Rotating ball nut, Ballscrew Pitch, RPM limits, and my particular build pickle

[JAZZCNC]

What is your experience with cheap Chinese ones vs the branded,JazzCNC? 32mm pitch seems a lot, but I see that it does seem popular to match pitch to dia...

Depends where you buy from in China.? Chia's ball-screws where you bought those from are far inferior to those Fred at BST sell's.!

Also branded is a loose term because like most things there are good and not so good brands, Then you have to consider that you are actually trying to compare apples with oranges because it's not realistic to expect something that cost's $20 compared to something which costs $200 to be even close to equal.

My experience is that Branded screws are far superior to Chinese screws which is what I would expect given they cost 3 to 4 times the price.
However, my experience also shows me that even for relatively heavy hobby/light industrial use the better Chinese ball-screws are more than good enough for a CNC router provided you accept that they are not going to last forever and at some point, down the round, they will need replacing. But when you consider you could probably buy 4 sets for the price of one single new THK C5 ground screw this isn't such a bad thing for a hobby user or small business who can afford a little downtime.

End of the day you have to be realistic.!

Re the 32mm pitch, with a 3:1 ratio the pitch is equal to 10mm or 16mm with 2:1 however the rotation speed drops from 3000rpm to 1000rpm which is better for the ball-nut.
However, there is a price to pay in that the torque is reduced, but this is offset some by the ratio increasing torque. But for this application lowering the rotational speed is more beneficial than losing a little torque when you have more than enough spare.!