G0704. Strange noise coming from the head.

[Alistair Spence]

I'm getting a somewhat random knocking noise coming from the head of my G0704.
I can hear it at the upper end of the low speed range, but it's most obvious when I shift into the higher speed range and run up to max. speed.

It sounds like maybe teeth not meshing properly, or maybe something loose on a shaft. Hard to tell. It's intermittent.
I can hear it above the background motor noise but I wouldn't say it's particularly loud. I am concerned that it could lead to bigger problems so I'd like to figure it out before I damage anything.

I've been using the mill and it seems to be performing well. I'm getting good finishes. There's no slop in the spindle so I'm guessing it's not a bearing noise.
I've studied the diagram in the manual but I think I'm going to need to pull the head apart to get to the bottom of it.

Anyone have any experience with this kind of noise on their machine?

Thanks for any help on this.

Alistair.

[hoss2006]

There is some clearance between the splines of the spindle and the splines of the 2 gear assembly, part #'s 206 ans 246 in the parts manual.
This is how power is transferred to the spindle and allow quill movement.
It can rattle at times but isn't anything to worry about.
This is likely the cause of the noise, it's not uncommon.
Hoss

[Alistair Spence]

There is some clearance between the splines of the spindle and the splines of the 2 gear assembly, part #'s 206 ans 246 in the parts manual.
This is how power is transferred to the spindle and allow quill movement.
It can rattle at times but isn't anything to worry about.
This is likely the cause of the noise, it's not uncommon.
Hoss

Thanks Hoss. The word rattle describes it exactly. When I grab the spindle by hand and turn it back and forth in quick succession I can feel the lash that you mentioned. I figured that was normal and was actually wondering if that might be the source of the noise. It makes sense that it probably is.

Sounds like I can just keep on machining, which is good to hear.

Just for future reference, can anyone point me to a thread that details head dis-assembly? I figure I'll need it at some point. I'm interested in knowing if there are any specialty tools required, or any pitfalls that I need to be aware of when taking it apart.

Thanks again.

Alistair.

[hoss2006]

I worked with Michael in changing his spindle bearings starting here and it shows a couple wrenches
that can be made to help with removal.
http://www.cnczone.com/forums/bencht..._my_x2-20.html
Pics below of the upper spanner wrench I made.
These couple videos show how to remove the spindle and intermediate gears.
http://www.youtube.com/watch?v=hP-XvbV7Pc4&feature=plcp&context=C445fd85VDvjVQa1PpcFMgf1pRyc2Rt2yha5my4NNIEpBOlX3ZjD8=]G0704 Spindle Bearing Replacement - YouTube

Hoss

[Alistair Spence]

I worked with Michael in changing his spindle bearings starting here and it shows a couple wrenches
that can be made to help with removal.
http://www.cnczone.com/forums/bencht..._my_x2-20.html
Pics below of the upper spanner wrench I made.
These couple videos show how to remove the spindle and intermediate gears.


Hoss

That's very helpful.

Thank you.

Alistair.