Bed Leveling/Calibration Help Please

[Dr.Rockzo]

Hi all,

I've been lurking around on the forum for a few weeks now and haven't been able to find an example of the issue I think I'm having; but if I haven't found it yet please point me in the right direction.

I've had a Rostock Max V2 running for a month or so and can successfully print objects that fit into a 5-6" diameter circle in the center of the machine and the turn out pretty nice. But recently I started a project requiring a rectangle of roughly 8"x6" and that's when I discovered an anomaly I haven't been able to adjust out. Here's the meat of the problem, when I do the calibration I get my Z,Y, X towers and center perfect with multiple iterations of end-stop adjustment and Horizontal radius adjustment using a 0.003" feller gauge instead of paper and it's all good in the triangle the towers form; however when I check points opposite of the towers I have positioning errors. I have attached a drawing of what I have found, but basically to the left and right of the Z tower the nozzle is higher that expected and lower than expected across from it. In the drawing the inner circle is 200mm OD and the outer circle is the 280mm OD print area.

I've seen other posts mentioning adjusting the "Alpha" settings, but I don't know if that's the correct area to look at. I have also seen mention of the "Delta Radius" values (not horizontal radius), what does that setting actually do? I haven't messed with it because I like to know what I'm changing; for that matter, what is the "Horizontal Radius" actually changing?

So far I have checked to make sure my glass is flat when heated with a straight edge and a 0.0015" feeler gauge and it checks out.

I'm really at a loss, could it be something a simple shimming the high side of the bed and resetting the Z-height? Do I need to change something else in the firmware? Should a sacrifice a chicken?

I would appreciate any help or suggestions, I know you guys know these machines very well.

Thanks!
-Tony

[lightninjay]

You may be interested in immersing yourself in this thread. Read as much as you can, and if it does not sound similar to what I think you're describing, we can work from there.

Best of luck!

[nitewatchman]

Have you checked the perpendicularity of your towers to the bed. Looking at you numbers suggest that the X and Y towers may be leaning away from center and that the Z tower may be leaning towards center.


Just a guess.

[Dr.Rockzo]

Hi all,

Sorry for my delayed response, been away from the computer...

ligthninjay - I did find that thread in my searching, I will re-read it and see what I can find.

nitewatchman - I will check for square on the towers but everything seem fairly tight fitting, any advice on making adjustments if needed?

Thanks for the help!

-Tony

[nitewatchman]

I found that on mine even though the towers fit tight in the base if the clamps were loosend the top could be moved quite a bit.

[Dr.Rockzo]

Thanks for the responses guys, I ended up shimming and re-calibrating until I got a level bed.

I'm not entirely sure if it's the technically correct solution but it did get my machine playing nice.

I did find that my towers are off slightly, which is probably the actual cause for my issue, but I can't get them to stay square they just pull back into the position the want to be in...I'll have to play with it more.

[Khalid Khattak]

good to know you have solved the issue.. can you post pictures...