Re: [CAD_CAM_EDM_DRO] Re: Bigger is better

From: <currinh@...>

>
> I may not understand what you are doing, and I am certainly not as
> knowledgable as some on this list, but for what it's worth:

Shoot away, man.
*Any* input is something I can learn from right now.

> If I remember you were talking of small steppers, some 150 oz-in, and
> then mentioned needing 650+ oz-in for your mill. Now are you
> considering larger? If I understand correctly, a larger than needed
> stepper will not give the speed of a smaller, will be physically
> larger and cost more.

Sorry for the confusion.
The small ones are for a plasma cutter CNC,
and the large ones are for my mill.
Doing the math, I came up with 611 oz/in of required torque
to make the X & Y move when my big vise is mounted.
Everything I've seen that big so far,
(which has been what...two weeks I've been here?) seems
to jump right to 750 oz/in as a size, so I figured those would work.

> I'm converting my 9x42 knee mill for CNC and have X & Y going. From
> what I could learn reviewing other conversions I figured I needed 650
> oz-in motors. I am using 750 oz-in from Camtronics and they work well.
> I don't feel any larger would be better. I don't know the size of the
> mill you are converting but mine is at least one reference point.
>
> Hope this is of some use.

Abso-phukk'n-lutely~!
I'm using my Rong Fu benchtop for the conversion.
My reasoning for the excitement at Carl's letter was because I figured
that they would probably have a good selection to choose from, and the
fact that most of what I've seen or heard negative about steppers so far
(two weeks) about them missing steps is that it comes from asking too
much from a given size and speed of motor.
So, if I need 611 oz/in, I thought that I should bump it up a little bit
to allow some fudge factor for operation.

Thanks,

Weyland