Re: 4-AXIS FOAM CUTTER

--- In CAD_CAM_EDM_DRO@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:

> Hi Tim, list,
>
> All this foam! I'd heard about cutting airplane wings for model (?)
> aircraft, but what else is done with it? Casting molds? I know,

Santa

A very common application is cutting dimensional letters for signs,
cut with angled sides. Pick a tru-type font, draw the top shape,
draw another outline at a different Z depth and slightly larger or
smaller. The foam (or wire EDM for steel) will be cut to the same
form. This is usually cut from foam sheets, and the X-Y-U-V axes are
parallel to the X & Y on a vertical mill.

Some common wire edm forms are die clearance, side clearance on
grooving/forming tools for lathes, and extrusion dies for aluminum or
plastic. The entrance hole for an extrusion die is nearly round, and
the exit is shaped like an H or an L , or a U to make extruded
aluminum channels.

> I can't visualize the moving of 4 axis; pairs of "hot wire" ends, to
> shape the foam. I'd like to see a movie (demo) of that! The wire

cuts

> a plane, can it be thought of (and manipulated like) a wood rasp?

This

> motion is NOT like any tool path I can think of. A ball mill

moving in

> 3D I can visualize, this wire tilting and moving I cannot.
>

See page 222 in the new Vector manual or file open wire4ax.ccd in the
Vector installation directory.

Hot wire is somewhat limited for making airfoils, in that it cannot
make a fully controlled changing airfoil cross section. It can make
a varying one, but the only control points are at the ends. Hot wire
will not let you make a "bulge" in the center, nor will it allow the
cross section to extend outside or inside any space defined by the
end points. If you need an airfoil that has a twist like a propellor
or turbine blade for instance, it quickly can fall outside of the
capabilities of 4 axis wire cutting.

Best Regards,

Fred Smith
IMService