Consistent irregularities in carves (tried forum solutions - need fresh ideas)

X-Carve
1

Hello community,

First off - This is my first question, I’ve been learning a lot from these forums over the years so thanks!

I’ve been using my X-Carve since 2015 (1000mm model with Arduino controller).
Recently my cuts end up with irregular shapes. I’ve attached a circle cut to demonstrate. The odd thing is that it seems very intentional - even with almost no load on the machine (0.1mm depth) I get the same consistent irregularities, and they reappear in exactly the same form with every depth pass / every new cut. Even when I redo the cut at a different position I get the same irregularity again (see 2 circle attempts in the attached photo).

After browsing the forums - I tried checking the machine alignment, straps tensions, wheels, current limiters, reflashed the arduino with latest GRBL version, tried using both EASEL and other software. Seems consistent.

Any tips/ideas would be much appreciated!

Thanks,
Idan

circle
circle1200×1600 94.3 KB

2

I suspect play, on the wheels and/or belts (or set screws on the belt pulleys)

The X and Y axis have different amount of “slack” causing a positional drift when the motion transition from X to Y and vice versa.

Do both of your Y-motors work okay?

3

Thanks for the reply.

I re-checked for play/slack on the wheels/belts/pulleys and they seem ok.
Also I verified that both Y motors are working (and tried to “jolt” the different parts to look for slack in X/Y but it seems pretty firm)

4

Just updating in case someone encounters a similar problem.
The problem was opposite from the usual - things got over tightened. I released the X axis set screws a little bit - so that the wheels can turn a little more freely (still without play). Coupled with increasing the current pots for the X axis.
All works great now.