'Z' doesn't sound good

[nosplinters]

Howdy all,

I recently got my Taig 2019 setup and I noticed when I move the 'Z' downward (-) it makes some funny vibrating sounds. It's nice and quiet moving upward (+). Sometimes the 'X' does the same thing when moving to the right.

Any ideas what would cause this (alignment, lube, stars misaligned, etc)?

Another question I have is in regards to lube. I don't know of any industrial supply shop around here; therefore, I picked up some automatic transmission fluid at Schucks. I haven't put any on the machine yet. I wanted to get some opinions first. I almost bought some synthetic gear oil that was pretty thick and spendy to boot. I'm thinking I should have probably bought that instead of the quart of ATF.

Let me know what you all think.

Thanks
-Ed

[jalessi]

ATF is a good choice.

Synthetic gear oil is much to thick in viscosity, in the cold it will have big problems!


Jeff Alessi
jalessi@aol.com

[jalessi]

What stepping ratio are you using?

[nosplinters]

Great, I'll stick with the ATF for now.

The stepping ratio is actually another question I posted on the Xylotex group forum.

I was thinking that could be a problem as well.

I currently have 269oz steppers being run from the Xylotex board. I'm using Mach3; however, when I set things up I grabbed someones pre-configured Mach3 motor tuning setup. I noticed that the Revs Per is set at 32000, which seems very high to me; however, I have no idea how to figure out what the values should be.

Sorry I can't be of more help here.

Thanks

[jalessi]

Ed,

The vendor that you purchased your system from should be able to tell you the correct settings for your (steps per) stepping ratio.

The higher the steping ratio the smoother the machine will run however it might lose torque if set to high.

Also you can slow down the velocity and the acceleration, just make sure you document the settings you started with.

I also want to mention that if your stepper motors are not aligned on the mill correctly they can bind the drive screws.

Did you check for any binding?

Jeff...

[nosplinters]

Hi Jeff,

I checked for binding of the stepper on the 'Z'. Didn't find anything. I played around with the gibbs as well, still nothing. I also lubed it up.

I maybe imagining things. It could just be resonance coming through. I've never heard a CNC in action before; therefore, I could just be picky.

Thanks
-Ed

[under-dog]

I had the same thing when I first got mine. Kind of a wuh wuh wuh sound when the head is lowered. I adjusted and adjusted the gibs to no end and could minimize but not get rid of it. Then one day after my feet were sufficiently wet. I decided to make sure my entire machine was "tight and tuned"


This is when I discovered this:

The plates (L&R) that hold the mill head assmbly to the Z slide were not snugged up. The whole assembly could rock foreward and backward on the Z slide.
The cure:
1)I gently(so as to not damage anything) clamped the mill head assembly to the slide.
2) loosened up the two plates on either side and pulled them in snug and retighted the socket head cap screws.

I attached some jpegs to demonstrate.

I woulds see if there is play in your head there as well. Grab the whole assembly and see if it rocks. I would go through the exercise anyway.
Once I tightened it up it is real smooth now.


The taig is really nice but a few things need to be tightened and adjusted. Whether it loosens up from shipping or they just leave some tweaking to the customer. Nothing major though like some imports you hear about with people cleaning casting sand out, lapping all the ways and replacing a whole bunch of parts, etc.


Hope this helps and is the answer to you issue. I know it plagued me for about a year. It drove me nuts and I thought I would have to live with it, But once I really felt comfortable around the machine and started to tweak things I was like "duh" that was so simple.

Let me know how you make out

[Stepper Monkey]

Steps per inch don't sound like a problem. With 1/8 microstepping on a standard 200 step motor and a Taig screw that would be correct.
8 x 200 = 1600 (steps per rev) 1600 x 20 (tpi of screw)= 32000 steps/per inch travel.

Where you really need to look in Mach is the acceleration curve of the Z, which should not be anywhere near as high as the X and Y can handle. That is of course if the settings are really the problem and not simply an adjustment issue.
The only really weak part of the Taig design is that heavy AC motor is cantilevered out so far forward - and worse yet off to one side as well - that it makes adjusting the carriage to travel without binding a troublesome task at best.
This is one reason I went to a DC motor on mine. Speed control was a nice gain, but the lighter weight of a similarly powered DC motor helps Z travel speed and smoothness a lot, as does the ability to place the motor further inboard and closer to centerline to prevent binding.

[under-dog]

Originally Posted by nosplinters Great, I'll stick with the ATF for now. The stepping ratio is actually another question I posted on the Xylotex group forum. I was thinking that could be a problem as well. I currently have 269oz steppers being run from the Xylotex board. I'm using Mach3; however, when I set things up I grabbed someones pre-configured Mach3 motor tuning setup. I noticed that the Revs Per is set at 32000, which seems very high to me; however, I have no idea how to figure out what the values should be. Sorry I can't be of more help here. Thanks

Do yourself a favor and download the Mach manual. It has instructions on how to do this.

[nosplinters]

Thanks for the detailed info Under-dog. While looking at the Z stepper, I noticed the forward and backward sloppyness on the head. I'll try your clamping method and see if the problem goes away.

Stepper-monkey, thanks for the info on the settings as well. I was thinking about going with a DC motor and utilize the speed control feature as well. Where did you purchase yours from?

-Ed

[nosplinters]

Ok, that was in fact the problem with the 'Z' rumbling. I had to make muliple adjustments, but it's nice and smooth now.

Of course, now my 'X' is making the same noise when it's heading to the right side. I don't see any real adjustments here. Any ideas on this one?

If I hit this problem in the 'Y' is there something to adjust there as well?

Too bad Taig doesn't send a nice little manual with their machines and a troubleshooting guide.

Thanks
-Ed

[jalessi]

Ed,

At 3:30 A.M. in Chicago, its funny how a new toy can keep you awake all night.

I dont know the answer to your X or Y axis questions however we should start a night owl forum.


Jeff Alessi
jalessi@aol.com