One bearing always loose on Trucks?

I had some trouble with squaring so took things apart and re-setting tension/bolts on everything.

  1. I seat the 2 set of tension bolts/nuts very slowly just so that the bolt doesn’t move back and forth anymore.
  2. I seat the stationary bearing bolts/nuts about 1/16th turn past seating.
  3. Put a piece of emt through.

The far bearing (see pic) is always loose while the other 2 are nice and snug. Do I tension BOTH tension bolt or just the one next to it (the one with the nut next to the stepper). Tightening both tension bolt/nut makes the other 2 stationary bearing very snug (can barely turn them without moving the truck on the emt if at all).

The 3d printed parts came from the store ordered a few weeks ago, all little circular printed spacer are intact.

Thanks

How loose? If it’s just a little (it’s close to the steel, but you can rotate the bearing by hand) it should be adjustable. If it’s more than about 1mm away from the steel, there’s something else that’s wrong there.

I would suggest a little more tension on the bolt that goes through the vertical bearing next to the stepper motor. Adjust it in tiny increments. 1/12 of a turn or less at a time. These bolts can exert a lot of force on the plastic, where not much is actually needed to make the necessary adjustment.

If the gap is large, I’d verify that I was using the correct size steel. The part that you have pictured is for 25.4mm, 1" diameter tubing. (I can see the “J” in the picture.) Otherwise, there should be no reason for the 608 skate bearing to be very loose…

… Wait…

EMT? Like 3/4" conduit? Okay, I thought that looked like a “J” in the picture, is that actually a “C”? If it’s a “J” then you have the wrong steel. “J” pieces are for 1" diameter tube, “C” pieces are for 3/4" EMT conduit. (23.5mm diameter.

Sorry I just used a stock picture from the build instruction just to show which bearing it was. I ordered my parts (23.5mm) from the store at v1engineering and am using 3/4" emt which is within 0.1-0.2mm.

It is just loose, no gap between the emt and the bearing but it rolls VERY easily, almost free. I just wanted to make sure it was okay just to put a bit of tension on ONE tension bolt instead of both at the same time like the instruction says.

I’m just trying to avoid any mistake during the rebuild to figure my squaring later on.

OK. Thought that might be the case. Yes, just a little tension at the bearing that is loose. Tiny increments, just until it doesn’t roll easily with finger pressure.

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