Double reverse chain bar?

I was considering different lift options for my robot and I realized, shouldn’t a DRCB be a more effective lift? It would theoretically use half the metal, while remaining a linear lift. Any experience of thoughts?

If I’m understanding this right, this is actually very similar to something I have been thinking of for a few weeks. A danny lift. I don’t have the whole concept ready yet, or even something that I can explain, but basically the danny lift with a claw on the top piece.

Sort of, but it is literally two chain bar lifts put together like a DR4B.

I think you’re misunderstanding. I’m still not exactly sure what a danny lift is . . . I’m not quite convinced they’re real, but I don’t think they use chain bars

I think people generally prefer 4 and 6 bars over chain bars even though chain bars offer the same height with less metal, but it’s worth a try and I think other teams will be trying this this year as well.

‘Danny lift’ = DR4B I think

Kind of, the mechanism in the middle is much different though.

I would be concerned about slop, but that could be avoided.

The main reason this happens is due to lack of tension and just due to the nature of some VEX parts, but I think it could be resolved.

Not gonna lie I laughed so hard when I saw this thread. :smiley:

I made a DRCB, I can assure all of you that’s it’s possible and works. It was decently strong, even with some other bracing constraints specific to my design. You are all overestimating the slop that chain actually gives you haha.

Also, a Danny lift is not even close to a DRCB, It is literally just a Dr4b with offset bars so that it can go all the way vertical. I’ve heard it also referred to as a vertibar 4 bar. The original Danny lift video uses chain to power it, so I can see where the chain bar misconception came from, but in reality you don’t even have to use chain to power it.

Just on the topic of danny lifts and double reverse four bars, is it more efficient to mount the motors on the base of the lift or on the second stages mount?

If the chain snaps you’re screwed…

Same for lots of things in VEX. The only question is, is that a likely occurrence? High strength chain is very strong (if I remember correctly, it can hold 60 pounds). So you would have to be doing it wrong to have a problem.

~50 pounds, based on our extremely unscientific testing. Also, I assume you’d have a set of chain on either side of the lift.

Yep, 50 pounds.

Plenty, either way!

Though I haven’t done any math calculations or anything, I think that it is more efficient to put the motors on the base of the lift. My reasoning for this is that with the motors on the lift, they have to lift their own weight as well. With the motors on the base, you don’t have to lift the weight of the motors as well.

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LOL. This is funny. My kids have been talking about doing this for weeks. They are starting with a single chainbar trying to figure out load balances and limitations and motors needed based on weight.

What they have in mind is a bit different than the “Danny lift”.

It will be interesting to see if this becomes the new meta

Spoiler Alert We’re strongly considering a DR4-CB lift. Yup. Reverse 4-bar and chain bar. We would gear it to work the same way as a DR4B, but we would be carrying less weight than a DR4B would. Although I guess it would be called R4B-CB lift.