NordicCNC's build log

[pippin88]

Add a second spindle bracket up high on the spindle.

Add ribs on the edge of the Z axis plates. This will add a huge amount to stiffness. (Essentially make them into C channels).
Nowhere on the machine should you have a simple flat plate - everything should be box sections of at all possible, otherwise should have stiffening ribs.

[NordicCnc]

Add a second spindle bracket up high on the spindle.

According to the spindle specification, the clamping area is defined here:



I am afraid that clamping higher up (I am at the highest allowed point already) could potentially damage the spindle. Please correct me if I am wrong? The reason why the spindle is clamped like this is for gantry clearance.

Add ribs on the edge of the Z axis plates. This will add a huge amount to stiffness. (Essentially make them into C channels).
Nowhere on the machine should you have a simple flat plate - everything should be box sections of at all possible, otherwise should have stiffening ribs.

Good point! While I am trying to keep the Z-axis weight low, I think adding 15mm aluminium stiffening ribs wouldn't be too harmful (only around 1.2kg added). If I understood you correctly, you means something similar to this:



Additionally I could also move the Z-axis linear rail spacers to the front plate. This would increase the moving weight by another 1kg. I am not sure fi I should keep them on the rear plate or not. I could move them to the front plate and add stiffening ribs to the back of the rear plate. The ribs would be bolted to the rear plate, top bearing plate and motor bracket, effectively forming a rigid box. Is this just adding dead weight?

[AndyUK]

The ribs would be bolted to the rear plate, top bearing plate and motor bracket, effectively forming a rigid box. Is this just adding dead weight?

Machines only as strong as its weakest point. Currently what is keeping the back of your Z axis still? Its those carriages, which are attached via a 90 degree but-joint. So I'd say those two or so screws are the weakest point! That's why I created the side plates on my Z axis to give some support to the joints.