We just added two more motors to our 2-bar lift for a total of 6. It’s faster but now the gears slip and make beautiful clicking sounds. I’ve heard a 6-motor lift should be able to pick up ~4 or 5 stars at a time but we can barely pick up 3. I’m sorry if this is a simple question but we would really appreciate any tips. Thank you in advance?
Attached are pictures of our lift gearing.
Edit: My apologies for sideways photos.
Try to make your towers closer. Ours are an inch and 3/8ths and we never have slipping problems. We have hs gears attached to c-channels just like you do.
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Spacing does look a little loose. The closer together the towers are the better supported the shafts are, thus making them less prone to bending and the gears skipping. I would also consider moving one of your motors to the same shaft as one of the other powered pinions to take out an idler gear to reduce friction.
Are you using elastics at all?
Yes we are, but we aren’t sure they are actually helping. Could you take a look? We can lift comparable weight with or without them.
Just like everyone’s already mentioned, it’ll help to tighten up the spacing a bit. A quick fix that might work for now would be to switch the bearings on all the other gears to the inside of the tower and potentially even mount them on spacers or standoffs to better support the axle with the bearings close to the load.
There’s your problem. The rubber bands aren’t really helping at all, they’re just pulling the lift toward the point it rotates. Ideally the rubber bands would pull upward on the bar. This can be done by raising the mounting position on the towers above the arm, or using a four bar below and pulling up on that.
The possible rubber band positioning are marked in yellow.
It also looks like some of your bearings are really lose. What are you using to attach them instead of screws?
We have pop rivets on the bottom ones and screws w/ nylocks on the top ones. Should we not use pop rivets?
@Cnidarian1 personally, i wouldn’t recommend them, i’ve not had any good experiences with them they always seem to fail when they dont need to
Try to spread your motors out instead of gearing them in series (in a line); instead of gearing your motors below one another, try having all 6 12 tooth gears drive the 60 tooth-arm-gear directly.
Additionally, those white nylon spacers actually have a larger outer diameter than the inside diameter of the 12 tooth gears (sinply put, those white spacers may actually move the gears apart and cause slipping if that 60 tooth gear gets caught in the spacer.
Out of curosity, why do you have T gussets under your bearing flats. If it’s for spacing, the less pretty but more efficent method would be to mount the screws backwards as the screw heads are smaller than most nuts.
I agree with @Amadeus in that your gearing would be better if you used a planetary gear box (motors around the gear). There are a couple of ways to do that. Here is a picture of one example. You can also look at team 62 for another way to do it…
I would put all the gears closer together and it should also decrease friction.( use elastics)
Just whatever you do, dont link two 12 tooth metal gears together, the friction is 2x worse than on a normal plastic gear
If you can’t make your towers closer you can do what I did… Your problem is that the gears are separating… ziptie the axles together…
You need to fix all of the bearings. Do not use the pop rivets, but screw all of them in with the normal keps, if you tighten them enough they will hold fine. Make sure that the bearing cannot move because then the axel in it will move under stress and click. Like others said, also make rubber bands more efficient, minimize the spacing in your towers, try and make gear train shorter, Screw The Top Gear Into The Arm C-Channel!, and maybe add posts in the towers to increase stability.
is that really true? My lift has 2 metal gear connected and it can lift 6+ stars or 2 cubes 5:1 Hs
So is it worth changing? How much of an effect does it have?