dr4b double reverse four bar CAD. Advice??

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#1

I’ve had success so far with a scissor lift this season, but over the holidays plan to switch to a dr4b. Here’s a cad model I made on google sketchup: https://3dwarehouse.sketchup.com/model.html?id=ude923359-20c3-4513-9041-6b0f45ddaa31 (To view it on the site, just click on the button with arrows.)

This is a rough model. I don’t have the hardware shown but it will be where one would presume it should go. The skyrise claw will stick out the back, on the c-channels attached to the conveyor.

4 motors, powered via the pinion gears on the middle vertical section.

Do I have enough lateral support? Anywhere I can save weight? Any tricks you know of?

#2

In order to view it, (if you haven’t already, you must download sketchup or sketchup viewer: [http://www.sketchup.com/download/all )

This is a rough model. I don’t have the hardware shown but it will be where one would presume it to go. The skyrise claw will stick out the back attached to the conveyor.

4 motors, powered via the pinion gears on the middle vertical section.

Do I have enough lateral support? Anywhere I can save weight? Any tricks you know of?](http://www.sketchup.com/download/all ))

Please post a few screenshots of the “sketch”

A lot more people will be willing to offer advice if there is less of a hurtle that they have to jump through.

#3

attached are pictures
Edit: the last three pictures are uploaded at really low res. But the first two are reasonable quality… I recommend that you follow the link and actually look at the model. (You don’t have to download a program, you can look at it directly on the site)
dr4b1.jpg
dr4b2.jpg
dr4b3.jpg
dr4b4.jpg
dr4b5.jpg

#4

seems like a very good lift and no problems I see. I would just make sure to do high torque axles when possible on the lift gears. they are under a lot of stress,

great job!

#5

What are the 15 lond C bars for on the top section of the lift? I can’t see the use, and they add extra weight. other than that, it looks good. Heavy, but sturdy if built well.

#6

its a skyrise 1 bar (chain bar) scorer without chain in the cad model.

#7

No, the 1x5x1x15 c bars , there are three of them extending from the top of the upper 4 bar.

#8

I might consider making the first tower out of 5x c channel. it will give you less flex in the lift and the arm will move and turn with the chassis more than if it is just a 2x.

also doesn’t look like you have a full chassis, but making sure that the chassis doesn’t have too much flex where the tower attaches. it is going to make a big difference in how stable the actual arm is.
we put a 2x c channel toward the front of the chassis going from one side to the other and it made the lift a lot more solid because the flex was actually coming from the chassis, not the lift.

is the chain bar on the top of the lift designed to move skyrises from the autoloader to the base?
if so, how are you going to fit between them like that?
I feel like the back of the arm would hit the auto loader every time it tried to rise due to the swinging of the first 4 bar layer.

do you have it built yet? love to see it!
good luck!

#9