What is your cad level?
Do you also put screws/belt ?
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We do everything but rivets and wires, and that’s only because I haven’t found a rivet cad model I’m happy with yet.
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If you want rivet cad model I can send you 
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Does the rivet need to have the hammer persuasion marks modeled? XD
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Haha not quite, but I’m also kinda particular about the CAD looking good.
the only thing we don’t put in cad is wiring
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Our team typically puts everything except things like Rivets, screws, wires, other fasteners, etc (we’ll make an exception for screws in really tight areas). We do that to prevent confusion among the assembly team.
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We assemble the cad barebones, then add screws, bots, etc. after that. in 2018 we had the rigging for our elevator all modeled out, but none of our cadders this year were as experienced as they were.
I used to be more religious about putting screws into models but I’ve backed off a bit in recent years due to how laggy it can make assemblies when you have so many fasteners.
That said, I’ve also been burned by not adding screws and encountering clearance issues when actually building the robot as a result, so I may be more inclined to do this in the future.
I’d love to model in wires too but I haven’t found a good/easy way to do this in Inventor that doesn’t end up taking far more time than it’s worth.
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Team 1672 is proud to use Whiteboard CAD with a high level of detail such as “yeah that’s about square” and “these gears are not to scale but here is the vague ratio for them”. One day we’ll buy a protractor. In my dreams, OnShape, but not enough push from everyone else.
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Man, you guys should really use Onshape. It’ll let you make both 3DP and CNC parts, and make organizing designs much easier. Surprised y’all haven’t, either, given it’s free and easily accessable.
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This is assuming one already has access to a 3d printer or CNC machine 
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Fair, but I’d highly suggest getting a 3D printer at least because it allows you to make custom parts really easily (And Lazily). Besides, even without having a 3D printer, CADding your robot will probably prevent a lot of silly mistakes when manufacturing.
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If you buy McMaster hardware, put it in cad.
Assembling mechanisms takes barely an afternoon when you can go straight to the McM boxes, pull the bag with the matching part number sticker on it, and install. Definitely one of the most revolutionary things we did for CAD while I was a student.
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I think I’m like a bit above average? Usually I do belts + bolts, no rivets tho. Generally try to avoid as many interference issues as possible and having belts/chain modeled looks pretty. It takes like 15 seconds per belt with feature scripts parametrically so there’s no reason not to.
At the same time, I’ll happily use simplified models to save precious load time such as standard grid pattern instead of maxtube in cad, and low poly sds modules
(For cad reference, I solo designed 7461’s 2022 off-season, and both 2023 on season robots) (won’t do that again)
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I’m a pretty new CAD person, this was my first year CADing. I think I did somewhere between 40-60% of 112’s 2023 bot and recently designed a modification to a swerve module. No bolts, mostly. I put in bolts on the swerve module because it’s very highly detailed and important, and i was bored.
(Gripper which I designed ~60% of)
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I’ll make an argument for bare minimum fasteners. In my experience professionally, adding all fasteners makes lower powered computers lag unnecessarily, takes CAD man hours away from actually completing the robot, and serves very little purpose. Use the time for CADing electrical. If you have the time to burn, and your computers/software don’t mind all the extra entities then go ahead I guess, but I’m not doing it.
I do however strongly endorse CADing fasteners everywhere clearance is a concern. If you have any really tight areas, or fasteners near moving parts, CAD them.
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Agreeing with some of the other posters here. I’ll CAD extra detail (such as fasteners, belts and chains) when I’m concerned clearance, and occasionally when trying to figure out what length of bolt we need for a given application (so we can reference part numbers/sizes quick and easy in the future).
Belts/chain I specifically encourage people to draw, as I’ve been burned more times than I’d care to admit when I havent modeled them, and ended up having major interference issues down the road 
(interference that would have been very obvious had the belt or chain been modeled in CAD).
I absolutely hate it when every single bolt/rivet is added in CAD, as it drastically hinders the performance of whatever computer you’re using (be it the latest and greatest desktop, or a 6 year old hand-me-down mid-grade laptop) for little to no upside.
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Agree, but one thing I’ve seen (ok, done) is… Designing holes for bolts in tube or other extrusion that are too close to the perpendicular walls for the nuts to fit. Including the nuts and bolts in the CAD would reveal the interference.
(Or the design works so the nut barely fits if the wall thickness is 1/16th, and then 1/8th wall thickness is inadvertently used by manufacturing… Not a design problem so much as a “hand-off” problem.)
Net: It’s good to pay close attention to potential fastener / tube wall interferences. When in doubt, include the fasteners in the CAD if you feel there’s a risk of interference.
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Last season, we did what many teams did, and CADed all components except for rivets and “common” bolts or bolts in areas where clearance wasn’t a concern. However, we are considering making a change going into the next season to fully complete the cad with all bolts. There are a few reasons for this:
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For designers, it can be easy to forget clearance for hardware or even spot conflicts if the hardware isn’t in the CAD model, which can lead to assembly issues or unnecessarily complex assembly processes. Mandating all hardware in the model makes it easier for designers to see issues and fix them before the parts are made.
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Having a fully complete CAD model means that when the BOM is exported for the build/assembly team, they can be confident that every part is accounted for. No bolts need to be cut down and no holes need to be egged out to fit a larger bolt since the correct size bolt just wasn’t at the lab. Our team doesn’t own every type of bolt, so omitting many bolts from CAD means that we commonly are missing the correct bolt, which makes assembly take longer and is more confusing for newer members.
I’ve found that adding hardware doesn’t make the assembly much laggier if I use simplified hardware (McMaster has download files for simplified bolts and nuts which omits the threads), so that’s not one of our main considerations.