Question about mounting Nylock/Spring/Silicone Mod for MK2.5S
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Question about mounting Nylock/Spring/Silicone Mod for MK2.5S  

Estimable Member
Question about mounting Nylock/Spring/Silicone Mod for MK2.5S

I am trying to get the very best out of my MK2.5S. 
Because the heatbed is warping (difference about 1 mm between outer corners) I want to check all mechanics and at the same time add a mod to be able to do the first leveling mechanically. I guess by now I have read about 20 or more blogs/forumthreads/website about the subject. 
But still a couple of questions unanswered (maybe some of you remember how they did this exactly?). 
On my machine the heatbed is mounted with a standoff + two screws. There is a simple hole in the frame. 
My idea is that the nylock mod will not work, unless I find something to get the screw attached to the frame on the otherside. 
Maybe there is a trick? 
For mechanics I like the springmod idea best. Most controlled solution. Again the question how to mount it? 
I think I could solve this by using a longer screw; a spring between bed and frame; and a nut at underside of the frame.
Question here is: How to prevent the nut from turning when I adjust? BTW I could use a nylock nut here to keep screw in position (in the nut). 
Question 3
Any other advice (better/best methods?)
Regards, Eef

Posted : 20/04/2024 12:07 pm
Estimable Member
Topic starter answered:
RE: Question about mounting Nylock/Spring/Silicone Mod for MK2.5S

Update (answering my own questions): 
- the holes of the heatbed are NOT threaded, so I had to use a nut to fix the screw (going through the spring) 
- I used flat nuts (1.8mm) to prevent the nuts at the back to hit the frame. (now there is just about a 1mm gap. Not much but enough)
- I could find springs who can be pressed down to about 4 mm and tight enough to easily hold the bed.
- The two screws + adjusters in the middle of the bed (MK2.5) are place back as they were. 
- adjusting the 4 outer screws is very easy. The nuts do not turn along, and if they would it is easy to just hold them tight with a finger. 

I also took the opportunity to exchange the bearings of the Y-axis with drylin bearings. (this because there was play in the bearing). 
And discovered that the Y-axis were not mounted correctly. At the back and front the axis were mounted about 0.1 - 0.2 mm to far to the outside. The bearings run fine in the middle, but as soon they reached the end of the Y-axis, moving was hard. 
So most important tool: calipers. To measure + remeasure those distances. 
Adjusted them, and now the printer is moving more flexibel. The printed surfaces are more smooth then ever before. 

Octoprint was used to adjust the heatbed. 
- Use one of the adjusters to set al spring/screws to about 5 mm
- Z- calibration, to get a good base to work on. 
- Run the adjustment plugin in Octoprint, change the screws a bit; repeat, until the variance is back to about 0,11 mm
- I think I will repeat this in 1-2 weeks, to see if it is settled in the new placement. 

Posted : 29/04/2024 9:44 pm