Frequently Asked Questions

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Wait. Wasn’t this previously called The Philadelphia Rube Goldberg Machine Contest?
Correct! We launched in 2015 as The Philadelphia Rube Goldberg Machine Contest, and it was an amazing event that was part of Rube Goldberg Inc., the company that sanctions the Rube Goldberg Machine Contests around the country. Unfortunately, Rube Goldberg Inc. dramatically increased their registration fees for each team. So, we decided to relaunch as The Philly Contraption Contest to make it possible for everyone to participate.

So there are no Rube Goldberg machines?
Oh, there will be plenty of Rube Goldberg machines. We just can’t call it a “Rube Goldberg Machine Contest” for legal reasons. It’s largely the same competition that attracted several hundred people and news cameras in 2015. It just has a new name.

So what the heck is a Rube Goldberg machine?
A Rube Goldberg machine is a contraption that is deliberately engineered to accomplish a simple task in the most complicated and absurd way possible through a series of steps. The more — and the more ridiculous — steps, the better. The machines are named after the American cartoonist Rube Goldberg.

Oh, like the game Mousetrap?
Yes, that classic board game is based on a Rube Goldberg machine for a mousetrap. Visit our Videos page to see more examples of Rube Goldberg machines in action.

What’s with the registration fee?
We used to steer clear of registration fees. The problem was that we’d have teams register for free and then drop out at the last minute or just not show up. So in order to get more of a commitment out of each team, we are requiring a $250 registration fee per team. This fee will be fully refunded after participation in the event, and it will not be refunded to any team that drops out after registration. In other words, it’s free to participate, and it’s not free if you drop out.

What is a step?
When energy is transferred between two different actions, that is a step. For example, when a wind-up car with a pin on the front of it collides with a balloon, popping the balloon, that is a step. But if you line up 100 dominoes and push one, making them all fall over, eventually knocking into a ball that’s sent rolling along the floor, that is one step. Not 101 steps, because there are only two different actions.

So the task is play a musical instrument? Which musical instrument?
Any musical instrument whatsoever that you can get into the venue and that fits inside the space allotted, from a timpani to a banjo to a kazoo to a trombone to a Moog synthesizer.

Are you providing us with musical instruments?

By “play a musical instrument,” do you mean play a note, play a song, play a chord?
Any of those would work.

So we could literally just have a stick hit a triangle in the end? Or a bow move across a violin string? Or a basketball bounce off of a timpani?
Right-o! Now you’re getting the idea.

If we used a synthesizer, could we just have something hit a key on a keyboard that then triggers a whole digitally-recorded song?
Sure, you could do that. But do you think the judges will be more impressed by that or by a machine that manages to play a trombone or strum a guitar chord?

What if our machines plays more than one instrument?
Now you’re talking! That would be ridiculously fun.

What happens if my machine gets stuck? Can someone on my team intervene?
Yes. This happens more often than not. Let’s say that the wind-up car with the pin on the front of it goes off course and does not pop the balloon. Someone on your team can step in and pop the balloon. But — and this is a big but — your team will lose points each time this happens.

What happens if we don’t finish our machine in time for the contest?
That is an excellent question. Building a Rube Goldberg machine is no easy task. It requires dedication, commitment, perseverance, hard work and a lot of other things. Last time we threw a Rube Goldberg machine contest, we had a significant number of teams register and then pull out at the last minute. It was a REAL bummer. You should know that by registering, you are taking up a slot that could be used by another group of children, as the space is very limited. If you’re going to register, please come up with a schedule for building and testing and stick to it.

Also, keep this in mind: Your machine doesn’t have to complete the task in order to participate. It’s not about completing the task so much as it is about trying to do so in the most absurd and complicated way possible. We have had teams with incomplete machines show up and have fun.

Can I just let my mom or teacher build the machine?
We encourage you to have adult assistance throughout the process, but having an adult do all the work for you is unfair and uncool. And we’re pretty sure that your mom or your teacher wouldn’t do this for you anyway, because they know the value of hard work. You will need a parent or teacher advisor with you at the competition, but they are not allowed to be involved in the oral presentation or the running or resetting of the machine. One — and only one — adult can assist with setting up your machine.

What if we have some middle school kids and one of their brothers, who is in high school, wants to be on the team?
That’s fine, but if you have any high school students on your team, then you need to follow the high school rules, which means a minimum of 20 steps for your machine.

Why do we have to do an oral presentation?
The best machines tell a story, and an oral presentation is part of the storytelling process. You should definitely find the loudest, funniest kid to deliver the oral presentation. You’ll be judged on it. In the oral presentation, you will also explain to the judges the steps of your machine.

How much does it cost to build a Rube Goldberg machine?
It can cost virtually nothing. The best Rube Goldberg machines utilize common household objects and recycled materials. You’ll likely also use levers, pulleys, tubes, ramps and balls, among other things.

But certainly it will cost something. Where are we supposed to get that money?
We recognize that some schools and organizations have funds for awesome projects like this while others do not. If you need to raise money, try a bake sale, car wash, chili-cooking competition, etc. Or, you could try crowdfunding on the Internet via sites like Kickstarter, GoFundMe, HatchFund or IndieGogo.

Are there prizes?
You bet! Trophies and other awards will be given out on the day of the event.

Does the task in question have to be the final step?
No, but for judging purposes, we don’t count any steps that occur after the task has been completed.

Is the completion of the task counted as a step?

Can I use a remote control or cell phone or something like that to start the machine?
Yes. A remote control can be triggered by one of the team members to start the machine. For instance, maybe the person giving the oral presentation gets a phone call during it, and the act of picking up the call triggers the first step in some funny way.

Can a remote control device be used elsewhere in the machine?
Well, sort of. A remote control device can be used elsewhere in the machine but only if the transmitter and the receiver are both contained within the footprint of the machine and not controlled by a human. In other words, step 18 cannot be triggered by a teammate pressing a button on a remote control, but if a ball rolls down a track and presses a button on a remote control that then triggers another device, that’s perfectly legit.

Can dry ice be used?
Yes, as long as safety precautions are taken.

How many teammates can touch the machine during its run?
You can’t have more than two team members touching the machine simultaneously during the run. As for the entire duration of the run, there is no limit on how many teammates can touch it throughout the run, but keep in mind that for every touch, points are deducted. Once a teammate starts the machine, it will ideally run without any intervention.

I read that fire and explosions are not allowed. What about an “explosion” caused by baking soda and vinegar or Mentos and Coke?
We’re talking about dangerous explosions. The Mentos and Coke trick is always a big crowd pleaser. Just be prepared to mop up after yourselves.

If a team doesn’t use all of its 3 minutes of oral presentation time, can it have more time for its run?
No, the maximum run time is 2 minutes.

How many teams can enter from the same school or organization?
One in each division, so a K-12 school could enter a middle school team and a high school team, and each would pay the registration fee.

Can a machine include a 10 megawatt laser? What about an electromagnetic pulse bomb?
Nope. All machines must be safe for the participants, judges, spectators and facilities. Any machine deemed unsafe by officials will be disqualified.

I heard that we’ll be judged on things like “absurdity” and “humor.” Can’t I just submit a serious machine that’s not absurd that that doesn’t make anyone laugh?
Sure you can. Just keep in mind that you will be judged on absurdity and humor, and a really absurd, really funny machine that doesn’t complete the final task could actually beat a boring, serious machine that does complete the final task. Get into the spirit!

Will the judges surround the machine completely?
No. Judges will view the machine from the front of the machine, either in a seated or standing position. Keep this in mind when designing your machines. You’ll want the judges to easily see all of the steps, especially the final one. We understand that there are a lot of small, intricate movements in most of these machines, and that’s fine, but you should have as many big, showy movements as possible.

How are we supposed to get the machine to the contest?
Depending on the size of your machine, this can be challenging. Many teams elect to build larger machines in smaller pieces that then fit together easily at the venue. In any event, you will need to think about transport, whether it is in the bed of a pickup truck, the back of a minivan, or in a U-haul truck.

Will you provide a table for our machine?
No, you will need to bring whatever table, platform, etc. that you need to display your machine.

Why can’t we just do the judging run and be done with it?
Because we want as many people as possible to see your fantastic machine. We expect a large number of spectators. All teams are expected to run their machines for the spectators throughout the day. There are going to be a lot of people there excited to see what you’ve created.

My Girls Scout troop wants to send a team to compete. Can we do that?
Yes. Teams are also welcome from homeschooling groups, robotics and science clubs, neighborhood community centers, church youth groups, etc.

2 thoughts on “Frequently Asked Questions

    1. One person can do it, and that’s usually what happens. Once in a while, you’ll see two people doing it in tandem, but only when that makes sense for the story and presentation. In general, pick your best, most dramatic, and loudest speaker and give that task to that person.


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