Re: Knee for z-axis control?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "jlsmith269"
<jlsmith269@y...> wrote:

> tkis is a "sunk cost" or a condition of hundreds of pounds, fred...
>
> that difference would be EXACTLY the same, knee or quill, as the
> impact would be on the TABLE..
>
> if you move 300 # of weight (which a home guy would do how often?)

to

> any extremes, it would have the SAME effect.

I'm not sure if you are asking a question or making a statement, but
a 300 lb part on the table won't have any impact on the quill
accuracy, if the table is locked. I don't think the table will bend
either.

That does seem like a lot of weight and I didn't think home guys
would move that much too often either. Then along comes home CNC
plasma torches, and a 4 x 8 sheet of 1/4" steel weighs over 300#.
Now if you stack the burnout parts from a couple sheets in a row on
your bridgeport and have at 'em...

For safety sake
1) design in a safety margin that covers a little more (maybe 2-3
times even) than you think you need to move on your table in Z.
2) don't put everybody on the same side of the boat, it'll tip over.

Fred Smith - IMService