So we have a DR4B and we’ve recently had some troubles and I’m stumped. I’ve checked the internal ratios and even put it on an rpm reader and they’re all torque. We have the same tension on both sides and it still prioritizes on the right side while lifting down. The programming is as good as it can get so I’ve ruled that out. Pls halp.
Make sure both sides of your lifts have very little friction. One of the motors might not be working check that as well.
“lifting down”. Anyways, we have the same problem. What we are doing is we’re going to add some “X” braces, I’ve heard this is the best way. Also make sure each motor is working completely, no damaged internal gears etc.
My lift had the same problem. I use long screws as axles, and the tightness of each screw was slightly different. One side of the lift was noticeably stiffer than the other, so I had to spend a lot of time checking each joint’s tightness individually. Check the stiffness of each joint and make sure it’s symmetrical.
I think cross bracing, though effective, is just a band-aid solution. The underlying problem, whatever it is, is still there. That said, cross bracing is still a good idea, because it will make your lift more stable and robust overall, but I would recommend trying to solve the underlying problem as well.
Bracing is key, and make sure all of your motors are the same type(hs, torque, or turbo)
Checked internal gearing and one was completely stripped. Replaced it and it’s now working. Thanks all!
FWIW
If your gears stripping you may want to get high-torque gears - they’re way more powerful than the motors can spit out!
Our 9:1 gearbox twisted a 1/8 axle to where it looked like wrought iron ! A thing of beauty!
If possible I try to find a way to tie the two-sides together - usually an axle and sometimes need a coupler. Stay away from VEX universal joints unless necessary.