Issues with arm raising

Ok, so I’m having issues with lifting the arms on my robot, but this happened to the axle when I tried a gearing larger than 7:120190917_190050 also, I have to zip tie it so it doesnt strip because the channels are tilted20190917_190108 Therefore, I wouldn’t love to redesign and I need a way to fix this before my competition

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do you have more pictures of the robot?

woah thats kind of wonky ngl.
your first priority should be getting all your c channels straightened out as soon as possible.


thats kinda what I was thinking, but wanted to see more shots of the bot to get a better idea

Also, really cool to see you xenon, Ive read a lot of your comments in other forums, you’ve been a huge help

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20190917_192151 20190917_192145 20190917_192138

vex forum is my home. I always try to help.

so yeah your bot isn’t as wonky as the first picture suggested so thats good. the main things that immediately stand out to me are the leaning lift towers, and the cantilevered gears. you always want your gears to be supported on both sides, otherwise you’ll get crazy friction. this may mean you’ll need more lift towers, which should be perfectly upright and secure. make sure you’re using bearings.

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Do you mean add another channel (smaller) to the gears holding the arms?


Also, @Xenon27 does this mean possibly I can do this with the wonky channels?

Well, as with all bots in this design, including mine, lifting the rollers can be tricky because the arms are very long, and the rollers are very heavy. I have bands helping to lift the arms, taking some strain off the motor and gears. I think as xenon said, your other biggest issue is the tower seems wobbly, and that may be creating friction, making it harder to move. Try straightening out the tower so the axle isnt twisting, and make sure nothing is holding the arms down (nothing is catching), then maybe use bands to help lift the arm, it will lessen the work of the motors


If the tower supports for the lift arent straight, you’re going to have friction. Best to solidify your arm base first.

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exactly. I had issues with this in past years, it may seem like a small thing, but is important to be done properly

Does anyone know the best way to make sure it is secure(the base for arms) so it can be sturdy?

Attach it in as many spots as possible. bolt it from the top, side bottom, and use as many screws as possible. I would also use a piece that angles from the middle of the bot to about halfway up the tower. Triangles help add stability to perpendicular pieces. I also like to use a 5x to connect the base so they will always be parallel, even if it wobbles a bit

Give the towers more mounting space, one hole and zipties arent enough…


Lol, fixing that now, so I’m thinking to move the towers out, intakes in, and secure it.

I hope it works for you. Goodluck

Use 90 degrees gussets if you’ve got any. Bolted c channels also work

Also, zip ties to keep ur robot together is just a robotics meme in both vrc and frc. DONT DO IT!!! My suggestion would be to make those c-channels parallel (innovative suggestion amirite?). But honestly, this is super important. Also, if u can, use a high strength axel. I’ve never seen a single one of those bend ever except in a high pressure environment like a catapult or puncher. An extra c channel from one tower to the other will make a world of difference.


Ok everyone, made adjustments, and I dont know where to attach the intake arms where it still works with a lock. It’s a lot more sturdy, and there is a lot of space, but the sweet spot seems to be where the channels are. The arms look like this20190917_215605 20190917_215554