LR3 X gantry drops in the middle

LowRider CNC Troubleshooting
1

I realized my x gantry was low in the middle and thought it might be the conduit so I replaced the two bars with very straight conduit. Once the gantry was assembled I checked it with the edge of my level and everything was straight. Once I got everything back together the sag was back. the carriage position has no effect on it. It has about a 1.5mm low spot in the middle.

My table is very flat and and the min and max z heights are within .04mm of each other. its hard to show with the pics but maybe they will help. I have no idea what could be causing this.

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Any Ideas?

2

No idea really, but are the screws into the wood aligned? Depending on how well the struts came out, there could be some tight spots.

Cheers!

3

The gantry was assembled and straight before I attached the sides. So I’m still at a loss.

4

There are only so many variables, maybe you need better conduit, did you try rotating? How much of a dip? What size table? If it’s 8’ wide, could explain it. :slight_smile: