I am building a new Z axis, and I wanted to try attaching my z axis to my idler bearing by tigheneting a nut on both sides of the idler bearing. So I am using a 10mm threaded rod, and a bearing with a 10mm inside diameter. and simply tighten a bolt against eiether side of the bearing to lock it in place. It seems to spin very nicely when I move the motor by hand. I also have access to a lathe, and I am wondering if there is any benefit to turning down the threaded rod so that it fits very snug inside an 8mm or smaller ID bearing vs. simply tightening the bearing to the rod via two nuts? Any insight would be appreciated. https://reprap.org/forum/read.php?14,232225,232225#msg-232225 Wed, 16 Sep 2026 17:43:17 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?14,232225,256739#msg-256739 https://reprap.org/forum/read.php?14,232225,256739#msg-256739 -------------------------------------------------------
> I am building a new Z axis, and I wanted to try
> attaching my z axis to my idler bearing by
> tigheneting a nut on both sides of the idler
> bearing.
>
> So I am using a 10mm threaded rod, and a bearing
> with a 10mm inside diameter. and simply tighten a
> bolt against eiether side of the bearing to lock
> it in place.
>
> It seems to spin very nicely when I move the motor
> by hand.
>
> I also have access to a lathe, and I am wondering
> if there is any benefit to turning down the
> threaded rod so that it fits very snug inside an
> 8mm or smaller ID bearing vs. simply tightening
> the bearing to the rod via two nuts?
>
> Any insight would be appreciated.



If I was going to build this machine, I'd go with "Precision Acme Threaded Rod".:

[www.mscdirect.com]

Or, is there a reason you guys use plain/standard, theaded rod?:S


Not a bad price for this precision.....]]> Metalmann Mechanics Sun, 20 Oct 2013 03:15:13 -0400 https://reprap.org/forum/read.php?14,232225,237826#msg-237826 https://reprap.org/forum/read.php?14,232225,237826#msg-237826
In addition, if you measure the major diameter of the 10mm thread you will find it is much less than 10mm. When you bolt it up it is always eccentric in the hole. Machining down to 8mm is a much better idea, but you may still get problems as the threads on cheap bar are often "drunk", so a nut travelling along the thread does not move linearly, but wobbles about (Like a drunk hence why it is called such in engineering).]]> martinprice2004 Mechanics Tue, 20 Aug 2013 08:26:07 -0400 https://reprap.org/forum/read.php?14,232225,237778#msg-237778 https://reprap.org/forum/read.php?14,232225,237778#msg-237778 waitaki Mechanics Tue, 20 Aug 2013 04:46:12 -0400 https://reprap.org/forum/read.php?14,232225,237567#msg-237567 https://reprap.org/forum/read.php?14,232225,237567#msg-237567 AVRkire Mechanics Mon, 19 Aug 2013 09:56:04 -0400 https://reprap.org/forum/read.php?14,232225,235993#msg-235993 https://reprap.org/forum/read.php?14,232225,235993#msg-235993 jkoljo Mechanics Thu, 15 Aug 2013 02:10:54 -0400 https://reprap.org/forum/read.php?14,232225,232225#msg-232225 https://reprap.org/forum/read.php?14,232225,232225#msg-232225
So I am using a 10mm threaded rod, and a bearing with a 10mm inside diameter. and simply tighten a bolt against eiether side of the bearing to lock it in place.

It seems to spin very nicely when I move the motor by hand.

I also have access to a lathe, and I am wondering if there is any benefit to turning down the threaded rod so that it fits very snug inside an 8mm or smaller ID bearing vs. simply tightening the bearing to the rod via two nuts?

Any insight would be appreciated.]]> AVRkire Mechanics Fri, 02 Aug 2013 18:45:51 -0400