Grizzly 4003G Lathe Chatter Problem

Today I pulled everything off the lathe, the compound, cross feed, carriage, pulled the spindle out again, removed the motor, and completely re-leveled the lathe with rubber feet. I did a deep cleaning of the compound, cross feed, and carriage. When the motor is running all by itself it is quiet and vibrates very little. I remounted it with rubber spacers between it and the machine. I checked every gear in the gearbox and on the spindle, all in good condition. Unfortunately I don't have a proper setup to really get a super accurate reading by sweeping the spindle, but from what I can do, it did not appear bent. The bearings and races were still in pristine condition. All the bed is crack free, as are the compound, cross feed, and carriage.

Everything went back together without a problem but the issue remains.

I was on the phone with Grizzly tech support who were, as always very friendly and willing to help. Unfortunately after an hour or so there was no progress. I was told that they would get back to me tomorrow after they had some more time brainstorm and to look over the photos that I sent in.

I must be missing something....right?! Maybe? Well my buddy has the same lathe as I do, So maybe I'll give him a call and go do some comparisons...He is only a 5 minute drive from me.
 
I would say you are missing something and it's not in the orig scrap job. Things dont go from nuts tight to shaky for no reason. Something has had to have changed. Even a part wearing normally dont go from ok to crap over night. It normally shows as it wears and gets worse as it wears.

I'm just not sure what your missing. It seems it's been asked and checked already for any idea I might have.

But from a mech back ground, i would look for bearings, bushings, and cracks. It seems something round is no longer round. I will ask our instructor tonight if maybe he has any idea's.
 
About the only thing that's not been discussed is tooling, box of bad inserts? Chip stuck in the tool under the insert? I'm grasping at straws.
 
Got ahold of Grizzly Tech support again, was told they still hadn't gotten around to looking further into my picture and problem...I'm getting a tinsy-weensy frustrated with them by now. As I did contact them and send in the pictures on friday. Oh well, all good things come in time?

Anywho...All my bit's are brand-spanking new. I used a new side of one each time I tried something new. All the tooling was double and triple checked for proper functionality and it's all in good shape. Once I had a bit that was super loose in it's tool because the retaining screw threaded itself out, Its worth noting that even that gave me superior results to what I'm getting now.

As mentioned, my buddy has the same lathe and he has also had it a year longer than I, he had some thread chatter issues when he first got it, but that was due to a loose leadscrew. Besides that, nothing is different, at least from what I can tell.

Hopefully Grizzly calls me and says "A replacement is on the way!" Wouldn't that be a perfect world? I'm trying to imagine returning my current one though, the extent of my returns is small boxes from amazon, I can't exactly walk into UPS and ask for a box and some packing peanuts for my lathe.... "Just toss her up on that there scale!"
 
I don't know if Grizzly offers service contracts but that is about the only thing that would partially help in this case. Most machines are warrantied to cover exchange of defective parts. Warranties do not cover labor to diagnose or perform the repairs -as that is the purpose of a service contract which are usually underwritten similar to insurance policies. Your machine is well beyond the "premature mortality" period and in this case, it may have been the parting blade incident that triggered something to go wrong. Even service contracts won't fully cover damage caused by metal-hitting-metal but rather, you'll get a discount on the hourly labor fee. In a situation like this, I would not expect the dealer to suddenly offer-up a lifetime satisfaction guarantee. In your shoes, I would check if your homeowner insurance policy will cover this. For my business alone, I have three kinds of insurance policies -and one them covers accidental damage to the machines...


Ray
 
James here's another idea, you could use a dial indicator to touch various components while its chattering to see if the needles flutters, probably start at the compound, then cross slide, then saddle, carriage, probe around the machine, at the slowest speed even the chuck, be safe don't take a dial indicator to the face. Maybe you can find what's loose and vibrating under load.
 
Have you checked your tool post since the parting tool incident? The piston/wedge mechanism, or some other feature of the tool post, could have been distorted and is no longer clamping the tool holder securely. Or it could be clamping the tool holder such that cutting tool clearances are affected.

Tom S.
 
Just had a thought. Back in the old timey days, mid 90's, we used a vibration meter to diagnose automobile vibrations. It would display the frequency of the vibration and we could use that to determine if it was at the speed of the wheel, driveshaft, engine or ? I wonder if something like that is available and useful in this case. Do you know any mechanics at dealerships you could ask if they have this type meter?
Dave
 
So I was thinking that I could borrow my friend's toolpost from his machine to see if that was indeed the problem, then I realized that I could just borrow his whole carriage! Hehe...this is the best idea I've had in weeks! I would assume that If I swapped out my entire carriage with his and the problem continues then I would be able to factor out my entire carriage as a problem? Maybe? Then maybe I can convince him to let me borrow his spindle...just for a bit...:whistle:

Anywho, this makes me wonder if I could just swap parts until I find the culprit. That is until I mess his machine up!

I think I'll swap the toolpost first, then move onto dial indicating everything for vibration...then maybe get into that black magic that your mentioning Dave!

Ray, I had no idea that homeowners insurance covered things of that nature. Perhaps I'll look into that, Although I vaguely remember seeing that our homeowners insurance covers event that occur within a certain area. I'm not sure of what this area is, but my shop is 100 or so feet away from our house.

Regardless, I'm out of town until Friday afternoon so hopefully I'll have a rekindled spirit for more trouble-shooting by that time.

Enjoy your evening folks!
 
I was able to swap out my toolpost and entire carriage with my friends. The problem persists.

Another one of my friends works for a fab shop where they need a roughing machine. I told him about mine and he is pretty sure his boss will buy it. I know him and he's willing to give me more than a fair price for it. So It looks like this bad boy will be going away from my shop and to another home within the next week or so. It's really too bad that I was never able to pinpoint the problem, and I'm certainly not a big fan of giving up on things. But at this point in time I feel beat down by my own machine, And It may win before it goes out my door.

But with this farewell, there is a hello on the way...one that is beautifully blue, and has a larger bore on it. Stay tunes for that!

Since my production has come to somewhat of a standstill, I decided it was time to clean and rearrange my entire shop. This included giving my center island a nice white coat of paint and putting up some more shelves. Oh, and coolidge, if you look real close you can see some of that real special wiring that I'm so fond of in my shop :whistle: That will also be getting ratified in my lathe-limbo.

image.jpeg

Anywho, The girlfriend is opening her food truck on wednesday, so fancy and delicious food was in order for tonight.

image-1.jpeg

I'll post any new updates for the lathe, if there are any to come.

image-1.jpeg image.jpeg
 
You must log in or register to reply here.
Back
Top