No way to level bed

[Mr.Hotwire]

So, this ever-evolving Pro-C debacle is getting more and more interesting.

So. Its printing now, Its running on Marlin 1.0.2, as 1.1.8 was giving me grief. That will come once I can ensure the hardware of the printer is working properly.. and this is where my problem with the impossible to level bed comes into play.

I can get all 4 corners to be level.. that is great. Move to the center of the bed... nope.. the nozzle is touching. I went about this for a few days thinking that I was JUST not doing something right. I could print, but the first layers were smooshed into the bed. Kept checking and checking.. No, give at all.

Checked my X-axis rods.. When I rotate them the carriage rocks up and down. The X-axis ends are parallel and square to each other, and it no longer rocks when I move in the Z axis, but it is not traveling in the X axis flat. there must be a dip, a bow, or something making it drop by at least the two sheets of paper I am using for the 4 corners.

The part that is getting me is... I can get the 4 corners to be right. even with traveling back and forth along the X axis.

Any hints? should I try to swap out my linear rods or even the bearings?

[William]

Hi, You can check if the hot bed is flat and then run the nozzle more than four corners. You can run it on all sides.

[Mr.Hotwire]

when i run it up the sides, its fine, when I move it along the front and back of the bed it hits the bed in the center.

[William]

Hi, first of all, you can put the hot bed on the horizontal table to see if it is uneven;
If the hot bed is flat, you need to adjust the height of the front and rear to achieve the consistency of the hot bed.

[Mr.Hotwire]

Here is a video of what I am talking about the wobble in the rods:

https://youtu.be/7sdZNw8r8xk

[William]

Hi, have you tried taking the hotbed to see if it is level?

[Mr.Hotwire]

I put a straight edge on the glass bed, and the glass bed its self is flat. The glass bed is held to the heat bed by bulldog clips, not enough pressure to bend the glass. I checked both sides of the glass just in case one side was thicker in the center then the other side.

[William]

Hi, you need to use an insulated long tail clip to secure the glass plate to the hotbed to prevent the glass from oscillating to effect printing.

[Mr.Hotwire]

This is a bulldog clip :

bulldog.jpg (4.27 KiB) Viewed 14549 times

There are 4, one at each corner of the glass to fasten it to the heated bed.

The glass is flat, the 4 corners all are the same distance from the nozzle (2 sheets of paper), but in the center, the nozzle is against the glass bed... that is flat... the gantry is equal / the ends are level to each other.

[William]

Hi, have you checked whether the upper and lower axes of x are the same diameter? Is the locking ring tightened?