LumberJocks

New Jet Lathe - Grinding/Clicking Noise

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by builtinbkyn posted 04-22-2017 02:23 PM 1066 views 0 times favorited 47 replies Add to Favorites Watch
View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


04-22-2017 02:23 PM

So yesterday I finally fired up my new Jet 1221. With nothing mounted but the faceplate, I expected to hear a cool whirl and humming sound. Unfortunately that wasn’t the case. There was a noticeable grinding noise accompanied by an intermittent clicking or knocking. The machine on slow speed ran silently until the speed was increased.

So with some tools in hand I went about trouble shooting it myself. Removed the faceplate and live center, thinking maybe one of them were not seated right. Then I pulled the handled. Still the same noises. I then moved the belt to another speed setting and still the same. To my ear, it sounds like bad bearings.

Next step was a call to Jet. The tech, after hearing the noise thru the phone, had me go thru the same paces I had already done as the noise wasn’t usual. He then had me pull the belt and run just the motor. No noise was heard. He also had me loosen and tighten the set screws on the pulley in specific order- keyway first followed by the opposite side. Still the noise persisted. He informed me that since I purchased the lathe thru Amazon I would have to deal with them if this was in the first 30 days. However he did tell me that once a second call was placed, they would deal with it. That made me feel a bit more confident Jet wouldn’t just make the claim that since it’s spinning true and working, the noise is incidental.

I’m pretty confident a bearing or even both bearings are the culprit. I pulled the shaft and even though they don’t make the grinding noise when spun by hand, the belt tension could surely influence this situation if the bearings were faulty.

This is a pretty basic design. Nothing complicated about it. What I’d like to do is replace the bearings with higher quality bearings rather than wait the 30 days and then make the second call to Jet. I know it’s additional expense, but it’s also my time and heck, if the bearings they’re using aren’t all that great – I believe they’re NSK – sizes are 20×42x12 -NSK #6004vv and 25×47x12 – NSK #6005vv. Not being familiar with bearings, is there a better type of sealed bearing for this? Cylindrical bearings vs the ballbearings used? I suspect Jet went middle of the road and would actually prefer better if available.

-- Bill, Yo!......in Brooklyn & Steel City :)


47 replies so far

View GR8HUNTER's profile

GR8HUNTER

2951 posts in 546 days


#1 posted 04-22-2017 02:38 PM

I have always liked timken

https://www.timken.com/products/timken-engineered-bearings/

-- Tony Reinholds,Pa. REMEMBER TO ALWAYS HAVE FUN

View MrUnix's profile (online now)

MrUnix

5978 posts in 2032 days


#2 posted 04-22-2017 02:55 PM

Those are pretty standard radial deep groove ball bearings… If you really want to replace them, give Lynne a call at Accurate and she will hook you up. Although, NSK are generally pretty good bearings, and it would be very unusual to have new ones that were bad. If they are sealed (not shielded), it’s pretty easy to remove the seal and inspect the balls, cage and condition of the grease to see if they are good (you can’t tell just by spinning them).

I personally would let Amazon/Jet fix the problem since it’s a new machine.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View Hockey's profile

Hockey

90 posts in 246 days


#3 posted 04-22-2017 03:00 PM

If Amazon exchanges it for a new one with shipping at their expense, I would go that route. Don’t know if they do that on lathes.

View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


#4 posted 04-22-2017 03:22 PM

Thanks for the responses guys. I guess I may first try to deal with Amazon on this and see if they’ll replace it. Packing this up and getting it shipped will be a hassle, but may be the route I should go. I guess I’ll base my decision on the logistics – hopefully Amazon will provide a pickup vs me having to take it to a shipping center. I hope I don’t get another with the same issue. Actually regarding the issue, am I expecting too much? I thought it would run pretty silently except some noise from the belt.

-- Bill, Yo!......in Brooklyn & Steel City :)

View Rick_M's profile

Rick_M

10606 posts in 2214 days


#5 posted 04-23-2017 01:33 AM

Amazon has fantastic customer service. When I returned a lathe they gave me a shipping label and arranged for UPS to pick up the box. But I had to buy a 2nd lathe and wait for a refund on the first lathe when they received it in Kentucky. If you bought from CPO through Amazon, CPO will ship a replacement as soon as they get confirmation by UPS that you shipped the bad one but you’ll need to call them to make that happen.

As for bearings, NSK is a premium bearing. It’s weird that you got bad bearings in a new lathe. This wasn’t a warehouse deal by any chance?

-- http://thewoodknack.blogspot.com/

View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


#6 posted 04-23-2017 04:45 AM



Amazon has fantastic customer service. When I returned a lathe they gave me a shipping label and arranged for UPS to pick up the box. But I had to buy a 2nd lathe and wait for a refund on the first lathe when they received it in Kentucky. If you bought from CPO through Amazon, CPO will ship a replacement as soon as they get confirmation by UPS that you shipped the bad one but you ll need to call them to make that happen.

As for bearings, NSK is a premium bearing. It s weird that you got bad bearings in a new lathe. This wasn t a warehouse deal by any chance?

- Rick M

Hey Rick. The lathe was sold and shipped by Amazon according to the description on my order. I don’t know. Maybe I’m expecting the machine to run differently than it’s capable of. It turns true, but I didn’t expect it to sound the way it does. The tech even commented it shouldn’t sound as it does when hearing it thru a cell phone. If it’s the bearings, I can replace them easier than shipping the darn thing back and then waiting on a replacement. There’s no issue with the motor and everything else is fine. The electronics work and the speed readout seems to be accurate for the pulley setting. A bearing change is the easiest route. They’re $15 each. At this point I’ll wait the 30 days and then see what Jet has to say. In the meantime I’ll use it as the tech said I should do. If there’s any significant issues, they will reveal themselves during use.

-- Bill, Yo!......in Brooklyn & Steel City :)

View MrUnix's profile (online now)

MrUnix

5978 posts in 2032 days


#7 posted 04-23-2017 04:46 AM

They’re $15 each.

Someone saw you coming :)

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


#8 posted 04-23-2017 04:48 AM

Well that’s on the cheap side on bearingsdirect.com or something like that. Amazon has them for $25 each LOL Maybe I’ll call your friend ;)

They’re $15 each.

Someone saw you coming :)

Cheers,
Brad

- MrUnix


-- Bill, Yo!......in Brooklyn & Steel City :)

View Rick_M's profile

Rick_M

10606 posts in 2214 days


#9 posted 04-23-2017 06:08 AM

$15 is nothing for quality bearings. I would be suspicious if they were less, especially something uncommon like VV.

-- http://thewoodknack.blogspot.com/

View MrUnix's profile (online now)

MrUnix

5978 posts in 2032 days


#10 posted 04-23-2017 06:22 AM

$15 is nothing for quality bearings. I would be suspicious if they were less, especially something uncommon like VV.
- Rick M

6000 series = Extra light duty metric
VV = double non-contact seal (one each side)

Nothing really uncommon about them.

Cheers,
Brad

PS: The ‘non-contact’ seals are really unnecessary IMO, given the low speed of a lathe. The max speed for the VV’s is ~20,000rpm, the contact seals (2RS) are a few thousand less. The max spindle speed of that Jet lathe is 3,600rpm :)

-- Brad in FL - In Dog I trust... everything else is questionable

View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


#11 posted 04-23-2017 01:46 PM

Yeah I did see similarly spec’d bearings for about a 3rd of the price. I was actually interested in getting better bearings than the OEM bearings. I was wondering if they need to be deep groove bearings or if cylindrical bearings were suitable. Aren’t they supposed to be better? I have no knowledge of this :)

-- Bill, Yo!......in Brooklyn & Steel City :)

View MrUnix's profile (online now)

MrUnix

5978 posts in 2032 days


#12 posted 04-23-2017 06:37 PM

IMO, you should just go with what it was designed with… cylindrical roller bearings are designed for radial loads, not axial. The deep groove bearings that were in there are designed to handle both radial and axial loads.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View builtinbkyn's profile

builtinbkyn

1921 posts in 774 days


#13 posted 04-23-2017 07:23 PM

OK thanks Brad. One thing I’m going to do before anything else is to pull the shaft, remove the bearings and inspect them and the recess each seat. The casting may have some flash or something that’s preventing one of them from seating properly. My suspicion would be the one on the work side. The retainer for that bearing is a metal flange that bolts to the housing. If the bearing isn’t seating all the way in or of it’s skewed somewhat, it could be causing the sound I’m hearing. The motor without the load of the tensioned belt, spins silently. I don’t suspect the motor in any way. It has to be something else.

The other thing that could be causing this is the collar for the speed sensor. It’s rather poorly executed. It’s a machined aluminum collar that slides over the shaft and is retained with one set screw. Inside the collar is a magnet that’s retained with a c-clip. It has a shoulder on only one side to bear on the shaft. The other side, where the magnet is retained with the c-clip, has no support on the shaft – if that makes sense. I checked to ensure it wasn’t hitting the pulley housing and it wasn’t. However now that I think about it, it could still be the culprit. Centrifugal force could actually be causing the magnet spin inside the aluminum collar. That would sound like a bad bearing. An easy fix would be some CA glue inside between the magnet and the collar.

-- Bill, Yo!......in Brooklyn & Steel City :)

View Rick_M's profile

Rick_M

10606 posts in 2214 days


#14 posted 04-23-2017 09:13 PM

This is the kind of stuff I do to old lathes, I sure as hell would never accept a new lathe that needed that much work without a significant discount.

-- http://thewoodknack.blogspot.com/

View MrUnix's profile (online now)

MrUnix

5978 posts in 2032 days


#15 posted 04-23-2017 09:57 PM

This is the kind of stuff I do to old lathes, I sure as hell would never accept a new lathe that needed that much work without a significant discount.
- Rick M

+1

If you were willing to do the work, you could have saved a significant amount of money buying used. Given that it’s new and never been used, have them make it right. You have waited this long before ever getting a lathe, so a few more days isn’t going to kill you :)

Sort of related – My PM45 has a slight clicking/clanking noise at certain speeds. Turns out the index wheel has loosened up where the cutout for the keyway is, which is letting it move around a bit – and is apparently the one common problem those lathes have. I have just ignored it, as it doesn’t effect the operation of the machine in the least. But I have a new drive belt on order, as the one on there now is showing it’s age and has a couple of ‘cogs’ that have gone missing. I plan on welding it to the stop collar that sits behind it when I go to replace the belt, since I will have to pull the spindle anyway. Stuff like that can be expected on a machine that is over 30 years old… but I would have been pretty upset had it been a brand new one that I paid top dollar for!

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

showing 1 through 15 of 47 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com