Shapeoko 3XXL cut away from the assigned path

[chayyaz (Ayyaz Ahmad)]

My SO3 XXL cuts away from the assigned path. I have added enough passes on the 1/4 up cut bit for it to not feel significant resistance. It completed 75% and then all of a sudden cut into material. I tried again and same thing happened but at a different location.

It is supposed to stay act the outer profile in the top corner but it turned and started cutting into material.

[gdon_2003 (Guy Donham)]

SO3 loses steps for a couple of reasons.

1. Mechanical issue like belt tension or the pulley on the stepper motor is loose. There are two set screws and one should over the flat of the stepper motor. This is a high probability of losing steps on an SO3.
2. The second reason can be too aggressive cutting parameters. The SO3 is a belt driven machine and you should stick to recommended feeds and speeds for an SO3.
3. The third reason can be mechanical like your v-wheels are dirty, cracked or not adjusted properly.
4. Power off your SO3 and slowly move your gantry front to back a few times. If there is any tight spots address why before moving on. After the front to back then move the router left and right a few times. Move slowly or it will sound like the belts are slipping because the stepper motors create electro motive force (EMF) and that causes the motor to feel like it is binding up. Again if you find any tight spots address that. You may need to inspect your v-wheels. The lower two on the Z are adjustabe and if you lift up on the Z it should not really move. Also the two bottom v-wheels on each end of the gantry are also adjustable. Lift up and you should not feel the gantry move up and down. If any of your v-wheels have movement up and down then adjust them. To adjust them use an allen wrench and loosen the bolt. Use the correct wrench and adjust the eccentric until the v-wheels are touching and no slack up and down. Do not over tighten and flatten the v-wheels. Hold the wrench in place and tighten your allen screws. If you only tighten the allen screws without holding the eccentrics in place it will be over tightened because the torque of tightening the bolt will over tighten the eccentric.

That is a lot of things to check but all should be checked periodically. If you have a Z-Plus and/or HDZ Z then you need to lubricate the bearings periodically. If you have a belt drive Z check your belt tension periodically. The Z belt would not cause your issue but it is still a periodic maintenance item.

The SO3 is a good and reliable machine but going off path is either mechanical issues or your feeds and speeds are too aggressive. Be sure to leave your dust collection hooked up because sometimes the dust collection hose can get in a bind when moving around and that would be considered a mechanical issue.

[chayyaz (Ayyaz Ahmad)]

Thanks for this detailed response. I have a z-plus. I will definitely inspect all you mentioned and try to troubleshoot this issue.

[WillAdams (William Adams (Carbide 3D))]

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