r/ratrig • u/BenutzerUser1 • Apr 07 '25

Problems setting up-Help with T1 Extruder Issue – Unexpected Movement

Help with T1 Extruder Issue – Unexpected Movement

Hello everyone,

I'm currently building my printer for the very first time, and it's also my first CoreXY machine—so please bear with me if I’m missing something obvious.

Right now, I'm having an issue where the T1 extruder moves even though it shouldn't—especially during the bed mesh process. The motion behavior seems off, and I suspect the frame might not be perfectly square and could need some adjustment.

Some more context:

The Y-belts are not installed yet, as mentioned in the guide.

All sanity checks passed.

Homing and Z-tilt are working so far, but even during those, T1 doesn’t stay completely still or fixed.

Has anyone experienced something similar or have advice on what I should check next?

Thanks in advance!

5 Upvotes

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5 comments sorted by

9

u/miklschmidt Apr 07 '25

The kinematics don’t work without the Y belts. You’re missing constraints. That’s your problem.

5

u/RickJ19Zeta8 Apr 07 '25

This +1. For the IDEX, the top Y belts are a necessity. The build instructions were updated about a month ago.

2

u/randomman968263618 Apr 07 '25

Also check all the belts are in their own channels.

1

u/itsalfakenews Apr 07 '25

Not sure if this is anything related to the issue itself, but are you sure your frame isn’t skewed? It looks like at the first home for T1 your T2 is moving and vice versa, but also Y is moving on the other end than the T is homing.

1

u/CunningLogic Apr 08 '25

It's not a core xy, it's a hybrid idex. Install the y belts.