help w/spline output as DXF

(Cliff Huprich) writes:


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
--
Cliff

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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:

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snipped-for-privacy@hotmail.com (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
--
Cliff

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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.
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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
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<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?
--
Cliff Huprich



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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.

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snipped-for-privacy@hotmail.com (d) writes:

You deserve a cigar for spotting the clueless idiot <G>.
--
Cliff

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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
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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 ...
--
Cliff Huprich

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