How accurate should the bed level sensor be?

Ender Series Creality Ender-3 S
1

I have had nothing but difficulty printing a reasonable first layer for a very long time. I just cant get it consistent. It seems good at the end of one day and in the morning it is almost time to start over. I have done this several times. I’m beginning to wonder if maybe the bed leveling sensor is just not good enough. I did three tests just now and wrote down the values for the center 9 positions that it reads and some are very off. Is this a problem? or should I just look somewhere else.

[ 7, 8, 9, 12, 13, 14, 17, 18, 19]
-.03, -.07, -.04, -.09, -.07, -.01, -.03, .01, .02
-.07, -.02, -.09, -.09, -.01, -.04, -.01, .07, .01
-.11, -.05, -.01, -.07, -.06, -.13, -.03, .01, .00

Range
.09, .06, .09, .03, .07, .13, .03, .07, .03

I picked the center most locations because most things print in that center block. As you can see 6 of the 9 spots vary by greater than .05mm.

This all really started when I added the Sonic Pad to my printer. I have not had even reasonable results since then. When I look in the ,cfg files The numbers for the mesh and the number for the z offset don’t even look close to what is shown on the sonic pad, the sonic pad doesn.t even show a number for the z offset.

2

It is the overall range, your lowest minus your highest. Also, bed meshes should be done at your normal bed printing temperature because the aluminum bed will grow and shrink during heating and cooling.

Here is mine at 100C for printing ASA.

IMG_0334
IMG_0334712×615 26.9 KB

3

Using Fluidd, click on the tune icon, can you get to the mesh and post it please.

4

Here is what it looks like now.

bedImage
bedImage480×270 19.9 KB

If you need other images I can get them.

5

Was rather hoping for the figures that go with it from the Fluidd screen.

6

bedImage
bedImage1570×567 78.5 KB

is this what you want? I don’t know how to show the values.

7

Variance of 0.25mm is very good, autolevelling can cope with almost 2mm.

8

What happens is the variance changes everytime I run the , I have seen it go from .5 to .15. On different prints on the first layer I can see the individual strands of the filament, sometimes it is good.

9

I think then your z-offset is too high. Try and tune it in on a wide skirt or brim.

10

I have done that many times. I manually level the bed using the springs and wheels. I set the z offset with a piece of thermal paper at about .5mm . I then use the auto level feature and print a set of 1 layer squares around the corner and center of the bed. After I lower the z offset 5mm or 6mm it still isn’t close enough. I have once made 7 adjustments it still isn’t good enough. I can’t tell what the z offset is, as I lower it, the value in the cfg file goes up and has a strange relationship to the actual number. Once set in the config, I cann’t see what the number is as I change it to get it better.

11

Springs and wheels please clarify which printer we are discussing.

12

Ender 3 S1 Pro with a Sonic Pad. All of this has happened since I started to use the Sonic Pad.

13

Have you considered replacing springs with silicone? I have done this on my Ender 5 plus and rarely have to relevel it now.

1 Like
14

I have looked into it. At this time I don’t need another variable in this effort to get a consistent first layer. I know it doesn’t cost very much, but I don’t see how it will solve the problem I’m trying to solve. If you think it will it will be easy to change.

15

It has been more stable with silicone than the uprated yellow springs.

1 Like
16

thanks, I’ll give them a try. Appreciate your perspective.

17

This is one I saw just now. This afternoon I have had a terrible time at binding the print to the bed, haven’t paid attention to the variance, I really think I have to replace the sensor.

bedImageII
bedImageII1425×558 65.7 KB

18

Wow, that’s perfectly level compared to mine :grin:

19

I think the issue is that the next time the white area will be in the rear right corner or the entire rear.

20

Does your bed rock on the linear rods? Wondering if the bearings are loose on the carriage or they are loose on the rods.