When is paint considered functional?

At a recent event I saw a robot that had been painted, and it looked awesome. However, the painting was done after the robot had been assembled, and had been laid on very thick, thereby cementing any fastener on the robot in place. Does the paint then become functional, since it has essentially glued to robot together?

No, it’s become an annoyance to the builders because there is no way to take it apart and make any changes to it.

Post pictures, we all love a greatly decorated robot.


Instead of paint, you are legally allowed to use loctite to hold screws in place. If you had other functionality in mind like physically holding pieces together, paint isn’t strong enough to do so and screws are much easier to maintain and modify anyway.

I wouldn’t recommend painting a robot after assembly, as paint can cause unwanted friction and is illegal/functional when applied in instances where the coefficient of friction of parts of the robot (for example lexan on a tray) advantageously change.

Paint, powder coating, anodizing, or other forms of decoration are amazing, and they really amplify the beautiful engineering of many teams, but these designs should generally be premeditated, so application can occur prior to robot assembly and issues of friction can be easily avoided.


Sorry, don’t have any.

The rules state you can use loctite. Not some other thing that might work like loctite. Paint could very well be a strong adhesive if it’s formulated and cured properly.

I’m not debating the extra wow factor paint as a decoration has, but in this case I feel like it was more than decoration. Literally 100% of the bot structure was covered, including fasteners. I just can’t say for sure if it provided any discernible advantage.

If you have issues with a particular team, contact your RECF RSM since it is after the event.

I’m just gonna go out on a limb and say if a team is “glueing” their robots together with paint, idc how perfectly cured it is, that team will not get very far. Vex is a dynamic process and it’s stupidly inefficient to iterate and prototype with glue instead of screws. If you are concerned about a team doing this feel free to report it, but I believe it would cause a far larger disadvantage than it would an advantage. Anything they can do with glue, you can do with screws.


Furthermore, even if the paint is as strong as you fear, it shouldn’t make a difference. On most good bots, screws and bolts rarely fall off. If anything, this purposeful “gluing” signifies an engineering deficiency, adds weight, but doesn’t make too much of a difference overall. Now, I’m not saying your are, but if you are hypothetically salty that they won and see this as a way of DQing them, that really just seems like a very bad move imo. That robot’s screws probably won’t come off readily, with or without the paint.


FYI, I’m a ref. I don’t care who wins, I just want them to do it fairly, according to the rules. I thought it was an interesting discussion about the how rules can be interpreted.

Clearly gluing a bot together with paint by itself won’t work. Using paint to keep fasteners together and the bot from loosening over time and/or modifying contact surfaces. In this instance the pain was thick enough the hex in the screw ends was nearly invisible. This will act like a thread lock keeping the screws tight.

Did it give them a competitive advantage? I don’t know. I just wanted to discuss it.


Paint may have additional stability results. For our tray, we have one segment that was painted after it was assembled and the L pieces on either side do in fact, not wiggle around nearly as much as the pieces that were painted before assembly. However, I believe that thread lock(even the blue kind) would have been much stronger than the paint we used and painting just for stability isn’t worth it.


Oh I understand where you are coming from now. Sorry I didn’t know you were a ref. In that case, I still don’t think it should be illegal because even if it is acting as a thread lock, thread locks are allowed. Furthermore, I would assume regular thread lockers are much stronger than paint. So in my opinion, I wouldn’t regard it as illegal, just adding excessive weight. I can see the functional decoration argument, but it’s functioning (if it is) extremely close to a thread locker. I would think instead of a competitive advantage, they would be experiencing a disadvantage due to the weight addition if it is as bad as I think it is based on your description. Another example would be nylocks. This is in the sense that nylocks are legal to use but almost never get loose or come off and aren’t any sort of secondary thread lock (as in loctite or paint but rather a component in assembly).

Also, If they painted the bot after its assembled, it isn’t likely that the pain got into the threads of the screws.
Besides, what is that team going to do? They cant really fix that at the event.

1 Like

If you can’t get your robot into compliance, you can’t compete. Simple as that.

as much as I would like to do that at an event, the guidance for EPs is figure out how to get teams to compete. It may be impossible.

I would recommend posting this question to the Q&A and get GDC to weigh in on this.


Question: When is a lot of paint considered TOO MUCH paint? At what point does it go from non-functional decoration to functional because it is so thick that it could lock the stuff together or could provide additional stability?

Here’s my tongue-in-cheek representation of what the official Q&A response would likely be (based on some previous Q&A answers):

at the Head Referee’s [INSPECTOR’S] discretion

We are not going to be able to provide a point-by-point checklist to determine where to draw this line. The answer to all of your specific questions is, “it could”.

Seriously, though, this is exactly the sort of thing (IMO) that they are talking about with those sorts of responses. If it COULD be considered functional by someone, then it COULD be considered by any inspector at any event to be functional and it could become an issue. That doesn’t mean that it WILL be considered functional, or even that if it is considered “possibly functional” they would immediately be forced to withdraw; it probably depends on the event. At a high-level event I would assume the possibility becomes higher (of both it being called out as functional and it being a big deal). Therefore, I personally would recommend that paint be limited to an amount that is unlikely to be considered functional by anyone…

Game Manual

R12 Decorations are allowed. Teams may add non-functional decorations, provided that they do not affect Robot performance in any significant way or affect the outcome of the Match. These decorations must be in the spirit of the competition. Inspectors will have final say in what is considered “non-functional”. Unless otherwise specified below, non-functional decorations are governed by all standard Robot rules.
a. Anodizing and painting of parts is considered a legal nonfunctional decoration.


What competition were they at?

I’m not going to call out any team here, I just wanted to have some discussion about the topic.

That being said, I’m sure the team in question has figured out who I’m talking about and if they’d like to post pictures more power to them.

I just competed with a painted robot at the Bellaire competition in Michigan. I was wondering if it was my team you were referring to.

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.