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 at 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.

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Forest Fire Truck


Everyone once and a while I see a design I like so much, I copy it. So thanks to Horcik Designs on the fun little Fire Truck that I copied. Thanks for the inspiration.

The full gallery may be found on Flickr and Brickshelf.

When I found Horcik’s fun little Fire Truck, I was immediately enamored with the look of the truck. After deciding I was going to make it, I started looking for additional features to add to the excellent design. After finding some great ideas of a Renault version (2), I decided to get to work. The truck started with a 4×4 driveline and an I-4 engine. I used a simple live axle setup with 9l steering links to keep the sway movement in check, and both axles used a Panhard link. The steering was actuated with another 9l steering link, rather than the more common rack and pinion setup. This allowed for a lower engine mount, and something a little different in the design. The steering can be moved by both lights on the roof of the cab.

Which brings us to the cab. I wanted to use the face of Horcik’s truck, but wanted to add some changes. I added two doors to make the cab a little longer, and added four of the new panel parts that work great as seats. Then I made sure the cab could be tilted simply, and connected the two roof lights to the steering. You can see the engine and the steering when the cab is tilted.

Then off to the body. It turned out to be more simple than I had planned. I had some ideas for a hose reel, a roof mounted water gun, and various cabinets with tools inside. Every idea I tried was a little ugly, or boring. So, I closed up the design with a couple of water tanks inside the body of panels. It’s not fancy, but the design turned out clean, which is what attracted me to the project in the first place.

The design worked fine, though the front axle could be a little more robust. It was not a complicated build, but it was a fun one. Don’t worry, there will be complicated builds coming soon.

Happy Building.

Power Functions 4×4 8081


For most LEGO enthusists, when they purchased the set 8081, they quickly modified the set with a Power Functions drivetrain.  It makes sense.  LEGO models are a little more exciting when they are motorized.  But I guess I went a little backwards.  I wanted to do the fun stuff first, and make the most complicated and compact drivetrain I could make.  I posted the instructions here, and they can also be viewed on Rebrickable.com.

But the comments kept coming from people who wanted to see my model motorized.  So I thought it might be a fun addition.  I added a two PF M motors, a 8878 Battary Box, and an IR receiver.  I tried to keep the modifications simple, so I could easily add the motors to the MOD, and take the system out if I wanted to.  The drive motor was placed on a simple mount that connected to the frame.  The power was fed thought a 8z gear to a 24z gear which then connected directly to the V8 driveshaft.  The driveline was unchanged from the V8 down.  The steering motor was mounted laterally in front of the rear seats.  A 20z double bevel gear drove a 16z gear, then a worm gear moved the final 8z gear which was mounted on the existing HOG steering axle.  I removed the passanger seat which is where I placed the battary box, and created a simple mount for the IR receiver.  The added weight required a new shock absorber, so I added that as well.

The model worked alright.  The drivetrain did well to handle the new power, and I could easily control the Crusier.  The steering motor was a little too powerful for the upside down facing steering rack.  It skipped a little under load, which was a problem over rougher terrain.  The drive motor was a little taxed, so a PF XL would have done a little better.  I guess I could add that, but I am ready to move on to my next model.  Stay tuned.

The full gallery may be found here.

4×4 8081


Truthfully, I was excited about set 8081 when it was first announced.  I liked the size.  I liked the coloring. I liked the stance.  But mostly I liked the potential.  Most of the Technic community dismissed the 8081 because of its watered down functions, but I was interested in making some changes to see if I could make the Cruiser Extreme.

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

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I first added a V-8.  There was plenty of room, and after seeing a great modification from Efferman, I had some ideas.  It was a simple addition.

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Next was the drivetrain.  This was a little more complicated.  I wanted to make it four wheel drive, and I wanted to make sure there were three differentials.  I rebuilt the rear axle, so It would have a more active setup.  I put in longer shocks, and added a Panhard rod, and two stabilizing links.  It worked well.  The front axle was more challenging.  The new CV joints made the project a little easier.  Once I had the differential place, I had to fit everything around it.  The steering rack was placed upside down, and was connected directly to the existing steering link in the original 8081.  Then I added a Panhard rod on the front of the axle, and rebuild the front bumper, and everything was set.

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Instructions can be found at Rebrickable.com or here.

Full gallery is here.

I also created a motorized version after a number of requests.  You may see the gallery for that MOD here.