Lead Screw Issues

I have my printer up and running (thanks to all those who already gave advice.) I have even managed a few successful prints. I am having a problem with my lead screws though. The one on the right of the machine (closest to the electronics) makes a really loud high pitch noise when moving from the top to the bottom (i.e. towards the bed), going up the noise is there but considerably less. I thought it would just be in need of oil, oiled the screws and no change. Is there something else I should look for?

Try adjusting the current for that motor on the stepper driver

Don't adjust the motor current. It is set correctly when shipped.

Possibly this is caused by the nut not bearing any weight on that side due to the Z bars not being exactly vertical. Try loosening the bar clamps and sliding them to the right.

---

[www.hydraraptor.blogspot.com]

So take the z axis bar clamp (the one at the top of the gantry, loosen it and move it towards the right some? (Just trying to make sure I understand you correctly.)

Yes loosen both left and right, with the axis at the top and see if you can slide it right so the X axis sits on both nuts when it is parallel to the bed.

---

[www.hydraraptor.blogspot.com]

Okay, that is definitely the problem. But doing the above procedures doesn't help. I spent all morning fiddling with this and no amount of adjusting will get rid of the high pitched noise.

Here is what I know from playing all morning:

-if I push up with any amount of pressure on the x motor assembly as it is traversing down the lead screws the sound disappears, really just the slightest of pressure corrects this problem.
-I can get the sound to disappear by adjusting the lead screws, but in order to get the sound to disappear it ends up very unlevel, i can level it but if it is level there is no way to get rid of the sound doing as you suggest above.
-so than i though that maybe the bed isn't level (relative to the frame thus causing the problem), but no go the bed is perfectly level relative to the frame
-however when I do level the z axis against the bed and home the z axis i noticed that the lead screws protrude differently at the top. that is on the left side there 3 threads showing, but on the left only 1
-the brass nuts on both sides are firmly seated into the assemblies
-for what its worth the lead screws are not straight, i.e. the right one has a not noticeable to the naked eye, but a measureable bend to it
-if i push on the right lead screw slightly pushing it towards the gantry it stops the noise as well

A couple of questions:
-is there another solution here?
-is it damaging to the machine to have that high pitched noise?

I think I could make the bed not level to the frame, by placing an extra washer underneath the bed to raise up the left side, making it possible to raise up the left Z axis (the one with the idler) and still make the bed level with respect to the extruder . . .

Other than that I am really at a loss as what I could try

Edited 3 time(s). Last edit at 01/26/2014 01:39PM by academicdave.

Okay, update. As a crazy idea, i took out the lead screws, flipped them. And now it works. . . . . no idea why this worked but it did. Only a very small amount of noise at the very top, currently.

Add weight (up to ~200 gram) to the left X-idler-bracket. It solves all the problems.

Edited 1 time(s). Last edit at 02/25/2014 08:25AM by karabas.