not sure if this is the right place for this post.
This year, we are using a conveyor belt system for ball pickup, and we have been planning on using surgical tubing because we have some lying around from 2014. I have seen a lot of other teams using translucent polyurethane tubing instead and I was wondering if there is any reason to use one over the other. I am slightly worried that the surgical tubing might be too elastic.
I’ve seen it done both ways successfully
Our team has used both over the years.
We have stuck with Polycord simply because they last a lot longer.
Our surgical tubing on older robots are all corroded now. Our Polycord for our 2012 robot would still work like new.
This is the perfect place for a post like this don’t worry. Our team has found that poly cord works better in a conveyor belt system. Usually we only use surgical tubing when we want to use its elasticity (we used it for a quicker can grab in recycle rush). We recently threw out the conveyor belt idea for space and we used poly.
If you get hollow-core Polycord you can use connectors to link ends instead of having to melt ends together. This alone was enough of a selling point for my team.
I personally would think surgical tubing would be a bit harder to work with and wear down faster but I have no personal experience with using for a belt system.
After using surgical tubing for our ball intake in 2012 then switching to poly cord half way through our competition season. I will never use surgical tubing again for a drive system. We were replacing at least 1 surgical tubing belt on our intake after every match. Switched to polycord, and we never had another problem. Stuff is skookum as frig, and will chooch match after match with no fault regardless of how many RPMs you are spinning it at.
They both can totally work, but surgical tubing’s elasticity tends to work against it here. You have to pay more attention to it, and it can wear down quickly. It’s not really the right tool for the job.
Personally my preference is for the flat polyurethane belting on McMaster, which is IMO a bit easier to work with than the round stuff and a little grippier.
Chris, we’ve used the poly cord for many year but are using the belting for the first time. Is the % of reduction still the same, about 6-8%? By reduction, I mean the amount that you cut off to ensure an elastic fit.
No, you want to start with a lot less. I don’t have an exact number, but I would guess 2-3%. The belting is much less stretchy and stays much tighter in place.
You can always cut more off later, but putting an extension onto an existing belt isn’t as fun / clean. You can even weld these belts in place if you have some clamps and apply plenty of extra tension to the opposite side.
Thanks for the input. What kind/brand of tubing would you recommend and where would I find it?
We have had good luck with this stuff: