HEIDENHAIN CNC Pilot 4290 - Manual (Page 105)

HEIDENHAIN CNC PILOT 4290 93
Feed rate reduction factor G38-Geo
Special feed rate for G890
Parameters
E:
Special feed factor (0 < E <= 1) – default: 1
(special feed rate = active feed rate * E)
Programming notes
■ G38 is a non-modal function.
■ G38 is programmed before the contour element for
which it is destined.
■ G38 replaces another special feed rate or
programmed peak-to-valley height.
The ”special feed rate” is valid only for
basic contour elements.
Only use peak-to-valley height (”V, RH”),
finishing allowance (”F”) and special feed
rate (”E”) alternately!
Attributes for superimposed elements G39 Geo
Influences G890 in the override elements (form elements):
■ Chamfers/rounding arcs (for connecting basic elements)
■ Undercuts
■ Recesses
Machining factors influenced:
■ Special feed rate
■ Peak-to-valley height
■ Additive D compensation
■ Equidistant oversizes
Parameters
F:
Feed per revolution
V: Type of surface texture (see also DIN 4768)
■ V=1: General roughness (profile depth) Rt1
■ V=2: Average roughness Ra
■ V=3: Mean roughness Rz
RH: Peak-to-valley height (µm, inch mode: µinch)
D: Number of the additive compensation (901 <= D <= 916)
P: Finishing allowance (radius)
H: (Translation of P) absolute / additive – default: 0
■ H=0: P replaces G57/G58 oversizes
■ H=1: P is added to G57/G58 oversizes
E: Special feed factor (0 < E <= 1) – default: 1
(special feed rate = active feed rate * E)
Programming notes
■ G39 is a non-modal function.
■ G39 is programmed beforethe contour element for
which it is destined.
■ G50 preceding a cycle (MACHINING section)
cancels a finishing allowance programmed for that
cycle with G39.
4.5 Geometry Commands