My router cuts out of place

Hello!
Recently I finished building my router, it uses a Dremel 3000, Nema 17 motors, Arduino UNO, and A4988 drivers with a cooling fan. I am making my cutting programs with Vectric and run them with GRBL.

The issue I am observing, is that after a couple of cuts, my router starts cutting out of place, for example, it cuts some holes in the right place, moves to the next position and the place where it plunges is out of place i.e the final part is not correct.

I have been playing a while with accelerations (my leadscrews advance 2mm per rev, and acceleration is currently at 18 mm/s^2) trying to fine tune the machine but I havent reached the sweet spot yet, any siggestions are highly appreciated.

 

Hello Giarc, thank you for your reply.

Due to the fan that is continuously blowing over the drivers and shield, they don´t get hot. I don´t think that the drivers are loosing steps, the contours look exactley the way they should, the only issue is that they are not in the right place. For example, I tried to cut a smiley face. The cutting program was set to cut the eyes and smile first and the face contour afterwards. The eyes and smile positions match with each other and cut depth is ok, however the face´s circle is off.

Do you think there could be another issue besides a bad driver? I was thinking maybe acceleration or another parameter could be causing the router to go crazy.

Thanks.

 

Thanks for the info Peter. Hopefully I will improve my HW when I have some $$, in the meantime i will try what you suggest.

 

Hello, here is an example. The hole should be centered in the oval contour and it is moved. The cutting program was made with Vectric Aspire. First it makes the hole and then it moves to cut the outer oval contour.

 

Hello.

Yes, the simulation in vectric looks ok, it just behaves strange when I run the cut in the machine.