Kia ora!

Ive been exploring this wonderful forum gathering information before i start my build.

I will be casting a gantry type cnc router with approximate build volume of 700mm x 500mm x 150mm out of cast iron from a local foundry.

I will be primarily cutting Aluminum, but of coarse i aim to try cut Steel. I am based in NZ and only have single phase electricity.

Can anyone help me choose the best spindle for this sort of application? I have found these 2 so far which i think will be good contenders as they are both 4 pole.

https://www.aliexpress.com/item/3298...archweb201603_

or

https://www.aliexpress.com/item/4001...archweb201603_

I have to admit im a little confused between the 2 as one is 800hz and one is 400hz. Which one would be better at low RPM?

I also noticed that the GDK80-12Z/2.2 spindle claims 1500 - 12000rpm in the link below. But doesnt claim it in the above link.

https://www.aliexpress.com/item/4000...%2315609%23235

Cheers,

Rohan