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!

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!

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!

LEGO 42126 V-8 4×4


Sometimes a LEGO set needs just a little more content. 42126 is one of them.

Instructions may be found on Rebrickable.com.

LEGO 42126 was introduced in the Summer of 2021, and I was immediately drawn to the pickup as it included some features I like, such as steering, suspension, a decent (at least in the USA) price, and it’s Orange! But there were serious features lacking such as four wheel drive, a V-8 (I know, I know, a Raptor, and many of Ford’s F-150s use a turbo V-6), and the rear suspension geometry was weird. I agree with others, that some parts of the design like the rear taillights and the front headlights are a little off. But, like 8081, I saw some potential here, and I ordered the set.

In fact, before I even received my copy of 42126, I was designing and a building a new chassis. The V-8 was easy enough to add, as the space under the hood is extensive. Adding in a front drive axle was a little more complicated. To keep the width, steering geometry, and suspension travel the same as 42126, adding a front drive axle would take a little work. I used a floating differential design, which allows the differential to move freely as the suspension travels through its movement. The steering link was flipped upside down, and relocated in front of the drive axle. The suspension swingarm and shock absorber mounds did not change.

42126 V-8 4×4 Chassis

Immediately behind the engine firewall a differential that connects to the V-8, and the rear axle. The rear axle is changed to replicate a better movement of the rear Raptor. LEGO noted how the half module offset of 42126 was a feature they had to work on to get the placement of the axle correct. However, this feature was only needed as the pivot point of the rear axle was so to the rear of the pickup. By moving the pivot point of the rear axle farther forward, the travel pivots less, and creates a better axle movement of more up and down. This also helps place the axle better when one side is up, and the other down.

While I made no changes to the exterior, I made minor changes to the interor. The colors of the seats have been changed so they match one another a little better. Finally, with a little bit of cross frame bracing, the pickup was done. When 42126 finally arrived, I removed the bed, the doors, the hood, and the roof from 42126, and my F-150 was done.

I like making modifications of sets more than I like making B or C models of them. As such, this project was an enjoyable one for me. I worked fast, and I liked the improvements I was able to make to the original. I like the look of 42126, so keeping this consistent was fine for me, and the additions of the V-8 and the four wheel drive was a fun challenge to pursue. Now to see if I can do a Sport Truck version of 42126. Stay tuned….

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 Loader


It was time for me to learn how to do Bricklink Studio, and my Atmos Tractor needed a friend to load all of the trailers.

Free instructions can be found at Rebrickable.com.

This small loader came together rather quickly. I decided to use rear wheel steering rather than articulation as this would keep the mechanics of the bucket/fork simple. Additionally, I wanted to use the new tires from LEGO 42122, and they take up a little more room while turning. Finally, I wanted to allow the tractor to switch easily from forks and a bucket, so this simple feature was the second part to figure out.

The next part of the build required a little more trial and error. End Loaders are tricky in that they have a wide range of motion, and have to fit within a little given space due to the front wheels, cab, and ground. It become clear that at this scale, a mini linear actuator was not going to work. So I used a worm gear and 24z gear with a small linkage to the boom. This gave a wide range of motion, including a very high lift height. The motion was controlled by a 20z gear at the rear of the loader.

The bucket/fork tilt was a little more tricky. A 8z gear and worm gear control the movement. I add this mechanism in many of my builds because it works well for many needs; and it is small. In this build, I needed to redesign the frame for this mechanism as the standard build would not allow for the bucket and fork to fully tilt at ground level. But with a little modification, I was able to get it to work. At the high end, the bucket tilt can bind, which is not great. The tilt stays consistent as the boom lifts, which was a requirement for me as the fork was going to be a center part of the build. Control for the tilt is at the rear of the tractor. Pulling two axles allows for quick change between the bucket and the forks.

Finally, I built this MOC with the singular focus of developing my skills with Bricklink Studio; with the goal of improving the instructions that I make available. I have made photo sequencing instructions for years, but with the 800 pound gorilla that is Rebrickable.com, more and more people are contacting me directly saying some form of “I am confused when I try to build ______.” So, after trying a couple of 100-200 part builds, I launched into this Compact Loader, and built the file in Studio. Studio takes a little time to get used to, but it is slick. And the instructions that are generated are very slick.

But it does take time. Many of my instructions have been free, and I continue to value this for many reasons, but I’ll be reevaluating this the deeper I get into this transition. Either way, enjoy the many MOCs of mine that you can build for free.

I am pleased with how this MOC turned out, and what it taught me about building in Bricklink Studio has been valuable. The model fits my design language, and functions as I expect my models to function. And now, you can clearly figure out how to build it as well. I hope you will enjoy the build as well.

Happy building!

2C Sports Car


3T Sports Sedan was the inaugural car for startup Thirdwigg Motors, and the market requested another, smaller, sportier offering. The board of directors approved development of the 2C to fill this need.

Full gallery including instructions may be found here.

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I wanted to keep the scale and keep many of the best parts of the 3T in this design but change the body style and add a couple of features. Very early I decided on a two door with a mid or rear engine. I wanted to get a better transmission, so with this, I set of to work. I scaled the car to the Porsche Cayman, and started fitting in parts. I used the same suspension from the 3T in both the front and rear, which constrained how the driveline would have to be routed.

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It was at this point that the interior setup got a little complicated. When I started this car, the new Wave Selector was just release which optioned a lot of gearbox options. After seeing this great little transmission, I knew I had what I wanted: a four speed sequential transmission. After playing with some options, I place it in the middle of the car. I toyed with having the engine behind the rear axle, but settled on a mid placement. Nothing larger than a Flat 4 was ever considered. The four speed gearbox worked and a changeover axle ran to the front under the suspension where a simple rotation limiter was placed. The steering HOG and steering wheel had all of their mechanics in front of the transmission, so everything fit.

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I had intentions of having a ratcheting gear selector to work with the slick sequential  transmission. But I was running out of space. The center of the car was taken up with the transmission, suspension at each end, and placing one in the rear did not give a way to connect to the transmission. So the only place left was under the front hood. There were a number of great change over options that work well. I tried each. Some fit, some worked great, but each had the same problem: there was not good way to seamlessly integrate the “button” into the bodywork. I had visions of pushing on a grill to actuate the mechanism, but the grill was not very big, and required even more space than I was already using. In the end I decided to scrap the idea of a changeover, and use a simple rotary selector. It is not fancy, but it works well, and keeps the bodywork clean.

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Through out this process I was toying with ideas for the body work. Generally, I add parts as I like them, and when everything is placed, I rebuild the whole car with structures in place for all the final placements of critical internal and external parts. But this car had a large transmission in the middle which meant there was no frame running from the front to the rear. I added a structural frame under each door, and tried to build up the frame under the transmission as best as I could. It works, but there is still a little car flex under heavy center load.

First, the bodywork on this car works better for my eyes than the 3T, even though I tend to like sedans a little better. Second, the gearbox worked flawlessly. It was smooth, and even though I had the open the hood the change gears, the smoothness was worth it. Finally, the suspension worked great as it had proved itself in the 3T. It now adorns the desk at my work. Hopefully you enjoy it too.

Don’t worry, Thirdwigg Motors is already hard at work on the next car.

Happy Building.

Porsche 911RS


There is a part of me that finds LEGO 42098 a little gimmicky: buy this truck that fits 5 cars but comes with 1 so you you build or buy more to fill the truck. But, these wheel arches are so awesome that I am going to do just that.

Full gallery including instructions may found here.

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After a rough first draft it was clear I was going to be able to steering and a Flat 6 into the car at a scale that would work for 42098, so most of the early work was on figuring out the shape of the car. I knew the car was going to be orange, and I wanted the little ducktail spoiler, so I modeled the car after the 964 version of the Porsche 911. The rear differential is placed two studs in front of the rear axle to allow for more room for the rear engine. I kept the normal LEGO engine parts rather than an axle engine like in 42098. The steering is simple in all in front of the driveline.

911RSDrive

The body work continued to take the most time. I used a great 911 MOC from Paave for many ideas including the seats and the front hood. Eventually, it all came together, after a lot of work on the doors, the roof, and the rear deck. The 911 is a beautiful car and getting all the details is so tricky. I almost feel bad for how critical I was of LEGO 42056. Almost…

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One thing you will notice is my use of both the 43mm and the 49mm tires for the rear of the car. I go back and forth on which ones I like best. Also, there was no way is was going to use the skinny 43mm tires for the front. They look silly.

This little car worked great, and functioned as intended. The shaping was off a little particularly with the rear quarter panels, the roofline, and the front headlights. But the shape of the 911 is so iconic that get all the details that have been refine over 50ish years is tricky. Either way if fits on the back of 42098.

Happy building.

Unimog 437


If my previous builds are any indication, I am a big fan of Unimogs. So it was just a matter of time before I built another one. Rather than building one this time, I built a modular system that allows for a number of different versions.

Full instructions can be found here.

This build started with a desired to make another small build with the great Fischertechnik tires I acquired. I wanted to build something small and playful like RM8s FJ or Sheepo’s Defender. As has been happening with many of my recent builds, I wanted to give the MOC some playable options and easy modifications. A Unimog was a perfect option, and who am I to turn down a Unimog? So I gave myself the following constraints: 4×4, I4 fake engine, steering, manual and PF drive options, removable cabs, removable bed, and two chassis. I set off to work.

The axles came together fairly quickly. I decided quickly not to do portal axles, because I wanted the complexity of the MOC to be elsewhere. Both axles have a differential, two soft springs, and are stabilized longitudinally via steering links and laterally via panhard links. All for shocks are mounted on crankshaft parts to get the ride height of the Unimog just right. There is about 1.5 studs of travel for each wheel, which provides adequate articulation.

The axles are connected to a fixed axle that powers a I4 fake motor. Since I wanted the MOC to be easily switched between manual control and PF, the driveline got a little over-complicated quickly. The steering axle and drive axles cross each other twice. This allows for the steering to go to the top for a HOG, and backwards so a PF servo motor can be added. A 16t gear is available at the top of the chassis to power a PTO, or add a PF XL motor to give the Unimog propulsion. The long Chassis can fit a full a full Power Functions pack. When the power pack is not installed lots of open space is available for other additions. I added a three way tipper lift mechanism for both the long and short wheelbase chassis.

Attachment points were added for the rear bed and for the cab. I created three cabs, and each can be added to both chassis (though the Doka looks best on the LWB). Two axles with stop can be pulled to free the cab. I created three beds and a power pack. Four axles with stop are required at each corner to secure the bed. A camper and a crane bed are not far behind on my building queue.

The Unimog turned out exactly as I wanted. The suspension and steering are light and smooth under manual operation, and work great with PF. I am excited about the ability to offer and develop multiple beds and cabs. Instructions are posted, so I look forward to seeing other options people develop to make their own Unimog.