My team is relatively new to vex and I’ve heard that chain drives are easier to make, but are flimsy. Is this true?
I would recommend using a gear train instead of a chain drive especially in VEX V5 as the speeds at drive train will rotate at will show considerable slop in a chain drive from my previous experiences. Also chain can snap which will render your drive train useless if the latter occurs. I would recommend however doing an experiment yourself to see which drive train fits your play style better.
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Thanks! This is good to know.
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Chain Drives are not easier to make. its about the same. chain drives have less moving parts but it really doesnt matter. Some big cons of doing chain drive over a gear drive is that chain drive is more prone to failiuers like chain snapping meaning that you would completley loose the ability to move arond on the feild. there are other issues that arise like if the chain is tensioned incorrectly you could have to much tension resulting in lots of friction or you could end up wit hteh cain to loose meaing when you change directions really fast or try to push around a heavy robot the chain will skip making it more prone to breaking or you just wont be able to actually get your wheels to spin meaning your gonna loose all pushing battles. i would take a look at this topic when deciding what drive set up to do. its show all kinds of gear train layouts for all kinds of speeds.
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Chain gives you more gear ratio options and some layout flexibility compared to gear only drive. However, you have to make sure there is no bad loose links and it is neither overnighten nor sloppy.
My best experience with drivetrains was combining multiple motors power with gears to the back wheels and then running the chain to the front wheels. Which gives plenty of space to build rigid base.
With good build quality controls you should have no problems using chain for the drive.
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Just be careful with chains. Last year our 2nd gen robot used tank treads and had big issues with chains breaking and getting the chain tension right was a pain
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the ratio part is honestly just straight up wrong, you have more gear ratio options to run on each wheel size than sprocket speeds. further proving my point, the chained drivetrain is forced to be on 4-hole spacing while geared drivetrains can run 3-hole (the amount of holes between each drivetrain pod).
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Adding on to this, in Spin Up I used a chain drive which broke during the state championship, nearly throwing us out of elims. Chains are easy to use, but I wouldn’t count on them holding up for an entire competition.
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Interesting, looks like multiple people have had reliability issues, any idea if they’re easy to repair?
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It’d just come down to replacing the chain—might need to only be a couple pieces, but depending on the degradation and damage, you may need to repair the whole chain.
Our first year we did a half-chain half-direct drive. It is very easy to mess a chain up is what we found out, because the way we built our robot caused the chain to always be behind the direct drive motors (basically meaning our 4-motor drive had 2 really fast and torqued wheels and 2 really slow and weak wheels).
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The biggest issue with repairability of chain drives in my opinion is that a good drivetrain has each side pretty thin. Usually 5 holes is a good standard, 6 if you want to use thick gears. If you want to make the thinnest drive possible, your chain will probably be tucked into a c-channel if you want to just chain wheels together and gear to it in other places, and in that case the chain will be very difficult to repair. However, if you do a bulky, thick drive side and your chain has plenty of space to mess with it, the repairability is fine.
However, all this is adressing repairing it if it breaks, and chain drives are more likeley to break. So if you dont want to deal with that at all, probably use gears.
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Repairing the chain is quite easy but its the fact that in a match you cannot repair, rendering your robot useless and unable to participate in the match.
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There were a number of chain vs gear discussions in respect to designs tailored to the specific games before … but, basically, having access to chain, in addition to gears, is giving you more options.
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Chains will snap. Anticipate it
For your drivetrains I would suggest avoiding chains as if they snap it can jam up or it can completely destroy your auton. Use gears on your drivetrain.
For other mechanisms, I would suggest doubling up. If you have a roller intake have two chains to the mechanism so that if one chain snaps you can still operate the intake. Redundancies are a necessity whenever you use the chains!
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I totally agree w/ this. Generally, sprockets must have the same amount of tooth, and chains must be tensioned for max efficiency. However, VEX chains tend to snap. I’d recommend a gear drive, a bit more friction but way more horsepower.
chain drives are probably a little easier to make than geartrains, and they offer more flexibility in terms of spacing.
however, it is hard to run a centered traction wheel, and if the wheel jams, the motors can provide enough force to break the chain.
honestly, I don’t see it this way, chain is a lot more prone to issues than geared drives are, and bent axles and broken bearing flats are still an issue in both.
1 drivetrain is fully out of the game when the chain breaks, but if an axle bends on a geared drivetrain, you have a little bit of veer in a different direction.
I am interested as to what you mean by more flexibility in spacing as running chain drive forces teams to have to use 4-hole spacing for their drivetrains, and the friction gained from gearing together drivetrains is negligible, while also removing a lot of slop introduced by chains.
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I see a lot of people replying saying gear trains provide friction but a well built drivetrain barely has any friction compared to a chain drive where even a well built chain drivetrain has worse friction and overall just building around a chain drive can be very bulky.
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what exactly do you disagree with? i never said that chain drives are less prone to issues. in terms of spacing, you have more flexibility in terms of how far apart your wheels need to be.
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just your viewpoint on the chain, as the way you made your statement made it seem as if geared drives were inferior.
the spacing argument honestly does not hold much weight because if the spacing is not working through gearing your drive, something else is off on the bot as there should be no reason the spacing available to someone through gears is too tight, and as I have previously stated, chain introduces a lot more cons than the pro of having the access to mounting wherever you want.
Hope this clarifies!
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