Also note that some CNC controls will do their own Spline
interpolation as well if properly programmed.
Your CAD/CAM or CAM system needs to output the correct data
for them though. This vastly reduces the amount of data and produces
accurate, smooth curves at the machine.
Sort of like interpolating arcs with the control (G02 or G03) but
with splines. It may also be an option on some controls.
Best way to go by far if you can, usually.
What CAD/CAM or CAM system(s) and control(s) are involved?
Some in NG alt.machines.cnc probably know them. Not jb though.
HTH
I'm using Procam by teksoft. A hideous program I hope to be rid of
very soon. The controller is a Fanuc, but all programming is done on a
PC.
I ran two programs for the identical profile. PGM1 used a spline and
PGM2 used ARCS. The resullt of the splined path was many short arc
segments being output when posted. In using arcs, the run time was cut
in half in comparrison to the splined path. This is an issue that may
be addressed by the CAM software.
If there is any way to address this from SolidWorks, I'm all for it,
but it looks like I'd better put in an enhancment request to my VAR.
After that, I'll grab a chicken, slit its throat and wave it three
times over my head while standing on one foot. I suspect both actions
will produce the same results.
snipped-for-privacy@aol.com (Cliff Huprich) wrote in message
(d) writes:
Can they output spline data thru their post? I'd ask them.
Many GEFanuc controls these days support Spline interpolation
though it may be a $$ option.
Does yours have it or can it be turned on by the machine's maker or
by GEFanuc?
It would probably have to be unless you listen to jb & try to dimension
splines & then ask someone else to MDI the program at the control <G>.
But you had tolerance control (INTOL/OUTTOL) in the first case but had
to do manual approximations with the arc fitting in the latter (even though
the resultant arcs did not need to have tolerance later applied.)
You might also have some control options you have missed that
govern it's operation .. look for "exact stop" and such in the manuals
in the G code listings. Some controls can be forced to make exact
moves or be allowed to be "pretty close" before processing the next
block. The latter option, if available, may speed things up with no
problems, depending.
Post your info on your machine & control to alt.machines.cnc ...
with the question about "exact stop" and someone may know.
Also see the following posts; they may help get you started:
<http://groups.google.com/groups?as_q nuc&numP&as_scoring=r&hl=en&ie=I
SO-8859-1&btnG=Google+Search&as_epq=exact+stop&as_oq=&as_eq=&as_ugroup=alt
.machines.cnc&as_usubject=&as_uauthors=&as_umsgid=&lr=&as_drrb=q&as_qdr=&a
s_mind&as_minm=5&as_miny81&as_maxd=2&as_maxm&as_maxy 03&safe=off>
Well, ......
(The program I mentioned in an earlier post does the arc fitting to the
CNC G-code AFTER it's posted IIRC. No need to do any manual
fitting or approximation. Still, IF you can get spline interpolation to
work ...)
I don't think it's a SW issue as SW is a CAD program, not a CAD/CAM
or CAM program. (I know, jb always gets them confused.)
Story Time:
I've actually done something similar to that with some Polyurethane
processing equipment & production of shoes It DID work. Last
resort sort of thing ....
Never did know why it worked (at the time).
Seemed that if we started getting "blisters" on the parts the only way
to solve the problem (we only had it on my shift .. the day shift & forman
never had it) was to stop productiion, tear down the mixing equipment
and clean it all (which involved burning polymer off mixing impellers too).
Waving the burning impellers about while they smoked seemed to help
the problem go away.
Actual problem (discovered long, long too late)::We were making
at least twice as many parts per shift as the other shift due to better
organization & coordination among the shift's members.
As a result the tooling (molds) were somewhat overheating ... the
downtime while we cleaned (other shift did minimal cleaning) allowed
them to cool just enough ... and the molds were still a bit warm from
first shift when we started. They got a good chance to cool down
before first shift started again ...
HTH
Well, you could use CAMworks, which is Teksofts SW machining plugin.
you could call it "A hideous program LITE" haa haa.
Last I checked, Camworks used ProCams posts.
Already gave you the "ultimate solution" ... redraw the part
in your CAM system.
What is the tolerance you must hold on this part ? If it's
not extremely tight, DP Esprit X *always* produced smaller
files for me on polyline conversions.
jon
<snicker>
What a total idiot of a moron.
Plot the thing & duct tape it to the monitor & trace too?
Loved that Bezier curve thing some time back .... "just dimension
te Bezier curve and give the picture to the machinist for MDI input ...."
So would a straight line.
Clearly, again, you know very, very little of such things.
Have you actually even seen any of the software you tout?
Much less actually used it?
Repeating work is hardly an "Ultimate" solution, at least imo.....
That's what I'm doing now. Buying another CAM system because is not an
option either.
are
good
What choice do you have with SolidWorks and ProCAM ? Even if
you were using DP Esprit, when you convert from polylines to
arcs you are going to loose some degree of accuracy. Many
times this does not matter if your tolerance is wide open as
many profiles often are.
At one time both MasterCAM and SUFRCAM were suppose to run
inside of SolidWorks. Why do you think both companies killed
development on their respective projects ??? I got an ear
full from the former SURFWARE employee who acted as liaison
between SURFWARE's owners and SolidWorks Corp. on how difficult
SolidWorks Corp. was to work with. Have no doubt there was at
least some truth in what he had to say. I have heard the same from
Robert White former owner of FastSURF and several others at
CAD/CAM companies who need to remain nameless.
It's pretty common knowledge that SolidWorks Corp. does not
spend a lot of time thinking about many of the tools that
are needed to actually manufacture a part. This has been the
case for a long, long time now.
Why not use something like Rhino to clean up the mess that
SolidWorks puts out ? By the time SolidWorks Corp. fixes the problem
you and I will both be very old.
jon
Never have a clue do you? Even know what the subject is?
BTW, Did anyone try IGES? ProCAM says they use it ...
Guess who said that.
When you copy things from my posts (and sometimes
slightly rephrase a little of it) to post as your own to
http://www.cadchat.com/forums/ (or other places) you should
provide proper credit.
Someone at http://www.cadchat.com/forums/ (or other places)
might ask you what the words actually mean.
Like the scrap you made on that wire EDM that one week they
let you push the GREEN button (per your claims)? Lost that job
right after I think ... the did the job & reference check a bit late I
gather.
(Anybody interested in his post on how to lie at a job interview?)
Was that in the press release you copied & posted? LOL ...
Money & market share?
Bill Gibbs still under your pillow?
Whispering the secrets of CAD/CAM in your ear late at night
as the Lithium wears off?
"Since Karen Bean's in house lawyer quickly muzzled Dave
Saulnier from talking to me I have no idea how much David
has progressed with implementing the ACIS surfacing routines
that are available in the ACIS kernel." -- jb
Because you don't have any names to drop?
Copied from *someone else's posts* (or ads) somewhere?
What part of "It's a CAD system" don't you grasp?
After how many years is this idiot still clueless?
So go buy a CAD/CAM or CAM system.
Where did you get it from? LOL ....
About the time some vendor next gives you a free demo, right?
I note you refused John's kind offer of a live demo of TopSolid
<snicker>.
No idiot cures there .....
Nose getting better? LOL ...
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