improving build quality

hello all, i was wondering what are some good ways to increase build quality?

Practice, practice, practice… seriously!

Make sure parallel parts of the structure are parallel. Make sure members that need to be at right angle are at right angles. Check drive shaft alignments often! If it they do not spin freely it is not aligned… or missing bearing blocks.

Tighten everything that needs to be tight to keep the structure shape and loose if you need to have movement.

Wiring should be neat and not easy to be snagged by other robots, or your own!

Label everything clearly and document it in your engineering notebook.

Check everything between every match and fix right away!

Every keps nut on the robot will become loose every time you turn it on. Be very aware of this.

Motor screws tend to come loose, too. Especially before finals.

Either use loctite or tighten everything, all the time.

Motor screws that come with the motors have locktite on them use those.
rubber bands are your friends,
Make sure your motors are secure and working right before the finals

how does one make sure parts are exactly parallel? because they can be off even if attached with a c channel it cant twist or be eneven

File well after cutting, also reduces how often the next person that grabs that piece injures themselves.

does anyone know what shoulder bolts do? somone mentioned them in a different thread, and idk what they’re for

Make sense?

If the structure twists, twist it back or replace. You asked about build quality, if the structure changes shape and impedes your robot’s motion, it is not the best quality.

i think you misunderstood me, what i meant was that if you have two parralel bars, and connect them via c-channel. they can be slightly twisted and you can no way of seeing it because its so minute, how do you solve this


yes i know what they are, i dont know what purpose they have, they dont fit through bearings, they dont hold things down particularly well, what are they for?

Short answer: Ruler is a good tool to use. Squares help.

From experience, I see structures that are not true better than students. Easiest to do is to find a really flat surface and place your frame on it. Inspect it closely, if it wobbles, you are in trouble - fix it. If you have a square, make sure the frame corners fits snugly. Having good reference points helps spot these issues quickly.

That said, I have missed big errors by not taking a step back and looking at the structure for my students. It is easy to get immersed with non-issues and failing to look at the big picture. Non-parallel structures cause drive shafts to flex/bend and gears not to mesh. In the long run, the structure will fail at the worst possible time, like elimination matches. Spotting small structural problems early and fixing them right away will really improve your team’s performance.

At least the way we use shoulder bolts is to help make sure things stay parallel and square. Because the shoulder part of the screw is almost exactly the width of the square hole, there is very little wobble at every joint. Use 4 shoulders at different places and you’re looking at practically no wobble at all. Also, shoulders slip in super easily unless there’s something wrong, so if you ever encounter resistance popping one in, you know something’s not quite straight.

So what about wiring the cords to the cortex? Any tips on that other than ziptiing the motor controllers to the metal? I’m probably the worst at doing it but the picture will show where I need improvement.

A couple of examples.


They would both make a field tech at worlds happy.

  • Good visibility of the leds.
  • Power switch easy to access
  • VEXnet key not obscured by metal.
  • Battery not hanging off and dragging on the floor.

On the first, I would add structure near all the sensor wiring for strain relief. Example 2 is awesome in that regard. Both are nice cable management. Personally I like the second one better de to lots of protection to the cabling around the cortex.

Thank you, those examples made it very clear. :slight_smile:

Bumping this thread because it will be helpful for the new people this season

By the way, I am unsure if bumping is allowed on the VEX forum, but I may be wrong…

This may be weird, but I improved my build quality drastically when I started using nylocks for everything possible, as well as having the 3 wide C-Channels for the tower and a bit on the drive. I also realized that using zip ties instead of screws to hold the motor together is very useful for very fast replacement and internal gearing changes for the future(Just a pro-tip)
Hopefully this helps some people :slight_smile:

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Bumping isnt (technically) allowed, so just dont say that your bumping it, just kinda mention sompthing in the thread