Jet 1221 Makes A Knocking Sound in Fwd

Signed-In Members Don't See This Ad
TonyL

TonyL

Member
Joined
Mar 9, 2014
Messages
9,068
Location
Georgia
Hi folks:

I shut my dust collect off while wet sanding and noticed that my lathe started making a light, repetitive knock sound when rotating forward (which was being hidden by the noise of the DC). It doesn't make this sound in reverse. I removed my center and it still makes the sound, but again, only in forward. It just started doing this today. I would think it make the sound in both directions. I don't anything rubbing, not smell anything burning. It doesn't effect its operation (at least for now).

It makes the sound at all speeds; just more frequently at the faster the rpms. Any ideas would be greatly appreciated. Owned it new since Mar. 14, made about 350 pens with it - nothing else.

Thanks!
 
Signed-In Members Don't See This Ad
JimB said:
It's unlikely but check the belt and make sure everything is clean and nothing sticking to belt or pulley.
Click to expand...

I was thinking the same thing. Make sure there's no junk in there. Prob not much though if you're using a dust collector.

Mine used to / occasionally makes what is refer to as a clicking sound in reverse. No bog deal though to me as it always want away.
 
Try taking the belt off the motor pulley and running the motor.

Also, rotate the spindle by hand without the motor/belt. Does it rotate smoothly? Place your ear on the headstock by the bearings while turning by hand.
You can use a mechanics stethoscope while it is running or use a screwdriver on the housing near the bearings with your ear on the handle end of the screwdriver. If there is any noise in the bearings, this will transfer it so you can pinpoint it. Check the motor too.

If you had a blank on the lathe at the time, check your live center too.
 
Tony...My first suggestion would be to call Jet C/S! It sounds rather odd that your lathe only makes the sound in fwd and not reverese, even at the same speed... Be sure and check all the screws that hold the drive spindle also as I noticed mine had become loose this past year (those that hold the cover over the bearings/shaft to the left of the faceplate shaft on the pulley housing...). Please keep us posted on what you find and Jet's recommendations/findings! Many 1221VS users out here on the web that want to keep abreast of issues with our lathe. Thanks in advance, good luck to you and safe turning always!!!
 
Thank you; I did plan to call Jet on Monday. Will remove belts and vacuum around.
 
Man before you go calling Jet do some investigating yourself. Maybe there is something laying against the lathe, take all chucks off and spin by hand. Take the belt off and run the motor. With the belt off spin the head stock. Check the chuck used. If using a live center check it also. Maybe something got lodged in the spindle, or somewhere else on the lathe.

If all is clear than call and maybe they have run into a basic problem and they can tell you what else to check. Run the knockout bar through the spindle. Good luck.
 
A loose set screw on the pulleys allows the pulley assembly to shift slightly and will make that noise -- easy to see if the pulleys move when you take the belt off the motor.

(mine was on a 1014 Jet)
 
Thanks Ken.

I did notice this morning that when I hand rotate the headstock wheel clockwise/forward/toward me, I can reproduce the knock-sound along one spot in the rotation. I will give Jet c/s a call in the morning.
 
Ok. Thanks to a fellow member and your collective advice, here is what I learned:

Set screws on the motor pulley were loose; so I tightened then (with the belt off)
Now, I did this even though there was no knocking sound when I ran the motor-pulley before I tightened the set screws.
Check the set screws on the upper pulley and they were tight, but I had the allen wrench out, so I snug them up - they didn't really budge.
Finding more set screws - this time on the black circular plate surrounding the drive center - I tightened them-up. One or two were loose.

I inspected the belt (off the pulleys) and can't say that I saw a flat or worn area, but I did see and two lighter black lines (dark great areas about an inch apart) on the belt.

The motor or the motor-pulley produces no clicking sound with the belt off, not with the set screws loose.

Placed the belt back on (two different sets of pulleys) and the clicking returned .
I thought this may have something with the belt and/or the pulley being under tension with the belt on - so I reduced the belt tension by one notch (second the the lowest/tightest), and the clicking stopped.

That is all I got :-). Turned a bolt action for a local police officer and it came out fine; lathe ran fine (but under the lesser tension setting).

Just keeping all posted, as some requested. Maybe the belt tension broadens what looks like the dark grey lines, and that is causing it, or simply the belt tension on the pulleys. I don't know, but will call Jet. Thanks all!
 
Spoke to Jet tech support this morning - a nice guy named Bobby.
He recommended that loosen all of the spindle (top) pulley set screws with the belt off of course, then tightened them. He also said, just don't tighten the loose one(s); loosen all, then tighten all. I didn't try it yet, but will tonight.

Thanks for your help; I hope it helps others.
 
If a belt sets for a while under tension, it will take a set, sometimes almost invisible. with the belt off, I know, you just got it back on, lay the belt on a flat surface and look for a bend where it does not belong. Easiest cure I know for this is to replace the belt. I have heard many good reports on the segmented belts but have yet to try them myself. Best of luck and keep us informed.

Charles
 
You must log in or register to reply here.
Back
Top Bottom