[hayes]

OK, so the spindle finally died on this old machine. Ran it up to 6k rpm and the motor stalls out after about 20 seconds of running. Tried again at 4k, same thing. When I try to manually turn the spindle it's difficult at best to turn by hand.

I'm trying to pull the spindle out and just won't come out. I've unscrewed the bolts on the bottom ring face, the set screw on the side, pulled the snap rings off the top and this thing just doesn't want to come out... is there a trick? Has anyone else replaced one? Did a search on here and wasn't able to find anything. I'm up a creek and was right in the middle of my first production run on these parts.

Novakon John, will the new spindle cartridge fit in these old NM200 heads?

Thanks,
Josh

[SCzEngrgGroup]

REMOVE the spindle motor, then remove the four bolts from the bottom of the spindle cartridge. If the spindle doesn't slide out, tap it out with a dead-blow mallet. The cartridge WILL come out. You can test the motor with the spindle removed. If the spindle is hard to turn, you need to determine whether it is the motor or spindle causing the friction. Both should turn VERY smoothly and freely. If they don't, then it is certainly a bearing problem.

Regards,
Ray L.

[hayes]

Thanks Ray, I had already removed the motor and the motor mount, top bearings, etc. Motor spun freely and smooth. I finally got it out, and it took some convincing with a hammer. It's not a cartridge unit, but the older style spindle assembly. It was most definitely the bearings that had failed, and as one of the bearing races remained in the head, all the balls came flying out. Not a pretty sight. Definitely looking at what I can do for an upgrade at this point.

[Novakon]

Hello Josh,

I have attached the two variants of the spindle which, should be the one you have, and the newest spindle cartridge assembly. I believe the new spindle cartridge is directly compatible with the older mills but I will have to verify this for certain. If you need to discus this more in detail, please send me an email at [email protected].

Regards,
John

[hayes]

Hi John,
Thanks for the response, I just sent you an email. It is definitely the older spindle style, but the body of the spindle is 80mm, so the new cartridge should fit. Hopefully you have these and the other necessary bits in stock.

Thanks,
Josh

[hayes]

Thanks to Novakon and another user here (thank you!) I have a new spindle in place and working so much more smoothly.

One thing I have noticed though is that the new belt is a good bit louder. Is there some tuning I need to do on the belt tension? Right now it has about 1/8" - 1/4" play in it. Does it need to be more, or less like an automotive accessory belt? Has anyone found any belts that are quieter? I'd like to not have to wear ear protection while I'm out in the shop with the machine working away.

[Novakon]

Hi Josh,

The belt tension sounds about right. Do you have the Aluminum or the steel pulleys? The Aluminum pulleys are currently supplied and are of a much better quality. There were some older steel pulley that were not perfectly centered and had contributed to some minor noise issues, this is why we switched to the new Aluminum pulleys. There may be one other factor that comes to mind. If the motor mounting plate is slightly not perpendicular with the spindle center line, the belt will crowd to one side and can become noisy. You should be able to see this crowding condition with the side plates removed while it is running. Try shimming the front (or back) side of the motor to see if the noise lessons. thick washers under the frame bolts will work well for the test. The sound should be just be a "low level" sound and you should not need ear protectors. Noise like this will reduce the life of the belt and should be looked into.

Regards,
John

[hayes]

Hi John,
Both pulleys are the aluminum units, so I'm ok there. At 1000rpm, it's quiet, at 2000rpm it's about the noise level of a conversation, at 3000rpm it starts getting loud and at 4000rpm I have to cover my ears. Granted the side plates are off the head at the moment, but the noise level is higher than I expected. I don't see any crowding of the belt on the pulley side plates, but I will try shimming the motor and see if I can get things to quiet down.

I had two other thoughts... I'll try running the motor without the belt to ensure it isn't the motor bearings. My second thought is to try flipping the belt, but I don't think these are uni-directional belts.

[LeeWay]

Is it a timing belt or V belt?
If it is a Vbelt, do yourself a favor and go with link belts. I have them on almost everything we have that is driven by Vbelts. Incredibly quiet. Almost stalker quiet. Plus, just keep some in stock and you have a belt replacement for everything.
Grizzly T21992 Power Twist V-Belt, 1/2-Inch x 4-Foot - Link Belt - Amazon.com

Vibration Free Link Belt

[hayes]

As far as I know all the NM200 / Torus / Torus Pro machines all use a cogged timing belt setup. Stalker quiet would be fantastic, but I don't know if we'll be able to pull that off with a timing belt setup.

[SCzEngrgGroup]

The stock setup on the Torus Pro is pretty quiet, even at max RPM. If it's making objectionable noise, there is something wrong - either belt, pulleys, or alignment. The only way to resolve it is by swapping out parts and testing. Having the side covers off will significantly increase the noise level. Also, a new belt will take a few days, or weeks, of use to fully wear in and quiet down. It WILL be louder at first. But the kind of uncomfortably loud noise you describe indicates a pretty serious problem somewhere.

Regards,
Ray L.

[LeeWay]

I have timing belt spindles on the Pulsar (4500 rpm) and the older 80/20 mill with the X2 head. 6600 RPM. Had it on the Torus as well. 4500 RPM. They are relatively quiet. I can hear the old mill spindle bearings starting to go bad when it gets louder. It shows there and in the cut. It breaks smaller end mills quicker when the bearings start to go. When I used it for production, I replaced the spindle bearings every year. X2 heads are not meant for production.
Timing belts should be relatively quiet. I agree with Ray. Something else must be wrong, however install those side covers first just to check with your memory of how it sounded before.

[engnerdan]

Hayes,
If you have the 6000 RPM motor it could be bearings or rotor balance. The first one I had was about twice as noisy as the second one I have now. There was something with the rotor of my first motor.

Check the concentrically of the motor shaft, pulley, spindle pulley.

-Dan

[hayes]

Well, I played around with it yesterday and found two things. One, the belts are uni-directional, meaning there is a right way to install them and an upside down way... I had the belt installed upside down, so the teeth were not engaging the pulleys correctly. I flipped the belt right way around (text on the belt is right side up) and adjusted the tension slightly and it's nice and quiet now. With the side plates on and running the spindle at 6K rpm I can now have a conversation with someone and not wear ear protection. The loudest component now is the motor fan.

[SCzEngrgGroup]

Well, I played around with it yesterday and found two things. One, the belts are uni-directional, meaning there is a right way to install them and an upside down way... I had the belt installed upside down, so the teeth were not engaging the pulleys correctly. I flipped the belt right way around (text on the belt is right side up) and adjusted the tension slightly and it's nice and quiet now. With the side plates on and running the spindle at 6K rpm I can now have a conversation with someone and not wear ear protection. The loudest component now is the motor fan.

I find that VERY hard to believe.... If the belt appears uni-directional, then it is badly worn, and should be replaced.

Regards,
Ray L.

[hayes]

It's a brand new belt, and considering it is a timing belt profile (and coming from a professional auto engineering background) it's not improbable at all. It is uni-directional for installation only, meaning there is a correct installation direction (text right side up) and an in-correct installation (text upside down). Rotationally, the belt can move in forward and reverse directions without issue when it is installed correctly.

[kvom]

I have never seen a toothed belt that was asymmetric, but there's a first time for everything.

As for noise, I wonder if the Torus is quieter than the NM200. It seems to be that the best way to determine if something is wrong would be if the sound changes significantly. Maybe John can diagnose mill noise over the phone.