Quote Originally Posted by JoeHarris View Post
I saw the 10mm pitch threads too but now I have the 1605 I'm sticking to my guns. The results dean gets from 1605 are plenty good enough for me and if I can get to anywhere close I'll be a happy man!
The thing is, it's not just a question of does the machine work well enough with 1605. If 1610 is used where appropriate, then you will get better acceleration and probably higher feedrates with the same motors. The maths to prove that is simple - moment of inertia (J) of 1610 and 1605 is pretty much identical, but to get the same acceleration 1605 needs to spin twice as fast. Torque is moment of inertia multiplied by angular acceleration (Newton's 2nd law), so since we require double the acceleration the torque is twice as great.
Now you may say that you don't need these benefits, since the 1605s are 'good enough', but the point is if you leave it at the same speed and acceleration as you get with 1605 and use 1610 the required torque from the motors is lower. That means you're running further from the limit, so are less likely to have problems since the system isn't being 'stressed' so much. That's not to say you should immediately sell the 1605 screws, since it's no loss to try it and see.