How snug/loose should non-tension bolts be?

Mostly Printed CNC - MPCNC Troubleshooting
1

I’m assembling a Burly build that I printed myself, but all the hardware is from the V1 store. (I got a full 525 build from the store in 2016, but I wanted to upgrade to a Burly and started printing just before the Primo design came out.) I got everything working but there’s vibration along both axes. From what I’ve read here, the main culprit is usually too much tension.

I actually got a torque wrench to tighten everything to 5.5 N-m, and I’m pretty sure that’s roughly how tight I had everything during my first go-round, but I’m trying to make sure it’s all as loose as possible to make sure I’m not causing any problems for myself.

So, my question: when it comes to the bolts that only hold the bearings on (not the tension bolts), if the bolts are able to turn freely, is that too loose? Should I snug them to the point where I can’t turn them by hand? (Again, this is all still under 5.5 N-m per the torque wrench.)

2

You don’t need them any tighter after the bearing can stop coming out and in. If the bolt turns, that doesn’t matter.

3

I think 5.5Nm is too tight. I’ll need to get my torque wrench out to check, but that’s the sort of tightness (I think), I’d do handlebar stems on my mountain bike and that’s waaaay too tight.

I tighten mine up when I can feel pressure coming back through the fingertips. Difficult to describe, but when I feel it pushing into my fingertips, I think that’s enough. I don’t grip the spanner or allen key with the palm of my hand and do a big heave on it. It’s all delicate touches almost as if you’re stroking it.

Rob

Rob

4

Thanks!