Re: Smithy Granite

--- In CAD_CAM_EDM_DRO@y..., "Chris Clough" <cclough@x> wrote:

> I need to cut 3/8" to 1/2" flanges; will a CNC mill do it
> with the right bit

> its accuracy just isn't where I
> want it - that's the nature of the beast with a plasma cutter

though.

Chris, what is the tolerance and what kind of details are you trying
to machine? What size are your parts, X-Y-Z extents? The answers to
these questions will have a big impact on getting a straight answer
as to whether or not a benchtop or 3-in-1 CNC mill will work or not.

Do you need tight hole location AND size/finish?

You may find that the best solution is to rough the material out with
the plasma, and then finish it with a mill. The plasma is far and
away a better tool for removing large chunks of metal within the id
or OD of a flange. It is not too good at spotting and drilling a
precise bolthole circle around the periphery of the flange, and the
edges will always be a little jagged looking. You might need to
leave .06-.1 inch all around for mill cleanup, but if you have to
mill that contour without the plasma, it will take much longer,
require full flood coolant, and wear out many endmills.

If the parts are round (and I'm imagining them to be 5-7 inches in
diameter), you may be able to use the lathe portion of the Smithy to
finish OD & ID, and mount an indexing control to the spindle and a
driven tool on the compound for a bolt circle, without having to
change setups from lathe to mill. You will still want to burn the od
& id with the plasma to start the process.

If you just have a few parts, maybe you can use a drill jig for the
bolt hole circles, and just finish the od & id on the lathe.

Best Regards,

Fred Smith
IMService