MPCNC cutting issues

[kev1990n (Kevin)]

Dear MPCNC’ers,

I have been working on my MPCNC for a while now and keep running into the same problem over and over.

Since I haven’t found any topic describing the exact same problem, I have decided to start one.

The problem i’m having is the machine SEEMS to keep ‘hanging’/gets ‘stuck’ on random point, causing the whole print to get off course.

I’ve tried A LOT to come up with a solution on my own. Since i can’t seem to solve it on my own i’m hoping someone could point me in the right direction (any help is greatly appreciated).

My attempts so far:

• reassebled middle assembly;
• reflashed firmware;
• rewired everything;
• upgraded to the best quality rods I could find;
• added corner supports;
• upgraded routers (Chinese to Makita);
• tried different belt tensions;
• tried different xy speedsettings in Estlcam and feedrates (tried 1200, 1600 and 2400);
• tried various bits (currently using an 1/8 (3mm) 2 flute end mill

Possible problems which I believe are definitely not the cause:

• Router(s)
• Rods
• gcode file (one cut turned out perferct)

Since pictures probably are a lot more explanatory, i have added these. Furthermore i have uploaded a video on YouTube (note that this was made before I swapped routers and before i rebuilt the middle assebly). In the video you can hear the motors struggling at around 01:00, around 01:30 things go really wrong.

Video link: https://youtu.be/JGL2vWeUtsY

 

These things should all be included in your post. It makes it much faster to diagnose problems.

1. Did you buy everything from here? - No.
   a)If you didn’t or changed some things please don’t leave out any details and include what firmware you flashed. - Used firmware from Vicious website.

2. Are you using end stops? - No.

3. Mac or PC? - PC.

4. Include a picture so obvious errors might be spotted. - Added.

[vicious1 (Ryan)]

Looks like you are using the ESTLCAM firmware, please re-flash back to my marlin one and see if it goes away. I think your settings are incorrect in the estlcam and you are overloading the processor.

 

[kev1990n (Kevin)]

Extra pictures.

Also noteworthly: there is zero play in the frame,

z-assembly is nice and rigid (runs smooth, and has no play),

relative simple cuts seem to go ok (mostly),

I’m cutting at a depth of 2mm per layer (also tried 1mm),

It is mostly the second or later layer where things go noticably wrong/off (first layer is mostly ok).

[vicious1 (Ryan)]

In your “estlcam settings 2” picture you are missing the most important number, the z max feedrate. That is overloading the processor and freezing it.

[kev1990n (Kevin)]

Thanks for your quick responce. Will give that a try and let you know.

For completeness’ sake, could you point me to the right link containing the firmware?

[vicious1 (Ryan)]

First this, https://www.v1engineering.com/marlin-firmware/

Then triple check this, step by step and you can run my gcode at the end to test.

https://www.v1engineering.com/estlcam-basics/

 

[kev1990n (Kevin)]

Thanks. Will flash that firmware tomorrow.

I did the ‘crown’ test drawing after completion of my build and that turned out perfect.

[kev1990n (Kevin)]

Is the recommended z max feedrate of ‘480’ also the recommended value when using a T8 lead screw (instead of a threaded rod), or should a different value be used in Estlcam?

[jeffeb3]

Did you adjust the stepper motor drivers?

[vicious1 (Ryan)]

You can go up to 1800 with a t8, but should stay under that.