Fagor 8070 BL, Руководство по программированию

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Programming manual.
CNC 8070
20.
HSC. HIGH SPEED
MACHININ
G
.
Recommend
ation
s
for ma
ch
ini
ng.
·362·
(R
EF
: 1709)
20.1 Recommendations for machining.
S e l e c t i n g t h e c h o r d a l e r r o r a t t h e C N C a n d a t t h e p o s t -
processed CAM.
As mentioned earlier, the error caused by the CNC between the programmed part and the
resulting part is never greater than the programmed value. On the other hand, the CAM
system also generates an error when processing the original part and converting the paths
into a CNC program. The resulting error may be the sum of the two; therefore, the desired
maximum error must be spread between both processes.
Selecting a large chordal error when generating the program and a small chordal error when
executing it, the execution is slower and of lower quality. In this case ridges will appear
because the CNC perfectly follows the CAM generated polyhedron. It is recommended to
post-process at the CAM with a smaller error than the desired one for high speed cutting
HSC (between 10% and 20%). For example, for a maximum error of 50 microns, we should
post-process with an error of 5 or 10 microns and program the 50 microns in the HSC
command (#HSC ON [CONTERROR E0.050]). This way of programming lets CNC modify
the profile while respecting the dynamics of each axis without causing undesired effects like
ridges. If CAM post-processing is done with the desired error and a very small error is
programmed in HSC CONTERROR, as a result, the CNC will follow faithfully the facets
generated by the CAM.
The part-program.
Since the CNC works with an accuracy of nanometers, better results may be obtained if the
coordinate have 4 or 5 decimals than if they only have 2 or 3.
Post-.processing in CAM with an error smaller than the desired one for machining with HSC.
Post- processing in CAM with the desired error and HSC machining with a very small programmed
error (CONTERROR).
e
Desired tool path.
Tool path generated by the CAM.
Tool path machined (followed) by the CNC.
e = Error generated by the CAM.
e
Desired tool path.
Tool path generated by the CAM.
Tool path machined (followed) by the CNC.
e = Error generated by the CAM.