NordicCNC's build log

[NordicCnc]

Here's where I throw a spanner in the works.

This is from my own way of working I think you are going way overboard with the construction of the Z axis adding more and more to it.

I made a Z axis 510mm high x 220mm wide using 12mm backing plate with cut outs to ease the weight on the Y axis with 20mm Hywin rails direct on the plate no packers and carriages direct on the spindle plate, I made a rotating ball nut and fixed 1605 screw which helps to have the very minimum of overhang and adds to the strength of the design.


It carries a German 2.2kw water cooled spindle, (I know not as heavy as yours) I do not get any drop of the Z when powered off weather this is down to the 2 to 1 reduction to the nut I am not sure but it works very well, it has cut wood, plastics, aluminium, steel plate and stone with no problems whatsoever.

Recently I setup a 4th axis to cut 2 1/2D designs around the edges of 150mm disks again works really well.
I am currently designing another machine with extended Y axis to be able to have a 4th axis running down the length of the X axis, and be able to cut around 300mm dia disks and have no problem using the same kind of design in fact I am going to use a rotating ball nut on the X & Y axis as well it is more compact and so smooth compared to turning screws.


Phill

Hello, looks good! Interesting with the rotating ball nut. I understand it so that you have placed the fixed bearing on the spindle plate and then the other ball screw end is lose. Does it stick up in the air or what does it look like when the Z-axis is fully retracted?

Anyway I have to say that your advice is quite contradicting compared to the advice I have received from others. I am not saying you are wrong but I try to stay open minded!

[phill05]

Hello, looks good! Interesting with the rotating ball nut. I understand it so that you have placed the fixed bearing on the spindle plate and then the other ball screw end is lose. Does it stick up in the air or what does it look like when the Z-axis is fully retracted?

Anyway I have to say that your advice is quite contradicting compared to the advice I have received from others. I am not saying you are wrong but I try to stay open minded!

I did say I was throwing a spanner in the works, I know it's not a conventional way of making this and yes contradicting to what has gone before but it works and works really well it is compact, less weight, and the machine cuts very well, just wanted to give you an idea of what works without going to far.

The screw is bolted tight to bottom of spindle plate (no bearing) and screw goes up with plate, attached is an image when I first put it together.


Phill

[NordicCnc]

I did say I was throwing a spanner in the works, I know it's not a conventional way of making this and yes contradicting to what has gone before but it works and works really well it is compact, less weight, and the machine cuts very well, just wanted to give you an idea of what works without going to far.

The screw is bolted tight to bottom of spindle plate (no bearing) and screw goes up with plate, attached is an image when I first put it together.


Phill

Oh my! You have quite some Z-axis travel height there. I can see that the screw will be sticking out in the air when Z-axis is fully retracted (at the top end position). I think you rarely use that Z-height or are you doing some custom jobs?

Looks like the gantry clearance is around 100-120mm, am I right? It would also be interesting seeing a video of its performance in aluminium/steel!

You have definitely given me something to consider, thanks for that.