Polls!
Should 3D printing be allowed in some way?
- Yes
- No
0
voters
Do you have a 3D printer?
- Yes
- No
- I would get one if vex made it legal
0
voters
Should teams have to release 3D printed designs?
- Yes
- No
0
voters
2 Likes
A lot of this discussion is about the 3d print file/code/notebook sharing. As someone who [bias] has a pretty good notebook and codebase [/bias], Iād be happy to share the contents of either.
In my opinion, if you canāt win while sharing, you donāt deserve to win.
Just as an example, in its lifespan, team 9935E has won one judged award. Notebook sharing could be a way for your team to improve by learning from other teams. It seems pretty reasonable to try, even if youāre not confident in your own notebook.
11 Likes
when teams make their code so plug and play people can just directly copy and use it
1 Like
Having reviewed many teamsā code over the years, this is not a thing.
6 Likes
Further, having review many teamsā code over the years, I canāt think of any that would even be close to being plug-an-play. Substantially, teamsā code is:
- Highly specific to a single robot
- Poorly commented
- Difficult for an outsider to understand
11 Likes
Iām not going to bring my bot to events so nobody steals it. 
13 Likes
Lets try this to see how united the front is around not publishing.
- Our team would print parts and publish them
- If required by the rules to publish then my team would not print parts
- Not going to print parts, so our team doesnāt care
0
voters
Personally, I do this so I can easily change encode between robots and have all of my base functions there. I have been using the same program more or less since tower takeover.
2 Likes
I think we all understand that the first and most important part of VEX and VRC is to learn, and to get people engaged in STEM, and that should be the main focus, hence the push for the rule of making 3D parts public.
However, at the same time, VRC is a competition, hence why some are probably hesitant to make things readily available for anyone to look at and use. I think that making everything (parts, notebook, and code, whatever else) available at the end of the season is beyond fine, but I can understand some being hesitant releasing everything they have mid-season.
5 Likes
I think some of you guys are assuming that printed pieces arenāt going to be modified after being printed. Drilling and cutting donāt add any material and thus wouldnt cause much of an issue, but by using things like using a 3D printing pen (which would most likely end up being legal if 3D printers are), you can weld prints together, or add smaller custom structures onto the prints. Additionally, itās possible (although difficult) to completely create functional parts just using a 3D printing pen.
I can see the benefits of having a public repository of files for new students to learn from, but making it mandatory sounds as ridiculous as forcing teams to upload files of their polycarb pieces.
13 Likes
Iām pretty familiar with 3D printing, I noted a few posts above that people are embedding metal inserts for screws or maybe embedding an axle support. I understand printing is just a part of the process.
Iām after a way to get this to fly with a number of groups. While the expense of a 3D printer problem has been somewhat removed, the next thing will be the complexity of using CAD to make the parts. So access to a set of parts will get past that hurdle.
From the two polls people are slightly in favor of having the designs available. When the push comes to publish over 80% would print and publish. You can decide that you donāt want to follow that and not print.
Iām super excited that many of you have the design for the printed part that will give you the lock on winning this years Worlds. It will be a nice change from last years Worlds where there were basically two designs and the winners were decided by strategy and driving skill.
I donāt want to bog down into a morass of legal (can I use a 3D pen can we take multiple small parts and make a bigger part, can we drill holes, cut the printed part in half, can I just melt plastic in a microwave and hand form it. etc.) 100% of the roboteers want 3D parts, Iām trying to make that happen.
5 Likes
My hesitancy with the 3D printing is that it creates a disadvantage to teams without access to the feature - nothing new to this discussion.
My suggestion would be to have a maker section in the Vex inventory. Letās say a team designs a custom part. If they check it into Vex then it becomes a āVex partā which would be legal for use in a competition. Other teams could have that part produced at any one of the many 3D printing shops. No one team gets the competitive advantage.
There are loopholes and Iām sure there would need to be an approval process but it helps maintain that balance.
It sure this could be expanded into an online competition with credit to the engineer that made it. If the part has demand then Vex could fold it into their product line.
3 Likes
I got the suggest that there is at least a āblue boxā note in the manual that 3D printed high-stress parts, like sprockets and gears (printed with any consumer-level printer) will likely disintegrate in competition because there is no comparison of strength and toughness with injection molded parts.
I agree, there would be nothing worse than building a custom part have it work in the shop and have it explode when put to the test in a match.
I also got a note that 8/32 threaded inserts
would also need to be allowed. Iāll submit a Q&A question, they may fall under the lines of fasteners, they are just really weird 8/32 nuts.
2 Likes
You might be surprised; VEX U teams have used 3D printed gears and sprockets in the past without issue (and usually out of common materials like PETG). Sure a note wouldnāt hurt, but 3D printed parts can be quite strong as long as you print them in the right orientation (which luckily is the natural orientation to print parts like sprockets and gears).
7 Likes
This is just factually incorrect. If designed correctly 3d-printed gears can match or even beat the strength of stock vex gears. Iāve used a 3d printed gear as the slip gear in a catapult and the stock vex gear it was mating with broke before the 3d printed gear.
Yes, there have been studies that shown the mechanical properties of a 3d printed part can be 25-50% weaker than an identical injection molded part of the same material, however stress is inversely proportional to cross sectional area. Doubling the thickness of a part halves the stress and thus increases the strength. By correctly designing the part you can overcome the loss in strength from 3d printing.
I think 3d-printing would be a good introduction to teams in learning the strength of materials and how to optimize design for strength.
15 Likes
@Andrew_Strauss and @demonicyoshi Thanks for that. Do you want to suggest wording for the blue box that would help or just let it go?
1 Like
I would say either omit the box or just put in it that teams are responsible for ensuring that their parts are designed to reduce failure.
Maybe vex could add a resource for teams explaining basic material properties and stress/strain. Kind of like how they do for explaining how the motors and sensors work
7 Likes
So let me see if I have this clear in my mind, cause this seems strange to me. If I were to cad out a piece, 3D print it, and use it on my robot I would have to share that cad file on a public thread or file accessible to anyone? Would you be able to choose to use 3D printed parts and not share?
If you are a VRC competitor yes. You will finally after years and years of asking be able to do 3D prints! Publishing them helps jumpstart other teams that donāt have your design skills.
You need to share to be able to use them. If you download a part and donāt change the design, you would still need to reference the original part. The part doesnāt not need to compete, you can become a designer and design cool and useful parts and publish them for others to use.
1 Like
This aged slightly poorly.
That first poll is now showing a little under 2/3rds of people would rather not share midseason if they donāt have to, which makes sense, since VRC is still a competition. Yes, 82% would print & share if push came to shove, but itās apparent itās not most peopleās first choice.
Is there really anything explicitly wrong with releasing at the end of the season? I get that newer teams might struggle more because they have less experience, so thatās a downside, but other than that?
I also thought about a potential loophole: Whatās stopping a team from posting for competition inspection, and taking it down the next day (or later that day even)? I donāt really see that one being easily enforceableā¦
6 Likes