The rear axle drives a simple I3 fake engine under the cab through a two speed transmission. The transmission changeover is on the right side of the truck. Front steering is controlled though the HOG light on the top of the cab.

I have found a simple way to add a three way tipper bed in my trucks, and I have used it many times before. A mini linear actuator moves simple linkage under the bed that can pivot in three different directions. Each corner of the bed has a removable axle that allows control for which way the bed tiles. But in the past the control for this tipping function was in a tricky place to reach, so I wanted to route the control to the top of the cab. I managed to add this right next to steering light. I used a top pivot design on the bed sides and rear, locked by a 3/4 pin on the bottom.

Finally, I added a crane, and since I had a little space left over, two stabilizing outriggers. The outriggers are a simple two link design that are controlled with a worm gear mechanism. The crane is a little more complicated. It is mounted on a small turntable with a rotation control on the left side of the truck. The first lift mini linear actuator is controlled by the third HOG on the top of the cab. The second lift stage is controlled by another mini linear actuator. Finally, the third stage has an extending boom that allows the reach of the crane to extend a little more. The crane can lift some; not a lot, particularly when the boom is fully extended. By removing the three HOG knobs, the cab tips to show the engine. Also, both doors open.

I loved the way this trucks looks. The beefy tires, and the cabover design give the truck presence and look of toughness. The crane was a lot of fun to play with even if it could be a little stiffer. However, this may be the last time I use this three way tipper design. I am happy I moved the control to the top of the cab, but the linkage does not have the power it needs at the start of the tip. I will have to come up with something better for the next truck.

Stay tuned, and happy building until then.

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John Deere Axron


What started out as a little tractor and trailer has grown into the Thirdwigg Farm! And it needed a bigger tractor.

Free instructions are available at Rebrickable.com.

I started with a simple, small, row tractor that I called the Atmos. This tractor was mid scale and in addition to steering and a fake engine like most of my builds, it featured a front implement mount, rear three point hitch, rear PTO, and rear Pneumatic PTO. Little did I know how the tractor would grow into a lot of other tractores, trailers, impliments, and farming support vehicles. At some point, I found myself interested in making a larger tractor, and I have always loved the Claas Xerion. The Claas been done in Lego Technic before, so I went the John Deere styling route for my build.

The tractor had to integrate into the other builds, so the front and rear mount and PTO placement dictated a couple of the hard points. I built the tractor with four wheel drive, and four wheel steering. A four cylinder fake engine is placed under the frond hood above the front axle. The rear most cylinder does not move as the crankshaft would have run into the steering unit, and any change I tried to fix it made for an ugly hood. A worm gear actuated rear three point hitch allows for implements to be mounted to the tractor.

The steering is controlled by a HOG light at the top of the cab, which caused some headaches for placement as I wanted the cab to be able to rotate. There is a small gear on the right of the tractor that controls the rotation through and internally mounted worm gear. Getting the cab to rotate in the right spot, without hitting anything, and while still having the pneumatic pump, required endless test rotations.

Since this is a Thirdwigg Farm tractor, there are many options to pair with this tractor, all with free instructions. My favorite is the Hookloadr trailer, but the Tandem Disc looks great too. Free instructions are available for all the options, so feel free to make your own farm.

It is always fun to make another tractor and this one was no exception. I wish the drivetrain was a little more smooth, but the rest of the tractor worked flawlessly. And it looks fantastic. Coupled with a trailer, makes it look strong and purposeful. And the rotating cab is so much fun to play with. We’ll see what gets added to the Thirdwigg Farm next!

Happy building!

LEGO 42136 Articulated Dumper


I have never made an alternative model, until now!

The popularity of alternative models has been increasing in the past couple of years as Rebrickable has allowed for an easy way for people to see what they can make from the sets they own. I tend to be more interested in making the machines I want, but I figured I should learn how to do an alternative model at some point, and this summer I was ready for a little challenge.

LEGO set 42136 is a decent little set with some simple functions and an accessible cost. After I purchased the set, and put it together, I thought about what I could turn it into. Making an alternative model means you need to think right away about the special parts you have how they could be used in another MOC. For me, the important parts were the yellow panels, the turntable, and the wheels/tires. I wanted to keep the yellow and green well integrated, otherwise the build would look messy. Going through my Pinterest account, I came across the Hydrema Dumper, and I immediately knew it would work. I got to work.

I made a draft with the tires, bed, and major panels placed. Then it was just build, rebuild, rebuild to make sure all the parts were well supported and color matched with the parts available. Sometimes I just wanted another simple connector, and I had a use another solution with the parts I had left. Looking over the remaining parts, I wish I would have used the gears, and the little tires from the trailer. The tractor finished with steering and a tipping bed, and a cute little face.

I was happy to finally do an alternative build. This one looked clean, and the functions worked well. There has been some interest in the MOC, as some people have already built it themselves. You can too! It was a fun little challenge, so I’ll make some more alternative builds in the future.

Until then, happy building.

Skid Excavator


Another little contest build, complete with Free Instructions.

I participate in a number of LEGO Technic contests, and Eurobricks hosts a number of them. The requirements for the TC22 Contest was to build a Technic construction vehicle that could fit in a 10,000 stud bounding box. It had been a while since I built an excavator, and they allow for a lot of functions in a little bit of space. I have always been intrigued with the machines built by the French company Mecalac, and after looking at their cute little Skid Steer Excavators, I had my subject. Setting the scale was important as I only had so much space. I decided on the large tracks as I think they look a little better. Setting the width with the tracks at 17 studs, would give the stability needed, and would give me some working space. Calculating the rest of the excavator would allow for 28 studs in length, and 21 studs in height for a total of 9,996 total cubic studs.

I stared with the boom, which is a little complicated. The boom is a 3 section design, and should reach far, and tuck in close to the front plow, and be able to dig deep. I planned the movements with mini linear actuators, and wanted to keep the controls easily accessible. This resulted in a design where two actuators had controls on the boom, and two actuators had controls on the back of the superstructure.

I thought I had the hardest part done one the arm was finalized, but I quickly discovered that the rest of the superstructure was going to cause some problems. First, I was not sure on the shape I wanted. It took a couple of drafts to get the rear shape right. Once I did I realized I had some space for a little engine, so I added this, and connected it to one of the boom lifts. Now a little engine turns when the arm moves. Once these features were done, it took another four drafts to make sure the tractor would not fall apart.

Then off to the cab and the attachments. The can was simple enough, with a simple chair and the HOG mounted to turn the superstructure. I created four different attachments, including two excavator buckets, a skid bucket, and a set of forks. In what is becoming a standard feature of my builds, each can be changed over by pulling a couple of axles on the boom.

I was pleased with how this build turned out, and it was good enough for a third place in the Eurobricks contests. All the attachment options made for a fun, playable model, and the movement of the boom was perfect. Feel free to build one of your own.

Happy building.

End Loader


Time for another Eurobricks contest! Free Instructions are available at Rebrickable.com.

Another Eurobricks contest was made available, and this one was right up my alley. In fact, I was so excited about the contest, I made two MOCs. The contest was to create a small, less than 10,000 cubic stud, construction vehicle. I figured an end loader is perfect for the contest theme, and it was a while since I created one. I build a quick draft of the shape including where the steering, engine, and bucket would go.

At this scale I decided quickly that adding an engine would be a great feature, but four wheel drive would only distract from the look and the function of the bucket. The engine is a little 3 cylinder unit that is mounted transversally behind, and powered by, the rear axle. This placement allowed for steering and bucket tilting to be placed in a HOG placement.

Drive Mech

I next worked on the linkage for the bucket. It took a couple of tries, but I finally got a linkage with full movement. Two mini linear actuators are placed on the side of the loader for bucket lift, and are linked together. The manual control is a small gear on the left side. The bucket tilt uses a Z-linkage design that allows for the bucket to move correctly through the lift movement and not dump any load. This is controlled by a single mini linear actuator, with a controlling gear on the top of the engine cover. The head of the bucket allows for quick change between a bucket and forks. Finally, steering is controlled by the HOG on the top of the cabin, and keep my high standards for steering feel with low slop.

I was pleased with this little creation, but it was not as interesting as the other MOC that I designed. So while everything worked well, and looked great, I submitted the other MOC for the contest. I hope you enjoy the MOC, and feel free to build one of your own.

Happy Building!

John Deere Scout


Another addition to the vastly growing Thirdwigg Farm.

I built the Atmos Tractor a couple of years ago as a small little project. Soon I had created a number of attachments and trailers to work with the tractor, and soon I was more tractors and other machines were added. But the balance needed some additional tractors, so I decided to make a little partner.

The John Deere Scout specifically so I could use the new Tractor tires that came from Lego 42122 and Lego 42129. But I wanted to it to be a smaller tractor with many of the features needed for full Thirdwigg Farm integration. Thus, the tractor had to have the common front and rear attachment points, a rear PTO, and steering because I put that it everything. Soon it was clear that the size of the tractor was going to make a fake engine poorly done, so I left it out. But I wanted some other feature to make this tractor unique.

The front bucket uses a worm gear function to lift the front arms. It is driven by a mechanism that drives rear, and then up to the top of the cab. There is a little gear for the HOG function that is just behind the steering HOG. A small worm gear mechanism is used to tilt the bucket. The arm can be easily removed if the desire is for the tractor to mount something on the front attachment point. The rear PTO is connected directly to the rear differential, and the common three point hitch is installed as well. Finally a trailer hitch is attached.

I also made a couple of attachments specifically for this tractor including a snow plow and scrapper, and a little trailer. Both may be found for free at Rebrickable.

With each additional tractor I add, I think it will be the last, but I keep having more ideas, and each one has been fun to design. I was pleased with how this tractor turned out, and how well it functioned. The tires look great at this scale. Most importantly, it matched well with each of the other tractors. The instructions are freely available at Rebrickable along with all the other Thirdwigg Farm builds, so feel free to make one of your own.

Happy building.

Synthe Combine


It was time to build a combine harvester for the Thirdwigg farm.

You may find instructions for this model at Rebrickable.com.

I was putting off building a combine for a while because they are pretty complicated. It took me a while before I felt like I understood enough about them to translate them to a LEGO MOC. After some time learning about them, I was ready to begin something. The scale was set based on the Atmos Tractor, so then it was a matter of deciding how many features I could add into the model. The models started with the thrashing mechnism, and then everthing fit in around it. I settled on a rotating thresher rather than a set of shuffling screens. In the center of the combine is a rotating auger that separates the grain from the staukes. As the auger spins it move the crop rearward separating the grain as it travels rearward. In the MOC, the auger is connected to the front wheels as the combine moves. Under the auger is a reciprocating screen that further separates the grain. Likewise this is also connected to the front wheels. At the rear of the auger are two spreaders that spread the chaft out the back of the combine.

Also connected to the front wheels is a takeoff that operates one of two cutting heads. The cutting head uses two augers on each side to move the corn to the center so it may be driven into the combine. A cutting edge is right behind the cones, and its movement is driven by a link below the combine, so it may cut back and forth. The full corn head is removable, and can be easily replace with a grain head. Each head is mounted on a moveable mounting plate, which can be moved up and down for harvesting and transportation.

In addition to the harvesting functions, the combine also has an opening right side so you may see the internal functions of the tractor. Here you may also see the mechanism that opens the top hopper. Additionally, the grain extractor on the left of the combine can be extended. Steering for the rear axle is operated by the air intake on the rear of the body.

This MOC took more time than usual for me, and there were a couple of times that I thought about scrapping the build, but I am happy I stuck with it. In addition to having another vehicle to populate the Thirdwigg Farm, the functions of the Combine were fun to implement in this build. Each worked well, and were fun to play with. The interchangeable head was an addition that changed the look of the combine depending on my mood, and each functioned well.

I guess it’s time to plan another tractor. Until then, happy building!

Unimog U400/U430


I frequently build another Unimog after it has been a couple of months since the last one, so here is another TWO!

You may find building instructions for both the U400 and the U430.

I generally find myself building a Unimog about every year, and this year, I built three. Kindof. Early in 2021, I built a Short Wheelbase U500 in blue, and I loved it. So, I wanted to see if I could take the build a little further. I’m partial to the U500, but the U400 seems to be a little more popular, and the current U430 was another challenge I wanted to try.

Instructions available for both.

The chassis for both is a modification of the U500. The wheelbase is 2 studs shorter, so I removed the winch and the PTO on/off switch, and modified the bed tipping mechanism. The rest is the same, including the front and rear PTO, the four wheel drive, and the I4 engine. Both the U400 and the U430 have a manual pneumatic pump with a front/rear switch for attachments.

The tipping bed is the same for both, and can tip in three directions. The three sides drop as well. And the cab for both is generally the same, with a slight change to the front to address the styling differences for both. You can see the similarities between both in the videos below.

I’m pleased with these MOCs, and how they worked. The U400 is the most beautiful MOC I have made in a long time. It currently adorns my desk at work, and will continue to do so for some time. While I wish both would have portal axles, the stability of the drivetrain, and the flawless reliability is worth tradeoff. The U430 looks great as well, especially with the tires, the orange is my favorite. Hopefully I am able to make some attachments for the front and rear. Stay tuned.

Until then, happy building!

8854 Update


Winner, Winner, Chicken dinner is what we say in my house!

Free instructions are available at Rebrickable.com.

LEGO 8854 Update

I often participate in online LEGO contests, and most of them are on Eurobricks.com. In the summer of 2021, Eurobricks announced TC20, Technic Studless Recreation. I participate in many, but not all, of the contests that Eurobricks offers. The requirement was to pick an old studded set, and recreated it in studless Technic. I couldn’t sit this contest out, as it checked all the right boxes for me. Entries would be smaller to stay in scale, the builds would be feature packed, and it they would have a deep nostalgic connection. I was in.

Choosing a set to recreate took some time. I started with a list of 32 sets, and started to whittle it down from there. Quickly I removed some of the sets for various reasons: interest, size, not right now, too sacred (8880). I ended with a top three of 6357, 8855, and 8854. 6357 would be interesting to me, but after doing 8640 a couple months back it could wait. 8855 had some opportunity. It is a classic set, and instantly identifiable. I built a little mock-up, and let it sit for a couple of days. I didn’t come back to it.

I am not sure why I did not settle on 8854 right away. I love building Unimogs, and when I do updates I like to add some features. 8854 was missing suspension and an engine, so everything was right for me to recreate this iconic set. I had made my decision and I started posting my progress. First, I had to decide the scale. I made the decision to use the newish Batmobile tires in the build, which make the tires a little larger than the original 8854. I added a stud to the wheelbase to compensate, but otherwise the scale would remain the same.

Next, I had to figure out how to add all the features I would want, while keeping all the original features. HOG for the steering would remain on the top right side of the cab, naturally as a beacon. I then added a control gear for the outriggers on the top left side of the cab. The rotation of the crane would be on the right of the truck driven by a worm gear, and all other crane controls would be on the crane itself.

Fitting in the suspension and engine was a little tricky. Adding the engine was simple enough. There is a differential on the rear axle with portal axle. The driveshaft goes forward to drive a I4 mini engine. Suspension is a dual pendular axle setup: both axles pivot side to side. The front and rear axles are linked together so that when one axle pivots right, the other axle pivots left. It is a simple design that functions well.

LEGO 8854 Engine

Designing the crane was the easiest part. Panels form the base of the arm, and a simple extending boom as created using studded technic beams and some rack gears. A worm gear extends the boom.

The cab is where I had some trouble. 8854 has a funny shaped cab to my eyes. First, it is very narrow. Second, the hood slopes very steeply. Third, the windshield is not very steep, more car shaped than truck shaped. I rebuilt 8854 in Bricklink Studio to help me compare the two designs over each other. I found this to be a helpful step, and allowed for some good feedback from other Eurobrick members. I ended up making the hood a little more flat and slightly shorter. The roof was made a little longer, which made the windshield a little more steep. Then added the fenders that wrap around the wheels a little better, and headlights and a grill that referenced the original grill. I was pleased with the final design. Oh, and I added seats, opening doors, and a dashboard.

Being able to compare the two versions side by side helped me feel comfortable with how the build was going. Most of the time I use Studio when the build is complete, as do not like to tinker in Studio. However, being able to see changes in real time, was immensely helpful. I could ask was the new version staying true to the original? If not, what was the specific part that was making it feel/look off? Being able to overlay both versions on top of each other was helpful, and a step I will do again in the future.

Cab Comparison Overlay

It turns out the design was good enough for a first place! I was thrilled that through both a voting and jury stage, this update was picked over 46 other designs. In addition to that affirmation, I was pleased with how the MOC turned out as well. The functions all worked well, and the control of each was simple and effective. I only wish the suspension was little more stable, but this was only noticeable when the crane was fully extended. I’ll use the suspension again in other MOC soon. If you love 8854 as much as I do, I hope you will give this update a build as well.

Happy Building.

Compact Telehandler


Sometimes I plan out a build, and other times, a build just kind of happens. This was the latter.

You may find free instructions for this MOC at Rebrickable.com.

After building the Atmos Tractor, and then a gazillon implements, attachments, and trailers, I started branching out to other machines that could be used at the Thirdwigg Farm. The Compact Loader was a result of this. I was playing with the new LEGO 42122 tires, and quickly came up with a little four wheel steering idea. I added a fork boom, and decided to see where the project would go.

I am quite fond of LEGO 8283, and the rest of the design was influenced by this little set. I tried a couple of boom extension designs, but each looked a little too “overweight” for the little tractor. So I came back to the extension design that was used on 8283. A mini linear actuator is used to lift the boom. Both functions are controlled by two separate gears on the back of the telehandler.

The cab came together pretty quickly, though I had to make sure the new tires had a clear range of motion. I added some lights, and front fenders which brought a little visual weight to the front. I had a tricky time finding rear fenders that I liked, but I eventually found a solution I liked. In my move towards increasing the readability of my instructions, I have published a PDF with step-by-step instructions that list required parts for each step. I hope they are clear for you, and they bring value to your own build.

The Compact Telehandler worked just as I hoped. The steering is great; it’s fun to drive this little tractor around on a small desk. The boom lift works well, and has a great range of motion. The extension works smoothly, though since it is driven by a worm gear, if the extension is in the wrong position while trying to lift the boom, the boom will bind. The fork tilt mechanism is smooth, and is easily accessible in all boom positions. We will see what next build come from just playing with a couple of parts.

Happy building.