Unimog U90


About 3 months ago I purchased a set of four Fischertechnik tires from ebricks.ru. After seeing a review of them by RM8, I reached out to him, and he mailed me a set. After a little time, I finally have something to show with them.

Unimog U90

After playing with a number of ideas, I decided to do another Unimog. It’s easy to motivate myself to build a vehicle I love. This time, I wanted to do the unloved U90 (418) version. It was not a terribly successful version, as many find the hood…not one of the best. But few people have built this version, so I was up for it. I put to to a vote on Eurobricks, and the decision was to build it in green. Off I went.

The scale required a 27 stud wheelbase and a 19 stud width. I built the front and rear axles and tied them together. Through a couple of edits, I finally added the suspension and figured out how to get portal axles into the truck. The Power Functions XL motor was mounted just over and in front of the rear axle driving power to all four wheels. The Servo motor was placed directly ahead of the XL for the front axle steering. I added a four cylinder fake engine over the front axle. The rechargeable battery box was placed over the rear axle.

Unimog U90 Driveline

The suspension is a live axle setup, with four hard shock absorbers at each corner. Each wheel has about 2 studs of travel. Not much for a Unimog, but enough for a 418. At this point I started a draft of the cab, and a draft of the bed. At this point the truck had an identity crisis. Move forward with green or find another option.

Unimog U90 Bed Tilt

Building LEGO Technic with green is not the easiest. The color lacks 1×5 and 1×11 beams. Both of the these parts would be needed for the bed and the cab. I could make some things work for the 1×11 in the hood, but there was no other option (read, inexpensive option) for the 1x5s needed for the bed. I toyed with other colors for the bodywork; orange, white, blue, yellow. None of them had the right pop I was looking for. Other than the orange, but, as other have said, orange has been done too many times. Then it dawned on me, “why not use plates?” I had my solution. With one bricklink order, I was done.

The truck drives well, and is easily controllable. The front portal axle can use a little strengthening, so serious trial abilities are lacking with this truck. Both the bed and the cab can be easily removed. I ran out of space for a ram to elevate the bed, but it can tilt three ways. I was pleased with how the truck turned out. It looks great. The driveline coule use some improvements, so I will make those improvements on the next truck.

 

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Kalmar DCG180-9


After doing a lot of non powered builds, it was time for me to do something motorized. I very much enjoyed doing a forklift a couple of years ago, so it was time for another one.

See the full gallery on Flickr and Brickshelf.

Kalmar 180

The JCB930 that I did a couple of years ago was non-motorized and had some great features. I wanted to build something with all the same features, and since I would need more room for all the electronics, I decided early to model the forklift after the Kalmar mid-sized 180 model. The model would have drive, steering, a two stage lift, and fork tilt. I did not realize how hard this would be. I wanted to keep the  boom clear for visibility, and the forks not more than two studs in front of the wheels to keep integrity of scale.

Kalmar 180 Front

I set the scale and I went to work. After setting the chassis measurements, I went to work on the fork and boom. I knew I wanted to have a two stage boom, and I wanted to keep as much of the boom open as I could. The forks connect through the middle of both the first and second stage booms, and pinch both together. The middle boom is has a gear rack on both sides to lift the forks. This boom has two gears at the top, to route the chain over the top to move the forks. The outer boom is connected to the chassis at the bottom, and two mLA connect to it operate the tilt. After some working, I was able to get the boom to be thin, and just how I wanted.

Kalmar 180 Up

I decided early that I want to keep the motors out of the boom. So I had to route the lifting function out to the forklift body through the bottom pivot. This required routing the lifting axle under the drive differential. The lifting axle then move rearward, and connected up to a PF L motor. On top of the lifting axle was the drive axle. The PF XL motors was mounted transversally on the right side, and drove and axle forward to connect directly to the differential. To give me some additional space at the front, a portal axle was mounted on its side to move the differential rearward. A PF Servo was mounted in the rear, over the steering axle, and drove the steering function. The steering uses some 2×4 liftarms mounted at an angle to allow for a better steering angle. Finally, a PF M was mounted in front of the Servo, under the cabin to drive the tilt function. None of the mechanics were difficult, but the packaging required a number of drafts.

Kalmar 180 Open

The final hurdle was the body work. I spend a lot of time early in my MOCs working on packaging placement, so I do not have many body work problems later in the build. Still, some simple SNOT work was needed on the side sills to fit about the battery box, and the XL motor. Oh, and the wires. The cab was pretty straightforward, but still took a little bit of time. Finally, I had some trouble with the rear engine cover and counterweight. In the end it was a simple design that I settled on, but I tried many designs. Again, this took a lot of time.

It took a long time, but I am pleased with the final product. The functions worked smoothly and consistently. The control that was afforded by the fork functions was great. It could lift three AA battery boxes at a time. The steering was quick, and had a great lock which gave great maneuverability. The XL motor provided adequate power, and moved the forklift well. Finally, the bodywork represented the original Kalmar well. I hope you enjoyed as well.

Until next time, Happy Building.

T-55A


The T-72 that a made a couple of years ago is still the most popular MOC I have made; at least in terms of internet analytics. This year, I committed to making another tank, so I figured keeping in line with old Soviet armor would be rather apropos.

The main gallery may be found on Brickshelf or at Flickr. Instructions may be found here.

T-55

The T-54/T-55 line of tanks have been produced in greater numbers than any other tank. The MOC represented here is a T-55A, representing types that were assembled starting in 1970. This series included an updated NBC and antiradiation system, an upgraded engine, and also added back in the 12.7mm anti-aircraft DShK on the loader’s hatch that was part of the original T-54 spec.

As with most of my MOCs, I starting scaling the tank before any building took place. I knew I wanted to use the newer, larger track links, and I knew I wanted to use the old mid-sized wheels. This set my scale, so I got to work. Starting with the chassis and the hull I worked first on the driveline and suspension. I used simple 2×4 liftarms to connect the road wheels to a suspension axle which activated a shock absorber inside the hull. Each road wheel has its own shock absorber. Fitting them all in took some creativity, but they are all mounted inside on the left and right sides of the hull. In the end, each wheel has about 3 studs of vertical travel.

T-55 Chassis

In between each suspension bank are the remaining mechanics.  After the suspension was set, I worked on the turret functions. Right from the beginning, I knew the tank would have a rotating turret and an elevating gun. It was clear having the elevation mechanics for the gun in the turret would be tight, so I decided instead to have the functions placed in the hull rather than in the turret. Using a vertically mounted mLA, connected directly to the breach of the gun, I was able to develop a method that would elevate the gun throughout the full turret rotation. The turret rotation was driven by a 8z gear connected to the turntable, and reduced by a worm gear. Both motors for the elevation and rotation are placed directly in front of the turret.

T-55 MechBehind the turret are two PF L motors mounted transversely side by side. They drive a 1:1 gearbox which connect directly to each rear drive sprocket. The IR receivers are placed above the gearbox. For those keeping score at home, the internals are (f to r) the battery box, the turret motors, the turret mechanics, the drive motors, and finally the IR receivers.

Working on the exterior of the MOC is what took the most time. The hull came together pretty quickly, with the exception of the details over each track. Most of the finishing time came with the turret exterior. Most Soviet tanks have the distinctive mushroom turret, which considering LEGO’s cube orientation presented some challenges. The turret of the T-55 also has a slight triangle orientation when viewed from the top. Like the T-72, I designed the turret with four side orientations (left, right, front, and rear), and one top orientation. Starting from the rear, I added a basic curved structure. The sides each had a couple levels of slopes, each tapering in toward the gun. The front was a little more complex. There are two “slope blocks” made of 4 curved slope bricks, and a supporting structure. One slope block is mounted on each side of the gun. The support structure is a mess of bricks with a stud on one side, headlight bricks, and plates. The top of the turret is plates on the front, and two sloped plate sections under each hatch. The two hatches are mounted to the turret support under the sloped plate sections. The AA machine gun is placed on the top, and various external mountings are placed in various ways around the turret.

T-55 Turret Detail

After making a lot of non-powered MOCs, it was nice to get back into Power Functions. I was pleased that everything worked flawlessly. The drive had adequate traction and power. The suspension worked well, and provided good floatation and travel. The turret rotation was smooth and allowed for precise directions changes. The gun elevation worked great, though I had to limit turret rotations to under four before the clutch on the mLA would snap. After a number of smaller builds, and frustratingly long builds, I was nice to finish something that worked well, provided constant entertainment throughout the build, and turned out quite nice.

Happy building.

Audi allroad


There are not many projects I start that I do not finish. I can count a couple. But, sometimes there are projects that take a long time to complete. I either loose motivation, lack parts (read budget), or find something else to do. If I were wise, I would toss the project, and move on to something better. But there is value to trudging through the slog and completing something difficult. The Spitfire is a great example of this. The Audi Allroad has been on The Queue for about 16 months, and it’s finally done.

The full gallery may be seen on Brickshelf or on Flickr.

Audi allroad

After completing the OCTAN F1, I thought I could use the suspension for an all-wheel drive car. I was sure I could make the front suspension with steering work at this scale.

allroad Suspension

I wanted it to have another fun feature, so using a bunch of differentials, I developed a simple three speed transmission. Three power functions motors are connected via two differentials which connect to the drive axles. Each differential acts as a subtractor between each motor. When one motor is running, the power moves through two differentials, and the car moves slowly. When two motors are running, the power moves through one differential, and it’s a little faster, and when all three motors are running the car is running the fastest as no differentials are splitting the power. I got it to work, and within a day, I had a working chassis.

allroad Driveline

Once this was done, the MOC sat on my desk for a long time. This past fall, Thirdwiggville welcomed another citizen to the village, and this gave me lots of time late at night to get back to working on this project. I spent a couple of weeks working on the body work with the perspective of “finish this.” So the body work could use a little more polishing; doors, mirrors, better lines, maybe an interior. But I was happy to finally get this done.

The MOC worked well. The suspension functions quite well at this scale, and the transmission was simple and effective. It could be a little quicker, but I was not going to make a substantial gearing change after the MOC was built.

Two final thoughts. I need to stop building supercars because they take a lot of time and effort for me, and I find little motivation for the body work; I do not think the body work looks good, and I lack motivation to work on it. Second, I needed to test the driveline earlier in the build process. I spend too much time fiddling with gear ratios after everything was build. But this project is done, and I am happy it is.

Happy building.

Kenworth T47


The Kenworth T55 is my favorite Trial Truck I have built. It’s not the best looking, or the most capable, or the most reliable, or even the most popular but it’s the one I keep coming back to. My latest truck is a continuation of the Kenworth series of trial trucks. The T55 would pull a stump, the T47 is quicker, has better steering, and more compliant suspension.

T47

Right from the beginning I knew the truck would have a similar cabin at the T55. It would continue with the four wheel steering, and I added an independent suspension. The dimensions would stay close to the same. From there anything else was fair game. I started with the axles. The new suspensions arms made it a little bit easier to make a good independent design. A CV joint was used at the steering knuckle, which allowed for the steering pivot to be near the wheel. Each wheel had about three studs of travel.

The XL motor was placed on the left of the center line and the rechargeable battery box was placed on the right. A newly acquired Servo Motor was placed rear on the centerline directly in front of the rear axle. I had a little more space left, so I added a simple two speed gearbox. A little more space remained so I added a flat six engine.

T47 Engine

Part of my attraction of the T55 has been it’s coloring, and it’s shape. I wanted to keep the attraction similar, but in a way that would differentiate the trucks. I have been acquiring some green lately, so I thought would be a great color. The cab is basically the same, but now it can tilt so you can work on the engine.

The off road performance was not great on the T55, and the T47 was similar. The independent suspension had too much play at the wheels to be great at steering, and the articulation was not very supple. The truck was great to drive around my house, but when I took it outside it did poorly. The suspension design is better than my last independent set up. There was no slipping of the gears. I think my next design will use the same knuckle, but design a different steering connection. This truck again proves the use of knob wheels rather than a differential for a trial truck. Feel free to make your own, and let me know what improvements you developed.

Happy Building.

Iveco XTR


After a couple of more complex projects it is nice to take a break to do two simpler projects. When I need a little bit of a design rest, I do a trial truck, and usually a fictional one, so I can build as I please.

The full gallery can be found here, and free instructions can be found here.

Iveco XTR

After building a number of trial trucks, I have found some features I like to have on my trucks. Note, these features may be prioritized differently if I was participating in a Truck Trial race. These features I like are linked suspension, PF XL motor for drive, tall clearance, and a center mounted battery box. As I was making this truck for my own pleasure, I forced myself to include all of these features.

I usually start a truck with the axles, and the Iveco was no different. I created the axle with a portal axle build around my favorite piece for both the front and the rear. I also added the space to fit both a differential, or knob wheels for the final drive (though the pictures only show the latter). This would allow me to switch the traction of the truck, and allow for a minor gearing change. While the changeover takes a little bit of time, it’s a nice feature and the gives the truck some versatility. I placed the steering motor directly on the front axle with allowed the middle of the truck to be simplified vastly. In the center of the truck is the battery box mounted longitudinally, and a Power Functions XL motor in the rear. This keeps the heaviest components of the truck in the center and low.

The linked suspension is a setup developed by other that connect two pendualar axles together. Each left side has a linkage that connects the two left wheels together, and the right wheels have the same. This keeps the wheels planted as the pressure from the terrain is balanced across all four wheels. When one wheel has to go up to follow the terrain, the rest of the wheels adjust. It is simple, effective, and keeps the truck a little more planted than a suspension utilizing shock absorbers. Otherwise the truck bounces a little during an obstical.

As you can see in the video, the battery box is getting a little tired, and the snow as a little mushy, but the setup worked well. The truck stayed planted, and it was nice to have two final axle options. It is a simple design that does not require too many hard to find parts, so if you need a good little afternoon project, give the Iveco XTR a build, and tell me what you think.

OK, off to some more complicated builds. Check The Queue. There is some fun stuff coming. Until then, happy building.

T-72 Instructions


It’s going to be a busy week in thirdwiggville. Before everything goes live, I thought it would be fun to let everyone know I have completed instructions for my T-72. I don’t know what took me so long. If you want to make a copy for yourself, you can for $5.   Buy Now Button

T-72

Otherwise, stay tuned.

Bedford MWD


I have said it before, but my favorite things to build are Trial Trucks.  The combination of the driveline construction, forces on the truck, diversity of body style, and various propulsion systems offered by LEGO combine for a great building experience.  Because of this, I usually am building a Trial Truck, or have one built at all times.  But for some reason, this truck seemed to sit for a long time unfinished.  I struggle with deciding if a truck will be a model of something, or something fictional.  This decision is often made too late in the construction process.  After toying with a Daimler Scout body, I decided I needed to finish this project and the Bedford MWD body was chosen.

The full gallery may be seen here.

01

After some some experience with various designs, I decided to construct a truck around a simple locking differential idea I had recently designed.  Because I would need an extra IR Receiver for the locking function, I decided a simple two speed gearbox (1:6 and 1:10) could use the other IR channel.  I placed all the controls in the middle of the chassis.  The driveline and the steering axle would run through the middle.  On the left side was the Battery Box and the motor for the gear change, and on the right side was the XL drive motor, the gear box, and the motor for the locking differential mechanism.  The steering motor would hang out the back of the chassis over the rear pendular suspension unit.  Both axle were connected by my favorite linked suspension system.

zbedford

Each axle took a little bit of work.  I selected a simple design for the locking differential.  Basically, it is a 24 tooth differential placed directly next to a 24 tooth gear.  A pair of sliding 12 tooth double bevel gears slide back and forth one stud to connect only with the differential, or with both the differential and the neighboring gear locking out the differential.  After toying with some old flex cable, and some pneumatics, I figured I was making it too complicated.  I added a small pivot with a Small Technic Steering Arm, and connected it to a 9L link.  This way both axles could be connected, the suspension and lock could keep operating unaffected by each other, and it all could be controlled by a mini Linear Actuator.

Initial tests were positive, so I then decided to figure out a body for the design.  I worked for too long on a Daimler Scout body.  I had the structure made, but the paneling was just not happening.  After sitting on the project for 5 months, I decided it was time to make something new.  The Bedford design worked well, and helped my get excited again in the project.

Now, once I got outside to drive the truck a glaring problem occurred.  The bevel connection in each axle that transmits the longitudinal drive forces to transversal drive forces kept slipping.  You can hear it in the video.  Because of this, it did not matter if it had locking differentials, or if it had a two speed gearbox, or if it had working suspension.  Anything could stop it.  I though about reworking the axles, but then, I have been working on this for 11 months, it was time to be done.  I’ll use the locking mechanism again.  That worked great.

Thanks for reading.

CAT 573C Feller


LEGO takes up space.  We all know this, and yet we still seem to try to cram as many working functions into a MOC as we can.  Sometimes it works out well.  Sometimes we have to scrap a few functions.  Other times, the functions are so dense you really cannot believe you got it to work.  This is the story of my wheeled feller.

The full Gallery may be found here. Instructions may be purchased for $5 USD.  Buy Now Button

CAT 573c Feller

I have been thinking about making a feller for about two years now.  It is a project I have never seen done before, with the exception of two tracked fellers (OK, and my other one).  Over this time, I have been planning, acquiring parts, and making plans, and over the last four months I have been building.  Nothing I have made has been so complicated or so dense.  There is no space left.

As I always do, I stared with the dimensions of the vehicle.  The schematics for the CAT 573C were easily available, so I stared with the chassis.  I knew space would be an issues, so the driveline had to be simple and compact.  The Power Functions XL motor would be geared down 3:1 and mounted just behind the rear axle.  A drive shaft would move through the steering pivot to the front axle.  The rear axle would have simple pendular suspension.  The steering would be completed by two linear actuators placed on either side of the pivot with a PF M motor on top.  Simple enough.

From here, things got complicated quickly.  The MOC would have four remaining functions.  The feller saw, the grapple arms, the feller tilt, and the feller lift.  Since trees are rather heavy, fellers are designed with as many of the system mechanics behind the rear axle.  As such, all of the functions I would add would need to be in the rear, as the front would not have any space.  I quickly learned this would not work.

Eventually, I found what would fit.  The IR Receivers would make up the rear bumper, and the battery box would be directly over them, off to the left.  Two PF Ms would be on the right and would drive two mini Linear Actuators.  These would move two pneumatic valves. These pneumatics would move the lift function and the grapple arms function.  An air tank would supply the pressure from a pneumatic pump placed on the driveline.  Another PF M would be placed over the front axle to give the feller head the tilt functions (it should be noted, 7 designs, and five weeks were spent on this feature alone).  The final PF M was in the feller head, and would drive the feller saw.

After packing, repacking, and packing again, all the features we set.  Then all the cabling and hosing were placed.  No easy task, as I was running out of space, and 25 or so hoses, and 10 cables take up a lot of room.  I added some comfort features to the cable, including a (half) chair and a roll cage.  And so Mr. Technic could get in, a little step.  Then a lot of paneling for the rear, including some access doors on the rear, and the model was done.  Here it is in action.

As you can see in the video, the MOC worked well, but some of the functions did not work as clean as I would have liked.  The drive and steering were fine, with an easy drivability.  There was a lot of mass in the back, so sometimes the torque from the drive motor would cause the back to tip.  The saw worked well enough, and for the most part so did the tilt, but the pneumatic lift struggled.  It was a little overloaded because the saw unit was too heavy.  The grapple arm worked well, but for both pneumatic rams were hard to control.  As always with LEGO pneumatics, they too often are off or on.

Until the next MOC, happy building.

Talon Track


Every once and a while I see something so creative I have to build something like it.  I happened with my HH-65.  It happened with my Zil 132.  And to some extent it happened with my Spitfire.  But when I saw the Urban Buggy from Chrismo, I though I have to make something like it.  It was such a fresh and creative design.  It had such great lines, a perfect stance, and a unique driveline setup.  But while imitation and outright plagiarism are the most sincere forms of flattery, I thought something of my own design would be a better contribution to the LEGO community.  I present my Talon Track Car.

You may find the full gallery here, and the instructions here.

I designed this car to be fast and stable, just like a track car.  I started with a drivetrain that would be reliable and effective.  A PF XL for drive, and a PF M for the steering.  I placed the PF M in the front mounted directly on the suspension unit, with a return to center spring in the middle of the mount.  The system is set up differently than in my Rumble Bee, but uses the same return part.  Each suspension arm would have a single shock absorber.  Directly behind the steering motor was the XL for the drive.  It was geared up with a 20z/12z ratio, with the driveshaft connecting directly to the 20z gear that turned the differential.  The rear suspension used an independent setup that was developed a long time ago for my Red Car Bigger (great name, huh).  If it’s not broke, don’t fix it.  The suspension was planted.  I placed the rechargeable battery box and the IR receiver behind the rear axle.

The car was quick, and didn’t have any problems, but faster would have been cool.  The return to center system worked well, especially for the quickness of the car, and the quickness of the steering.  It was easy to control.  The car was robust, and crashed well.  So go ahead and build your own.  Enjoy.