How do I connect a C-channel to a gear?

VEX V5 General Discussion
#1

The other day, our team was confounded over how to connect a C-channel to an 84-tooth gear, & we need the arm to be parallel to the ground. Help, please!

#2

With screws and nuts, or you could use zipties i guess

#3

there are holes in the gear

there are holes in c channels

you put a screw through both holes

and you put a nut on the other end

do this atleast 2 times

or you could use zipties

#4

Use 3/4 in screws, and place spacers between the gear and the c channel, so that the gear is not directly touching the c channel.

#5

I see you repeatedly asking simple, googleable questions. Why can’t you just search for pictures of how others have done it? Please do that before posting randomly on the forums.

#6

There are a lot of methods which depend on how the C-channel needs to be oriented, etc. But one place to search will be YouTube. I suggest you search for “Vex starstruck claw” since many of those claw designs used C-channels connected to gears.

Here’s just one:

#7

What’s the problem with that? The only thing I would bear in mind is that you need to be careful when mounting screws through a hole with space between it and the bar (where the gear is thinner).

#8

No problem, I’m just worried about the same thing you are. For a new team, I imagine it’s easier to add spacing such that the gear isn’t touching the c-channel than to worry about getting the spacing exactly right so that the gear isn’t tilted one way or the other.

#9

Instructions Unclear I stapled my hand to the robot instead.

#10

Instructions in clear, used zip ties instead of screws

#11

instructions unclear, i asked a question before attempting to find out the answer on my own via past posts or videos, or any other way @HowDoITurnThisOn?

#12

Instructions unclear, started a nuclear war, and now both hands are stapled to the robot.

#13

Instructions unclear, F o U n D S o M e W e I r D M e M e S o_O.

#14

You may also want to sandwich a bar lock on the gear to alleviate stress on the plastic and shaft. Not always necessary though.


(picture is larger than actual size)

#15

generally, you should be using circular shaft inserts, because they give you less friction, and that way you dont have to fight thoes to put them on the saft, and you can use 2" screws as shafts which are better and provide less slop

#16

If you’re using high strength gears, you’ll need a high-strength lock bar: https://www.robosource.net/38-high-strength-lock-bars-1x1-angle. These will keep gear hubs from stripping or gears from breaking at high torques.

#17

but who uses high strength axcels?

#18

We use high strenth axles on our claw for EXTRA GRIPPING POWER

#19

HS axles seem to have a lot more friction. Not just at the bearings but it seem like the lack of flex in the axle creates additional friction between gears.

#20

One thing to watch for is how many bearings you’re using. Industrial practice is to use only two bearings per shaft, any more and a flexible coupling or universal joint is required,. (We also usually use a flex coupling between the motor and the first shaft, if direct driving the shaft). Typical VEX robots have a bearing every time a shaft passes through metal. Regular shafts “flex” through the extra bearings and don’t bind too badly, but HS shafts don’t flex, and thus they bind in the extra bearings. This can be avoided by using only two bearings on the shaft, and drilling out oversize holes so the shaft doesn’t touch any metal that it passes through.