Re: Re: CAM in polar format

Ray, thanks for the info. I'm planning on setting up a EMC box, but haven't gotten there yet. I just picked up another hard
drive to install RH 5.2 on. So it shouldn't be long.

I'd like to take a look at the EMC backplotter.

Thanks,

Jay Hayes
Weston, WV


Ray Henry wrote:

> From: Ray Henry <rehenry@...>
>
> Jay
>
> There are some polar coordinate computation routines in the about to be
> released emc backplotter 2.0.0. They are incremental and are used to plot
> the A,B,C axis and the 3D view. Paul Corner wrote them in Tcl.
>
> EMC Backplot only runs on emc but you might be able to extract the routines
> and use them. Let me know if you want to try it.
>
> Ray
>
> >Message: 1 [CAD_CAM_EDM_DRO] Digest Number 363
> > Date: Mon, 14 Feb 2000 08:54:27 -0500
> > From: "Fred Smith" <imserv@...>
> >Subject: Re: CAM in Polar format
> >
> >
> >> From: Jay Hayes <xmas4lites@...>
> >>
> >> I need to convert a simple 2D .dxf CAD drawing of a tool path to a
> >> machine code in a Polar format, of the Vector distance and relative
> >> angular Direction. I can manually write the code or manually extrapolate
> >> the information from the verification functions in Bobcad, but i'm
> >> looking to generate a post processed code automatically.
> >>
> >
> >Tell us a little more Jay. It's not clear if you want to actually program
> >in Polar coordinates, meaning R-Theta type annotation, or something else.
> >What are you trying to program, what machine/control, are you sure you want
> >Relative angular direction or Absolute? What is your orientation to the
> >axes? Bobcad 17 has some very limited rotary translation capabilities and
> >may be able to get the answers you need.
> >
> >
> >Best Regards,
> >
> >Fred Smith
> >IMService
> >
> >imserv@...
> >Phone: 248-486-3600 or 800-386-1670
> >Fax:248-486-3698
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 2
> > Date: Mon, 14 Feb 2000 08:56:40 -0500
> > From: Joe Vicars <jvicars@...>
> >Subject: Display problems with old laptops
> >
> > I am in the process of trying to pick a software controller. I
> >downloaded all the demos I could find, but was dissapointed when I
> >couldn't get DeskNC up on my older 486/386 laptops.
> > Does anyone know how to make DeskNC VGA compatible?
> > I read alot about CNCpro on here as well, how do they compare? The
> >problem is that I can't hardly get Mr. Yeager's demo configured before
> >it times out on me. It's really hard to tell how it's going to work.
> > Any help?
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 3
> > Date: Mon, 14 Feb 2000 08:19:43 -0600
> > From: hansw <hansw@...>
> >Subject: Re: Display problems with old laptops
> >
> >Joe,
> >
> >Joe Vicars wrote:
> >
> >> problem is that I can't hardly get Mr. Yeager's demo configured before
> >> it times out on me. It's really hard to tell how it's going to work.
> >>
> >
> >I agree Doug could have made the demo a little more friendly, and perhaps
> more people would buy it ( hint ! I hope Doug is is
> >reading this)
> >
> >I seem to remembering trying DeskNC (I think) at the time I still had the
> crappie MAXNC controller and the configuration menu
> >was
> >screwed up, it never worked for me.
> >
> >That's when I decided to go Step/Direction and ended up buying CNCPro
> because the was the easiest interface ti handle.
> >
> >Hans Wedemeyer
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 4
> > Date: Mon, 14 Feb 2000 08:32:26 -0700
> > From: Roger Brower <rbrower@...>
> >Subject: Re: CNCPro
> >
> >Jon Anderson Wrote:
> >Snip...radius comp at that time wasn't
> >as high on the list...
> >
> >Yeah, I'd love to have radius
> >compensation in the controller, but
> >that's apparently pretty hard to do,
> >programming wise, with the lookahead
> >function and all.
> >I could be to blame! I probably told
> >Doug I'd do that in the CAM step; Ahha
> >has it? Does EMC do radius comp?
> >reliably? Anybody know how to program
> >it? If we can give Doug something
> >useful, I suspect he'd try to use it.
> >
> >hansw wrote: Snip... home to opto
> >switches or promity detectors, not
> >Mechanical switches>
> >I measured <.003 per axis, havent
> >measured since. I'm changing the
> >workpiece every time anyway.
> >
> >Adding a line editor to CNCPro should be
> >simple; same to shell out to dos for
> >file transfers;
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 5
> > Date: Mon, 14 Feb 2000 10:58:26 -0500
> > From: Joe Vicars <jvicars@...>
> >Subject: encoders from servos?
> >
> >What is a quadrature encoder and how do I know if I have one?
> >I have a bunch of old servos and want to take the encoders off to make
> >Lindsay's DRO. Are these the encoders I need?
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 6
> > Date: Mon, 14 Feb 2000 11:07:04 -500
> > From: daveland@...
> >Subject: sis 530 Chipset MB
> >
> >Darrel
> >
> >I have had several SIS 530 Motherboards. All have worked
> >out great.
> >
> > But to get Xwindows working really well you need
> >the latest version of Xfee86 3.3.3.5 (I think). I downladed
> >it from redhat as RPM's ( 5-6MB). I can get the URL tonight when I get back
> >home. It was not easy to find. I can also email the xf86config file for my
> machine
> >that is running this server. But It was a pretty simple setup using the
> xconfigurator.
> > I'll
> >post and email late tonight.
> >
> >older versions can be fooled into working, but it isn't worth
> >the time.
> >
> >
> >dave
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 7
> > Date: Mon, 14 Feb 2000 08:07:24 -0800
> > From: Jon Anderson <janders@...>
> >Subject: Re: Re: CNCPro
> >
> >Roger,
> >
> >Yes, Ah-ha does radius comp. I can believe it can be problematic to
> >program.
> >I got up to the MaxNC version that had radius comp, and it often made
> >some really
> >strange moves while calling an offset.
> >My dad machines some highly abrasive stuff for a customer, on a Sherline
> >I CNC'd
> >for him. Radius comp is a must, to account for cutter wear and maintain
> >tolerances.
> >It's way too much of a pain generating 4-6 seperate G-code files with
> >differing offset
> >tool paths, then keeping track of them all.
> >I'd have liked to try his program, but I do understand where he's coming
> >from.
> >Lots of folks window shop and never buy, he's concentrating on
> >supporting those
> >that support him. That means he'll inplement radius comp sooner if
> >CNCPro users
> >start asking for it, over non-users.
> >
> >Jon
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 8
> > Date: Mon, 14 Feb 2000 11:47:07 EST
> > From: WAnliker@...
> >Subject: Re: Re: CNCPro
> >
> >In a message dated 2/14/00 9:15:14 AM Mountain Standard Time,
> >janders@... writes:
> >
> ><< That means he'll inplement radius comp sooner if
> > CNCPro users
> > start asking for it, over non-users.
> > >>
> >
> >But a lot of no-users will stay that way, until the program has radius
> >compensation.
> >The way to sell more programs is to have the features that will fill
> >non-users needs, then they will buy. Why would a non-user buy on the hopes
> >that someday the author MIGHT add the desired features?
> >bill
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 9
> > Date: Mon, 14 Feb 2000 11:54:58 -0600
> > From: Dan Falck <dfalck@...>
> >Subject: Re: Re: CNCPro
> >
> >EMC has cutter comping.
> >
> >Dan
> >
> >
> >
> >At 09:32 AM 2/14/2000 , you wrote:
> >>From: Roger Brower <rbrower@...>
> >>
> >>Jon Anderson Wrote:
> >>Snip...radius comp at that time wasn't
> >>as high on the list...
> >>
> >>Yeah, I'd love to have radius
> >>compensation in the controller, but
> >>that's apparently pretty hard to do,
> >>programming wise, with the lookahead
> >>function and all.
> >>I could be to blame! I probably told
> >>Doug I'd do that in the CAM step; Ahha
> >>has it? Does EMC do radius comp?
> >>reliably? Anybody know how to program
> >>it? If we can give Doug something
> >>useful, I suspect he'd try to use it.
> >>
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 10
> > Date: Mon, 14 Feb 2000 13:13:02 -0500
> > From: Jay Hayes <xmas4lites@...>
> >Subject: Re: CAM in Polar format
> >
> >Fred, what I'm trying to do is take a CAD drawing and create code that
> will output the length of the vector to one axis and the
> >relitive change in angle between that vector and the next vector in the
> chain to the second axis. Both axis will definately be
> >incrimental moves.
> >
> >Jay Hayes
> >Weston,WV
> >
> >Fred Smith wrote:
> >
> >> From: "Fred Smith" <imserv@...>
> >>
> >> > From: Jay Hayes <xmas4lites@...>
> >> >
> >> > I need to convert a simple 2D .dxf CAD drawing of a tool path to a
> >> > machine code in a Polar format, of the Vector distance and relative
> >> > angular Direction. I can manually write the code or manually extrapolate
> >> > the information from the verification functions in Bobcad, but i'm
> >> > looking to generate a post processed code automatically.
> >> >
> >>
> >> Tell us a little more Jay. It's not clear if you want to actually program
> >> in Polar coordinates, meaning R-Theta type annotation, or something else.
> >> What are you trying to program, what machine/control, are you sure you want
> >> Relative angular direction or Absolute? What is your orientation to the
> >> axes? Bobcad 17 has some very limited rotary translation capabilities and
> >> may be able to get the answers you need.
> >>
> >> Best Regards,
> >>
> >> Fred Smith
> >> IMService
> >>
> >> imserv@...
> >> Phone: 248-486-3600 or 800-386-1670
> >> Fax:248-486-3698
> >>
> >> --------------------------- ONElist Sponsor ----------------------------
> >>
> >> GET A NEXTCARD VISA, in 30 seconds. Get rates as low as 2.9 percent
> >> Intro or 9.9 percent Fixed APR and no hidden fees. Apply NOW.
> >> <a href=" http://clickme.onelist.com/ad/NextcardCreative4SR ">Click
> Here</a>
> >>
> >> ------------------------------------------------------------------------
> >>
> >> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the
> discussion of shop built systems in the above catagories.
> >> To Unsubscribe, read archives, change to or from digest.
> >> Go to: http://www.onelist.com/isregistered.cgi
> >> Log on, and you will go to Member Center, and you can make changes there.
> >> For the FAQ, go to http://www.ktmarketing.com/faq.html
> >> bill,
> >> List Manager
> >
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 11
> > Date: Mon, 14 Feb 2000 10:16:09 -0800
> > From: Jon Anderson <janders@...>
> >Subject: Re: Re: CNCPro
> >
> >Bill,
> >
> >You might have missed an earlier comment of mine. I asked Doug about
> >radius comp, saying neither my dad nor I would buy a program that
> >didn't have it, and wanted to know when it might be implemented.
> >His response was that he was concerned first with supporting existing
> >customers and their wants before spending resources adding features
> >for folks that hadn't bought the program. Radius comp at that time
> >wasn't
> >very close to the top. It was on the list at that time however.
> >I agree with you entirely regarding the added desireability of a greater
> >feature set. My point is that since he places more weight
> >on input from paid users, that's where the most effect pressure would
> >originate.
> >
> >Jon
> >
> >
> >WAnliker@... wrote:
> >
> >> But a lot of no-users will stay that way, until the program has radius
> >> compensation.
> >> The way to sell more programs is to have the features that will fill
> >> non-users needs, then they will buy. Why would a non-user buy on the hopes
> >> that someday the author MIGHT add the desired features?
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 12
> > Date: Mon, 14 Feb 2000 12:40:53 -0600
> > From: Jon Elson <jmelson@...>
> >Subject: Re: Re: CNCPro
> >
> >
> >
> >Roger Brower wrote:
> >
> >> From: Roger Brower <rbrower@...>
> >>
> >> Jon Anderson Wrote:
> >> Snip...radius comp at that time wasn't
> >> as high on the list...
> >>
> >> Yeah, I'd love to have radius
> >> compensation in the controller, but
> >> that's apparently pretty hard to do,
> >> programming wise, with the lookahead
> >> function and all.
> >> I could be to blame! I probably told
> >> Doug I'd do that in the CAM step; Ahha
> >> has it? Does EMC do radius comp?
> >> reliably?
> >
> >Absolutely! It works in all movement modes except G00, which
> >sort of makes sense. So, you can do linear, arc and helical
> >moves with radius comp. I have never had any trouble with
> >the radius comp, except getting the lead-in move to not
> >get a squawk about concave corners. This is a problem with
> >the way radius comp works, and I went through the same
> >trouble with the Allen-Bradley control I started with. EMC
> >is a bit more sensitive about these concave corners, but that
> >is not really EMC's fault. The 'backplotter' (on screen preview
> >of programmed moves) makes this a LOT easier and faster
> >to debug. I pretty much have this down solid, now. I did
> >some parts with radius comp this weekend, and it worked
> >flawlessly. I often use it so that I can use the same program
> >to make roughing cuts (with the tool diameter defined in the
> >tool table to be larger than the actual tool) and then make
> >a finishing cut with the tool table set to the actual tool size.
> >
> >> Anybody know how to program
> >> it? If we can give Doug something
> >> useful, I suspect he'd try to use it.
> >
> >Combining radius comp with alternating linear and arc cuts
> >and lookahead sounds pretty tough to me. I think I'd want
> >to spend a week at the blackboard with a colleague to bounce
> >all the possible cases off of before saying anything with
> >confidence.
> >
> >>
> >> hansw wrote: Snip... home to opto
> >> switches or promity detectors, not
> >> Mechanical switches>
> >> I measured <.003 per axis, havent
> >> measured since.
> >
> >When using home switches with shaft encoders that have the
> >index signal, the home switch just gets you to the right rotation
> >of the encoder, the index pulse sets the actual home position,
> >generally to one specific encoder count.
> >
> >Jon
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 13
> > Date: Mon, 14 Feb 2000 12:44:48 -0600
> > From: Jon Elson <jmelson@...>
> >Subject: Re: encoders from servos?
> >
> >
> >
> >Joe Vicars wrote:
> >
> >> From: Joe Vicars <jvicars@...>
> >>
> >> What is a quadrature encoder and how do I know if I have one?
> >> I have a bunch of old servos and want to take the encoders off to make
> >>
> >> Lindsay's DRO. Are these the encoders I need?
> >
> >If they are optical shaft encoders on servo motors, then they most
> >likely are
> >quadrature. Optical shaft encoders generally produce two signals with a
> >
> >90 degree phase relationship, so you can tell not only distance
> >traveled, but
> >direction as well. Many have a 3rd channel which produces one pulse per
> >
> >revolution, called the index pulse. For a servo motor application for
> >rotation
> >in only one direction, there might be only one pulse output signal.
> >
> >Other position readout types are rotary inductosyn and resolver. These
> >generally require interpolation to produce sufficient resolution for
> >machine
> >controls.
> >
> >Jon
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 14
> > Date: Mon, 14 Feb 2000 14:40:16 -0500
> > From: Brian Bartholomew <bb@...>
> >Subject: Re: BDI install disk for EMC -evidence that a braindead install
> already exists
> >
> >Patrick, please re-read the actual terms I proposed in my previous
> >postings. My offer was carefully designed NOT to have the obnoxious
> >properties you describe below. Your critique is responding to an
> >offer I didn't make.
> >
> >
> >A member of the League for Programming Freedom (LPF) http://lpf.ai.mit.edu
> >---------------------------------------------------------------------------
> ----
> >Brian Bartholomew - bb@... - www.wv.com - Working Version, Cambridge, MA
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 15
> > Date: Mon, 14 Feb 2000 12:16:45 -0800
> > From: "Darrell" <dgehlsen@...>
> >Subject: Re: Re: CNCPro
> >
> >> Roger,
> >>
> >> Yes, Ah-ha does radius comp. I can believe it can be problematic to
> >> program.
> >
> >AHHA has been doing Both diameter and tool lenght allowing either G43 or G44
> >for length. It works very well.
> >Darrell
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 16
> > Date: Mon, 14 Feb 2000 12:24:30 -0800
> > From: "Darrell" <dgehlsen@...>
> >Subject: Re: Re: CNCPro
> >
> >>> Does EMC do radius comp?
> >> > reliably?
> >>
> >> Absolutely! It works in all movement modes except G00, which
> >> sort of makes sense.
> >
> >Do you mean that if you turn on say G41 with a G00 move that you then have
> >to do a feed move before the tool is properly offset?
> >With AHHA, the tool is offset with a G00 G41 X Y move so you are ready to
> >plunge.
> >Darrell
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 17
> > Date: Mon, 14 Feb 2000 16:26:24 EST
> > From: WAnliker@...
> >Subject: Re: Re: CNCPro
> >
> >In a message dated 2/14/00 11:23:30 AM Mountain Standard Time,
> >janders@... writes:
> >
> ><< I agree with you entirely regarding the added desirability of a greater
> > feature set. My point is that since he places more weight
> > on input from paid users, that's where the most effect pressure would
> > originate. >>
> >
> >
> >
> >And this is why I made my comments, you would never go and buy a car with
> the
> >hopes that as an owner that you could lean on the manufacturer to include
> air
> >conditioning in the next model. The way to increase value is to add
> features
> >and get new buyers, they will furnish the new money needed to pay for the
> >design times.
> >I am still looking for a program to cut my teeth on, but with a retirement
> >income, want as much as I can get for the dollars spent. Unfortunately
> >Linux/EMC, has a bit more learning curve just trying to get it up and
> running
> >than I am able to handle with no programming experience. Linux, can
> probably
> >become a very great operating system, but not until it can be put into
> >operation, with a lot more ease than it is now able to, at least for an
> >individual that does not program.
> >thanks for your comments,
> >bill
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 18
> > Date: Mon, 14 Feb 2000 16:31:12 -0600
> > From: Jon Elson <jmelson@...>
> >Subject: Re: Re: CNCPro
> >
> >
> >
> >Darrell wrote:
> >
> >> From: "Darrell" <dgehlsen@...>
> >>
> >> >> Does EMC do radius comp?
> >> > > reliably?
> >> >
> >> > Absolutely! It works in all movement modes except G00, which
> >> > sort of makes sense.
> >>
> >> Do you mean that if you turn on say G41 with a G00 move that you then
> >> have
> >> to do a feed move before the tool is properly offset?
> >> With AHHA, the tool is offset with a G00 G41 X Y move so you are ready
> >> to
> >> plunge.
> >
> >No, I ran into this just this weekend. You get an error message that
> >says
> >rapid moves are not permitted with cutter diameter compensation active,
> >or
> >something of that nature. Not a big deal, you generally wouldn't want
> >to do
> >rapid feeds with diameter comp on, anyway. I hit the error because I
> >had a
> >G00 by accident as the move where the diameter comp was to be
> >interpolated
> >in. The first move when diameter comp is activated interpolates the
> >compensation
> >in gradually over the length of the move. My Allen-Bradley CNC did the
> >same,
> >so I think that is the normal mode.
> >
> >I generally plunge to depth BEFORE I activate the diameter comp, so that
> >the
> >tool plunges when NOT in contact with the work.
> >
> >This is totally different behavior than how the tool length offset works
> >(that's
> >G43, I think). With the length offset, it just fully activates the
> >offset immediately
> >on the first Z move.
> >
> >Jon
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 19
> > Date: Mon, 14 Feb 2000 16:14:44 -0600
> > From: hansw <hansw@...>
> >Subject: Re: Re: CNCPro
> >
> >Bill,
> >Well said.
> >
> >The main complaint I have heard about CNCPro is lack of "radius comp".
> >I think you should ask yourself, how much will you use it.
> >
> >Myself, I think I can say never. If a tool needs sharpening, I don't have
> the equipment to sharpen it, so I would
> >never have the need to compensate.
> >
> >If I needed to use a tool that was different from the one planned. Well I
> will simply redo the files to match the tool I do
> >have.
> >Which compensates very well for radius variations ! Becasue I car does not
> have a GPS built in does not mean I can't use
> >it, maps are wonderful things.
> >
> >As to Linux and EMC. Well I am a programmer, and must say this forum has
> been an eye opener about the mess Linux is in.
> >
> >Sure people manage to get it working, but the messages clearly show Linux
> is not for the faint of heart.
> >
> >I have a kind offer from someone to set up a drive with Linux, but I'm
> more and more inclined to forget it. I simply don't have
> >
> >the time, or want the hassles of it.
> >
> >CNCPro has other features I think EMC does not have at the moment, and may
> or may not have. At least CNCPro is supported by
> >a person that "gets hungry" and hunger is a darn good driving force....
> >
> >Hans Wedemeyer
> >
> >
> >WAnliker@... wrote:
> >
> >> From: WAnliker@...
> >>
> >> In a message dated 2/14/00 11:23:30 AM Mountain Standard Time,
> >> janders@... writes:
> >>
> >> << I agree with you entirely regarding the added desirability of a greater
> >> feature set. My point is that since he places more weight
> >> on input from paid users, that's where the most effect pressure would
> >> originate. >>
> >>
> >> And this is why I made my comments, you would never go and buy a car
> with the
> >> hopes that as an owner that you could lean on the manufacturer to
> include air
> >> conditioning in the next model. The way to increase value is to add
> features
> >> and get new buyers, they will furnish the new money needed to pay for the
> >> design times.
> >> I am still looking for a program to cut my teeth on, but with a retirement
> >> income, want as much as I can get for the dollars spent. Unfortunately
> >> Linux/EMC, has a bit more learning curve just trying to get it up and
> running
> >> than I am able to handle with no programming experience. Linux, can
> probably
> >> become a very great operating system, but not until it can be put into
> >> operation, with a lot more ease than it is now able to, at least for an
> >> individual that does not program.
> >> thanks for your comments,
> >> bill
> >>
> >> --------------------------- ONElist Sponsor ----------------------------
> >>
> >> FREE ADVICE FROM REAL PEOPLE! Xpertsite has thousands of experts who
> >> are willing to answer your questions for FREE. Go to Xpertsite today
> >> and put your mind to rest.
> >> <a href=" http://clickme.onelist.com/ad/XpersiteCPC ">Click Here</a>
> >>
> >> ------------------------------------------------------------------------
> >>
> >> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the
> discussion of shop built systems in the above catagories.
> >> To Unsubscribe, read archives, change to or from digest.
> >> Go to: http://www.onelist.com/isregistered.cgi
> >> Log on, and you will go to Member Center, and you can make changes there.
> >> For the FAQ, go to http://www.ktmarketing.com/faq.html
> >> bill,
> >> List Manager
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 20
> > Date: Mon, 14 Feb 2000 16:53:11 -0700
> > From: Greg Nuspel <gregnuspel@...>
> >Subject: Tool radius compensation
> >
> >On thing about tool radius compensation is that it allows you to program
> >in the part profile with no further calculation.
> >
> >--
> >Greg Nuspel
> >
> >"Make everything as simple as possible, but not simpler. "
> > - Albert Einstein (1879-1955)
> >
> >http://members.home.net/gregsdiversions
> >ICQ 13585790
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 21
> > Date: Mon, 14 Feb 2000 18:57:00 -0500 (EST)
> > From: stratton@...
> >Subject: Re: encoders from servos?
> >
> >> From: Joe Vicars <jvicars@...>
> >>
> >> What is a quadrature encoder and how do I know if I have one?
> >> I have a bunch of old servos and want to take the encoders off to make
> >> Lindsay's DRO. Are these the encoders I need?
> >>
> >
> >If you are by chance talking about radio control model servos, then
> >the answer is no (those are simple variable resistors).
> >
> >If you mean large servomotors designed for machine tools or similar
> >applications then yes, there is a good chance they might work. On the
> >other hand, perhaps you could use the servos AND the encoders to CNC
> >your machine tool.
> >
> >Chris
> >
> >--
> >Christopher C. Stratton, stratton@...
> >Instrument Maker, Horn Player & Engineer
> >30 Griswold Street, Cambridge, MA 02138
> >http://www.mdc.net/~stratton
> >(617) 492-3358 home/shop
> >
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 22
> > Date: Mon, 14 Feb 2000 19:17:34 -0500
> > From: "Fred Smith" <imserv@...>
> >Subject: Re: Re: CNCPro
> >
> >>
> >> Myself, I think I can say never. If a tool needs sharpening, I don't have
> >the equipment to sharpen it, so I would
> >> never have the need to compensate.
> >>
> >never say never ;-)
> >
> >The main reason for cutter comp is not tool wear & the use of tooling that
> >is different from that which was used in the program. The primary reason is
> >to hold tight tolerances. If for instance you had to mill a slot that had a
> >+/-.002 inch tolerance. You would be able to cut this by programming with
> >offset curves in a Bobcad or Vector type of application. The usual way
> >would be to program the offset curve just larger than the tool radius,
> >measure the resulting size, then *reprogram* the part with the difference
> >between the desired size & that actually cut. The reprogramming would
> >involve drawing another offset curve & regenerating the portion of the
> >program involved with the slot.
> >
> >With cutter comp capability, (G41/G42) The tool radius offset would be
> >changed from +.002 to whatever adjustment was needed to bring the slot to
> >size, then the same tested program would be rerun. While it is quite easy
> >to regenerate the entire program, and it will make as accurate of a part,
> >the chances for error are much greater when using an untested program or
> >even a regenerated one, vs just re-running one that you have already tested
> >out.
> >
> >It is very easy to control turning on and off of cutter comp, by using the
> >approach and depart function. This generates a teardrop shaped construction
> >that allows a beginning straight move during which you turn cutter comp on,
> >and a corresponding straight ending move, during which you turn cutter comp
> >off. Bobcad allows you to do this manually, and Vector automates the
> >process.
> >
> >
> >Best Regards,
> >
> >Fred Smith
> >IMService
> >
> >imserv@...
> >Phone: 248-486-3600 or 800-386-1670
> >Fax:248-486-3698
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >Message: 23
> > Date: Tue, 15 Feb 2000 00:39:20 -0600
> > From: Jon Elson <jmelson@...>
> >Subject: Re: Re: CNCPro
> >
> >
> >
> >Fred Smith wrote:
> >
> >> From: "Fred Smith" <imserv@...>
> >>
> >> >
> >> > Myself, I think I can say never. If a tool needs sharpening, I don't
> >> have
> >> the equipment to sharpen it, so I would
> >> > never have the need to compensate.
> >> >
> >> never say never ;-)
> >>
> >> The main reason for cutter comp is not tool wear & the use of tooling
> >> that
> >> is different from that which was used in the program. The primary
> >> reason is
> >> to hold tight tolerances. If for instance you had to mill a slot that
> >> had a
> >> +/-.002 inch tolerance. You would be able to cut this by programming
> >> with
> >> offset curves in a Bobcad or Vector type of application. The usual
> >> way
> >> would be to program the offset curve just larger than the tool radius,
> >>
> >> measure the resulting size, then *reprogram* the part with the
> >> difference
> >> between the desired size & that actually cut. The reprogramming would
> >>
> >> involve drawing another offset curve & regenerating the portion of the
> >>
> >> program involved with the slot.
> >
> >Right, you can compensate for tool deflection. I also find that cut
> >rate
> >end mills are not exactly on size. Many of them vary up to -.003" or
> >so. Another reason I use it is to make one program, either manually or
> >with a CAD/CAM package, and use it both for roughing and finishing
> >the part. I enter a cutter diameter larger than the actual tool size,
> >which
> >causes the CNC control to offset the tool farther from the part than the
> >
> >radius of the actual tool. This makes the roughing cut, leaving maybe
> >.010" on the side of the part. Then, I make several passes, stepping
> >the
> >depth down each time. Finally, I set the tool table to the actual size
> >of the tool, and run the program again, milling the sides to the exact
> >dimensions.
> >
> >Jon
> >
> >
> >
> >___________________________________________________________________________
> ____
> >___________________________________________________________________________
> ____
> >
> >
> >
> >
>
> --------------------------- ONElist Sponsor ----------------------------
>
> FREE ADVICE FROM REAL PEOPLE! Xpertsite has thousands of experts who
> are willing to answer your questions for FREE. Go to Xpertsite today
> and put your mind to rest.
> <a href=" http://clickme.onelist.com/ad/XpersiteCPC ">Click Here</a>
>
> ------------------------------------------------------------------------
>
> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the discussion of shop built systems in the above catagories.
> To Unsubscribe, read archives, change to or from digest.
> Go to: http://www.onelist.com/isregistered.cgi
> Log on, and you will go to Member Center, and you can make changes there.
> For the FAQ, go to http://www.ktmarketing.com/faq.html
> bill,
> List Manager