Rubber bands & Standoffs


#1

We are a learning team and we started using rubber bands on our 4 bar lift to help with the weight and positioning. However, it seems as if our standoffs or screws are bending. Is there a way to do the rubberbanding to prevent this or any other better method. We currently just have standoffs with the 4 sided pieces connected to keep the rubber bands from falling off.


#2

Depending on how much space you have you could reinforce the standoff with a short one-by making a triangle with the c-channel. You could also stick the rubberbands through the holes in the c-channel and add something to the end to keep it from coming out. The simplest solution, though, would be to have multiple spots to mount the rubberbands, rather than putting them all on one standoff.

Also, I would consider switching to surgical tubing, as it keeps it’s stretch much longer and is generally much easier to work with. We use it on our catapult and we’ve never had to replace it in the months we have been using it. It is also much harder to snap compared to rubber bands.


#3

How many rubber bands are you using that your standoffs are bending?


#4

If you could post some pictures of the problem, it would be much easier to help you. Thanks!


#5

I currently do not have access to the robot but will do tomorrow.


#6

I am currently using 2 standoffs with 3 rubber bands on them.


#7

Keep the rubber bands as close to the c-channel / half-c channel / whatever lengths the standoffs extend from. The further out the rubber bands are on the standoffs, the more torque they cause.


#8

I think the best way to do it is to have a black bearing mounted on the arm with two screws on the outsides with the large white spacers. I hope you can figure out what I’m saying because I don’t have a picture right now


#9

You could try putting a lock nut on the screw or standoff that is holding the rubber bands. this has helped me a lot with tension issues like this in the past and helps keep things tight. https://cdn.discordapp.com/attachments/283783289796427788/500133003826298890/20181011_212914.jpg