We’re about to rebuild our prototype and we’re wondering which is faster as far as speed of lifting goes a 6 bar or an elevator.
It solely depends on your ratio for the 6-Bar, but running the lift at a 2m 1:5 high speed should be fine assuming the build quality is good and that half-cuts are used for the 6-Bar.
Or use a double reverse 4-bar…
A dr4b does not fit our constraints. Also I should clarify that both lifts would have about the same build quality and both would have gearcratios optimized for speed. We’re windering which if you the two would most likely be fastest after a that.
6 bars are the way to go. There is yet to be a cascade lift that can rival the speed of any n-bar lift. Only issue to them is the swing of the arm, which may be annoying when trying to take caps off poles.
That took lots of tuning along with finding some custom parts like the spacers they used iirc. Overall, if you want a well competing lift that is also fairly speedy, a 6-Bar is the way to go.
Although it was fast, it was not even faster then most 2M dr4b’s.
I made a Cascade lift using the 99371A design, but with no custom parts, and the rest of my team made a 6-bar, the cascade was faster (this was using V5 on both designs)
I would recommend trying the cascade lift and see if you can make one that works but as someone who has attempted it before a six bar is easier to build and do maintenance to throughout the season.
i haven’t built a cascade yet but my 6 bar which is powered by 1 motor 1:5 is pretty fast. you should probably try to build a cascade first because the cascade is harder to build than the 6 bar.
There are benefits and downsides to both. A 6 bar is easier to construct and usually (not always) faster. However, a cascade is linear and easier to drive with. We plan on making a lightweight dr4b. Each design has upsides and downsides that will depend on your overall design.
You do not have to use custom parts you can just order the spacers from McMaster. Another good part of a cascade is it is scalable and also very stable.
Cascade all the way. 6 bars are usually ungainly and are a pain to position over poles to put on and remove caps. Like DR4Bs, cascades are linear motion, which is a blessing for drive practice.
It might be a blessing to have a linear lift, but the amount of time spent perfecting a cascade for even the smallest of heights along with the fact that DR4B’s can reach just as high with greater speed already puts the cascade far down in my lists of lifts to use in this game. if you really want a linear lift in a small confined space, then yes go for a cascade. But just be aware of the struggles that come with it…
These parts are illegal
If the spacers are equivalent in size and material they’re legal
IMO, I would use a 6 bar early season and a cascade lift or a small dr4b for mid to late season.
While identical spacers are certainly legal, so are many other spacers that are not Vex-equivalent. Take a look at rule <R7> c. With my highlighting the first sentence says, “Any commercially available #4, #6, #8, M2, M2.5, M3 or M4 screw up to 2” long (nominal), and any commercially available nut and/or washer to fit these screws." That means you are allowed to buy washers that fit any of these screws, regardless of material, so long as they’re commercially available. The commercial term for these spacers is “washer,” or more commonly “thick washer” or “extra-thick washer.” That’s how you find them in hardware stores.
Here are some McMaster Carr examples:
Nylon plastic (screw size, inner diameter, outer diameter, thickness):
No. 4 0.112" 0.206" 0.048"-0.058"
No. 4 0.115" 0.250" 0.057"-0.067"
No. 4 0.120" 0.220" 0.026"-0.036"
No. 4 0.120" 0.280" 0.026"-0.036"
No. 6 0.156" 0.312" 0.026"-0.036"
No. 6 0.156" 0.438" 0.035"-0.045"
No. 6 0.162" 0.312" 0.055"-0.070"
No. 8 0.173" 0.375" 0.055"-0.070"
No. 8 0.177" 0.408" 0.055"-0.070"
No. 8 0.188" 0.500" 0.035"-0.045"
They also have lubricant-filled nylon plastic, polycarbonate plastic, and UHMW plastic.
And there is plenty more variety of materials and sizes available from other vendors. You can also buy them too small for what you want (like No. 4 when you want No. 8) and drill them out with more readily available tools and probably with more ease than cutting the outer diameter down to what you want.