I’ve had my 1100MX almost two years now, but only this year started getting work, and only these past ~3 months working any more than 8 hours a week. These past three weeks i’ve put in around 30 hours per week. Mostly Delrin/Aluminum with a lot of weird 3D contours that require adaptive clearing, scalping and blending. And some rigid tapping, M4,5,6,8,10,12 if that matters at all.
I always make sure to pull the oiling lever no less than once every 2 hours, lately, once every hour to be safe.
Just today, my Z-axis has started vibrating during high-speed or rapid moves. At 180ipm, it literally shakes the machine, emits a very low frequency noise, and you can feel it in the concrete floor. No vibration or sound at all around 20ipm during machining.
The noise frequency is so low, my cellphone camera can’t hear it at all. Tried multiple ways to get a video, and on playback, can’t hear the vibration at all.
What would be the troubleshooting steps for this?
Any help or advice would be greatly appreciated.
I get this when (I think) something gets onto the lead screw and then rides around on the bearing. I usually wind the z all the way down and oil the lead screw manually then blow it off and see if it fixes it. If not I go again. That has fixed it a couple times. Also once I had this happen and a reboot fixed it after the above didn’t resolve it.
Got a ladder out and climbed up the back of the machine and found a ton of aluminum chips hanging out up there. Probably need to be more careful about cleaning the vise with the air gun.
Concerningly though, i also found that the ways were pretty freaking dry… this cheap little hand pump that came with the machine doesn’t seem to cut it.
I had originally considered buying the automatic oiler when I bought the machine, but it’s a “dumb” oiler in the sense that it doesn’t know if the machine is actively running, or just sitting online overnight. It would continue pumping oil all night long while I’m sleeping. I found that if I turn the machine off overnight, then I have to completely re-zero my tool setter, tooling, etc, to get within 1thou on critical tolerances. Huge waste of time i.e. money.
I check to make sure the refrence bumpers (the metal things that hit the switches when you refrence machine) are tight regularly. On mine the x is loose after a couple weeks, but I power my machine every day.
The ways are tricky. They only need a tiny amount of oil. More oil attracts more junk to stick to it which makes it grind and turn into grease and then it attracts more junk. Less is ideal as it stays cleaner and then doesn’t attract as much chips and then doesn’t grind and need more oil to clear the sludge. Obviously there are reasons to use more oil but as long as there is a tiny bit and no metal grinding it should be fine. I pull my oiler once a day when i refrence and do a lap on all the axis. Once every 2 hours is probably a waste of oil, but it’s not going to hurt either. I hate filling my oiler though.
So, I wanted to come back and give an update to this topic after a couple more weeks of machining. it seems like the machine really does not like being left on overnight. as this issue appears to be some kind of noise or glitch in the stepper driver, so after leaving the machine on overnight or for a day or two, it does this weird vibrating thing, and unfortunately, power cycling the machine seems to be the only way to fully resolve the issue. which is a huge waste of time to run the ATC to re-zero all 12 tools every morning. oh well. it is what it is, i guess.
You need to touch every tool in the ATC to get the lengths back? I’ve not run into that on my 1100MX. Once one is set the offset to the rest remain the same.
Yes, the offset tool-to-tool is the same, but offset to the probe changes every power cycle, as the hard-stop zeroing method is unreliable. I’ve seen worse than +/- 1thou repeatability, and yes, my hard stop is tight, and my probe is good. After a power cycle, re-zeroing the ETS to the spindle nose and then re-zeroing all the tools fixes this, and gets much better results.
Re-zeroing the spindle nose to the ETS is a must after a power cycle. As is setting your WCS zero. I agree that the hard stop homing method can be inconsistent. Mine usually moves less than .0005" on any given axis but occaisionally it goes beyond that. The only real solution to that situation is absolute encoders.
There’s no specific need to touch off all of your tools though. Those lengths are effectively set relative to the length of T0 (empty spindle) so if the machine knows where that is based on referencing your ETS, it knows where all of your other tools are by reference.
The only significant change to tool length (and by significant, I mean .001 at most) would be due to spindle temperature. I have definitely seen a change in tool length from a hot spindle to a cold one. But that has nothing to do with powering down the machine and everything to do with ambient temperature and machine idle time.
Yeah, that’s what I was thinking. I re-zero after power cycle, then re-set the WCS, so the tool offsets come along for the ride because they are set relative to that. I don’t do a lot of <.001" work and don’t have a lot of permanent fixtures so that might change the process.
I personally like my ways a ball nuts/screws a little sloppy wet with oil. Reduces stiction, helps control corrosion, which can kill a ball nut, and you can snug the gib up a little more. Yes, coolant suffers a little. I just wipe where I can.
Low frequency can also be the enclosure vibrating. It’s a bit like making a thunder sound with a sheet of metal. It can literally shake the whole building at the correct frequency but it’s all air pressure. Check your enclosure bolts. I recently had a weird whine on my x but only one direction. After some crazy vibration tests it seems to have been coming from the left front foot wearing off enough concrete to be off the ground only when jogging x- and y- at the same time which was making the enclosure shake.
There is an app for iPhone that has a very sensitive vibration sensing. It’s called “vibration sensor” and another called “sonic tools” they are both free and I use them a lot to try to figure things like this out. The vibrations sensor works best if you hold the phone in a vice or something secure but that’s up to you.
Bottom line is if your machines making noises not cutting check every bolt on it first. It’s never going to sound like day one. Hopefully it will sound better though as we learn as we go.
No, the oil system pushes oil into the ball nut assembly, if that is what you have. It fills the races with oil helping prevent debris from getting in and pushes debris out the seal end if it manages to get in. Plus debris will tend to drip off. Yes, it’s a constant battle. Dust is the worst. Chips, not so bad.
This particular issue for me, was definitely a servo-electric problem. As the last (3) times it started vibrating, power-cycling the machine immediately solved it.
Bruce is correct, Tormach tech support said you can’t over-oil the machine (discussing setting up an auto oiler timer),… and I spoke with the maintenance manager at my day job, where we make 100k+ automotive parts a day, and they err on the side of more lube, as the fresh clean lube pushes the dirt out of the moving parts. They also reclaim and send off the excess way oil for recycling.
Yeah, even industrial grade linear bearings and ball nuts need to be purged of crap. Company I used to work for machined aerospace composites. Brutal on the machine moving parts.
Same problem and solution here. Z axis vibrates the machine like a small seismic event. Power cycle and it’s better. I have been thinking of some kind of z screw guard that could ride on top of the axis to deflect some of the chips that pile I’m up there and ineveriably get into the screw and go through the bearing. Hey Tormach, what about a cone shaped or convex bumper on the top of the Z? Let gravity move some of those chips for us, increased ball screw life.
I’ll wait for some feedback before I try to figure out how to chamfer that upper bumper without removing it.
