Today’s guest article comes from Bethany Wright, a builder, LEGO educator and Tips&Bricks contributor who makes MOCs move and runs Interactive Bricks.
Making MOCs for a LEGO Convention
“But could you make it move?” I remember looking skeptically at my friend, who had just challenged me to try something with LEGO movement. I knew nothing about gears. I’m not an engineer. But here he was, daring me to try something new.
I had seen plenty of builds with complex movements. I even found some free instructions that helped me go from zero knowledge to understanding basic movements. But when it came to incorporating that movement into MOCs that I displayed at LEGO shows, I was woefully unprepared for what I was about to encounter. I’ll spare you the details of what went wrong at my first show. Instead, let me share the lessons of everything I learned the hard way…
Starting from the Ground Up
They say the key to any success is a strong foundation. And when it comes to your LEGO builds, the same thing applies. I begin all of my builds on a modified MILs structure. I say modified, because I do mine a little differently. The typical MILs structure uses a baseplate, brick, and plate to create a sandwich. Typically, the bricks are spread out every few studs.
When it comes to MOCs with movement, you want the sturdiest base you can get. If you pick up your build and the plate begins to buckle, it could mess up your mechanics. So I cover every single interior stud with bricks. It’s a great way to use up FLEGO (fake LEGO), damaged bricks, or other unwanted colors.
Example of my Modified MILs Plate
This also allows me to pick up a heavy build in one hand with zero concerns of buckling. (Although be smart. Always use two hands. Why tempt fate?)
Know Your Tools
I don’t know if this is the result of getting older – or maybe my memory just fades faster than a white LEGO brick in the sun – but I find myself needing to keep examples around. I keep a bucket of movement models handy so that when inspiration strikes, I can refer to a variety of ideas.
My Bucket of Movement
I also keep reference books on hand for ideas. My favorite is Simple Machines by Yoshihito Isogawa, although you can’t go wrong with any of his books.
Draft Your Movement
I like to begin planning my movement with a rough draft. Often I’ll take a few mechanisms and sit them on my baseplate. This allows me to brainstorm connecting one movement into another, but also helps me make sure everything has its own space.
Drafting my movements and laying out the build
Work in progress: Chariot + Wolf + Windmill
I usually begin a build with one idea (let’s call it my focal point). In this case, my focal point was rabbits pulling a chariot. I saw that I had space for a sliding mechanism to represent a character running away from the chariot, but not space for the original mechanism I had in mind.
Drafting allows me to see how new elements work with my focal point and fit into the story I want to tell. I’ll add one element at a time, which allows me the freedom to remove something if it doesn’t fit mechanically or conceptually.
Test Early, Test Often
If you’ve watched any episodes of LEGO Masters with movement, you’ll hear the judges warn: “make sure you test it.” I test run every component of a build, making sure it runs smoothly for at least a half hour each time.
Before Piglet Went Crazy
For my very first show, I had no idea what to expect about running my build. I thought, “Oh, I’ll just turn on my build when someone walks up to my table.” I didn’t realize how frequently people would walk by. I almost never had a chance to turn it off!
One of my mechanisms used a rubber band as a belt to help perfectly pivot Piglet playing Pooh Sticks on a bridge. It worked great in tiny spurts. But by Day 1 the rubber band had stretched out and Piglet unevenly whipped back and forth.
I learned not just to test, but to let things run on an extended timetable to troubleshoot for problems.
Allow for Repair
Windmill wall pops off to access bevel gears
If there’s one guarantee in LEGO mechanisms, it’s that it’s not if but when things will break. We’re dealing with plastic toys, not precision instruments. Just ask any Great Ball Contraption builder: things will need to be repaired.
Therefore, I build with repairs in mind. I like to call it Strategic Hiding. Walls remove, boulders pop off. The goal is to have easy access to your mechanism so you can fix it. I use jumpers to help things come apart easily. I also build false walls, removable panels, and other tricks of the eye. It becomes a fun puzzle!
Rock pops off – notice the jumpers and hidden motor?
The top removes in sections, popping off the jumpers
Take Pictures of Your Mechanisms
It’s inevitable when you travel that your builds will get jostled. Sometimes a bushing slips or an axle needs to be replaced. Take pictures of your mechanisms so that when you take everything apart to repair, you know how to put it all back!
Your pictures might not be pretty, but they’ll save you later!
Watch Out For Expensive Stuff
Dust around the base of my swirling alien tentacle
After running your builds for a few hours, you might notice white dust. The dust is actually LEGO disintegrating with friction. It doesn’t matter the color of the LEGO element, it grinds down to white dust.
Watch out for anything with stickers, prints, or other expensive elements. It’s hard to consider LEGO disposable, but it will get worn down. So make sure you are using parts that you’re okay replacing.
Create a Repair Kit
Speaking of things needing repaired, definitely create a repair kit! As a rule of thumb, I try to pack two of everything. If I used one 8 tooth gear in a build, I’ll pack two. This gives me flexibility in case I need to repair or rework something on the fly.
My repair toolkit
I pack parts I find useful: bushes, pins, connectors, gears, liftarms, axles, belts, pulleys, cams, etc. But I also pack tools like brushes to remove any white dust and tweezers to help pick up tiny parts that might fall into the build.
No sound is worse than the tinkle tinkle of dropped parts
Lubricate Moving Parts
I learned from Train builders that train wheels need to be lubricated to maintain their smooth rolling. I’m very grateful to the AFOL who showed me how to use Tri-Flow to lubricate LEGO axles. I put them inside Technic bricks, and between the gear and brick. NEVER lubricate between gear teeth.
Tri-Flow to the rescue!
Mark Bumpis taught me to use Vaseline where LEGO slides on LEGO. I use a Q-tip to help things glide across tiles. Petroleum jelly does not degrade or eat away the LEGO plastic. I’ve seen people use other materials to lubricate their builds, but be aware that some lubricants can cause build ups on the material and some might dissolve the LEGO.
Vaseline and a Q-tip is my secret weapon
If you see your mechanism start to stutter or if you hear a high-pitched squeak, a touch of lubrication will go a long way to helping the longevity of your build.
Ready, Set, Go!
I’ve learned other tricks of the trade over the years, but I’ll save those for another time. Hopefully you’ve been able to learn from some of my mistakes and you can be successful in your quest to bring movement to your MOCs.
If you’re not sure how to get started with movement, I have free instructions on my website. I also have details about where to find motors and how to power your builds. I also have a series on Tips&Bricks called Making Mechanisms Move that highlights different applications of mechanisms.
And if you have any questions, hit me up on Instagram and I’m happy to brainstorm, troubleshoot, or help however I can. I also started a Discord for creative movements – a place to search for mechanisms and get advice. If you want to join, shoot me an email or DM. Happy building!
What’s the most challenging problem you’ve had to solve when displaying a motorized MOC at a LEGO event? Let us know in the comments below!
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