FTC Tips and Tricks: Comparison of Lift & Linear Movement Mechanisms

[@alkali836]

some things we've learned over the years using mgn7, mgn9, and mgn12 slides: - the rails are extremely hardened steel and are difficult to drill and cut. we've used an angle grinder to cut them, but I suspect they'd be very difficult to drill. if possible, check in cad to see if a few holes coincide with the kit parts you're using, use custom parts for mounting, or use t-slot extrusion. also, you'll also have one less thing to worry about if you design around a stock length instead of cutting. - the carriages are really short compared to the overall length of the slide. mgn slides only have 30-50mm of overlap between each stage, while misumi slides have at least 120mm. this small overlap increases travel, but it also decreases rigidity. these slides were designed to be within a gantry of a 3d printer or cnc with little to no lever arm on them. if you make a multi-stage lift with a moderate amount of load on it, you should have two carriages spaced apart on each rail to increase rigidity. if the last stage doesn't have much of a lever arm on it, you can use 1 carriage for it. - if you don't want to plumb the depths of ebay, you can get mid range slides from amazon or zyltech that are marketed towards hobbyists. - mgn9s are the best size for the vast majority of ftc applications. mgn7s are relatively weak, difficult to source, and difficult to use since they use m2 screws. mgn12s are nice for some things, but they're big and heavy. mgn9s are a nice middle ground, and they use m3 screws. - these are hands down the best slides we've ever used. they have virtually no slop, and if configured properly they can handle very high loads without drooping. the only reasons they aren't more common in ftc are that they're relatively expensive and difficult to use, and for many designs the benefits they offer aren't necessary.

[@nv7213]

You should add Gobilda viper slides to the list

[@owen9573]

🔥🔥🔥🔥

[@burkillkouren5088]

Hi! My team is using a REV Robotics continuous, linear, vertical lift (without door slides). We only use the materials in the REV Robotics Linear Motion Kit. The lift had been working perfectly and smoothly until a couple of days ago, when the whole lift started experiencing significant friction and some internal sliders started getting stuck as a consequence. The main problem is only on the way down. Do you have any tips or suggestions to make the lift go more smoothly?

[@Brainstormers8644]

It's tough to know without closer inspection, but we've had problems where the plastic sliders become misshapen, maybe due to stress or temperature changes. Are there some portions of the lift that are more sticky than others? Have you tried to replace the sliders? If you email photos or videos to us at brainstormers8644 @ gmail.com, we might be able to offer other suggestions.

[@d1joshy]

can you guys provide cad for the pieces with bearings used with the misumi sar230 telescopic side rails?

[@Brainstormers8644]

Unfortunately most of the team have graduated and have moved on to college, so we do not have the CAD models.

[@d1joshy]

@@Brainstormers8644 oh, that's fine, thanks.

[@quinn.mcginley]

wait is that how lead screw is pronounced?

[@Brainstormers8644]

Yes