Wear in spindle splines or pulley

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I have 2 Series2 R2e3's. I have noticed there is a noticeable amount of rattle from the spindle splines on both machines. How much is acceptable if any? What do you do if it needs repair?
Thank you for any info,
Cutmore

[bborb]

Wear in the keys on both moveable shivs (pulleys) can cause "rattle" in the head, your splines may be fine.
Just a thought.

[machintek]

That is the number 1 reason for head noise.
I have also seen the "clutch" teeth for high gear wear a bit and make noise. If I move the HI/LOW shift lever up past the pin hole and it quiets down, I know this needs adjustment.

George

[swarf_rat]

I just went through the whole top end on my R2C3 (same mechanically). The things that can rattle are the motor moving pulley, the spindle moving pulley, the high gear dog clutch, the back gear, and the splines. Obviously the back gear only in low, and the high speed clutch only in high.

Mine was a poster child for neglect, I ended up replacing every wearing part (and many that aren't supposed to) and it still only cost about $1200. 3 month's worth of Starbucks lattes. Not bad for a serious machine repair.

Don't let it go too long. Once the wearing parts wear out, it starts to eat the (normally) non-wearing parts, which are the more expensive ones. The major rebuild kit costs around $240 or so and includes pretty much all the bearings and wearing surfaces. I also replaced the motor shaft, new moving pulleys (not re-bushed) and the splined hub and belt hub (the two ends of the high speed dog clutch). Most of the parts came from Mataco, who were very helpful.

Everything in there is the same as the 2J head with a very few exceptions: the motor shaft is slightly different and has an additional circlip, the motor fixed pulley key is the same but no roll pin (just drive it out), and the splined hub is slightly different (but it looked like the 2J version would work). Hardinge has 2 of the splined hubs left, for some reason they haven't raised the price on them to their usual outrageous prices.

On mine the spines were contributing almost none of the noise. I think a lot from the worn out motor shaft and motor moving pulley bushing, and a lot from the high speed dog clutch. Unfortunately the latter, if not just an adjustment problem, can be cured only by replacing the two hubs. Many of the bearings in mine were pretty loose and rough.

The thing is really quite easy to work on. There is one special tool required, a long reach spanner to get to the bearing nut that is up in the speed change sleeve. I made one out of a 2" steel pipe nipple. It helps to have some bearing pullers and a small press, nothing takes more than about a ton to R&R.

Mine now has some belt whine, other than that it is "quiet as a church mouse".

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Thank you for the replies,
Looks like the best thing to do is go on a recon. mission to find the source of noise.
Swarfrat,
Thanks for the info on mataco,
Hope there is not to much wear in there.
Cutmore

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Well i dug in to the head last night/this morning. Looks like the keys are worn on both the motor side and the vari disc side. Also still seems to be a rattle in the spindle from the splines. I have not removed the gear yet as I had to get to work this morning.
Does anyone have a picture of 1 of the series 2 cnc heads disassembled? I found a good picture a while back before I got mine but did not save the link.
What is under there that may need to be replaced?
I am going to take the plunge while I am this far and replace the z-axis belt too as I can not get the 1/4" of looseness out by adjusting the servo.

Thanks for any help/info.
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[swarf_rat]

The thing that is rattling is probably not the splines, but rather the high speed clutch. Fixing that probably requires replacing both the spline hub and the pulley hub. Still pretty straight forward.

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Well, I tore everything apart.
While holding the bull gear I could rock the spindle in the spline hub.
So the spline hub was worn, the bull gear was also making some noise. I am going to replace them both and see what I end up with.
I replaced the z axis drive belt already. Whew! that wasn't so bad. I was nervous about that 1 but it was pretty straight forward. After the top was off I just un-bolted the motor and dropped it down, lifted the lower half of the drive off with the servo for the z still attached. Then I lowered the quill to ~ 2" from the bottom, removed the 4 bolts holding the top plate on, and used the knee to lift the spindle enough to replace the z belt. Everything is back together waiting for the new parts.
Any one know how to get the pulley off the z servo? Mine has a threaded plate that the set screws go through. It looks like a taperlock but I could not get it to budge and I was not about to tear it up.
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[swarf_rat]

The Z pulley on mine was the collet type (taperlock) with 4 socket cap heads. Came loose easily. But I found it was not necessary to remove it to do most anything.

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Swarf Rat,
Thanks for the reply, I do not have to take it off but I figured while I had everything else apart I was going to take the z servo off to lighten the load when I lifted the lower drive assy off. Plus I like to know I can get things apart later when things go bad.
My pulley has set screws not socket cap screws? The set screws were through the front plate pushing against what I would think would be the taper.
Any one else seen how 1 of these work? Or is it just stuck and I gave up too soon?
Thanks for any replies,
Cutmore

[bborb]

Are there any other empty threaded holes for "jack" screw(s) ?

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Thanks for the reply,
There are 3 threaded holes in the front plte that the set screws are in, and 3 through holes.
In the "taperlock" part which goes on the motor shaft, there are 3 threaded holes in line with the through holes but there were no capscrews in these?
Is there such a thing as a reverse taperlock? Or maybe this thing has just been together so long it has siamesed itself into 1 piece.
Cutmore