I just pushed some commits to this branch that implement a crude error
message:

https://github.com/robEllenberg/linuxcnc-mirror/tree/feature/nominal-vel-during-sync

I also opened an issue for this:

https://github.com/LinuxCNC/linuxcnc/issues/167

-Rob

On Fri, Sep 30, 2016 at 12:20 AM Robert Ellenberg <[email protected]> wrote:

> That's a good point, it's not a perfect solution. At least in the case you
> describe, it wouldn't be any worse than today. The spindle speed command
> would be ignored, the user would get a warning, and the motion would keep
> going.
>
> That to me a is a good reason to make this an interpreter error, so the
> user gets some advance notice. By the time the motion starts, it could be
> too late to save the thread.
>
> Rob
>
> On Thu, Sep 29, 2016, 11:32 AM Gene Heskett <[email protected]> wrote:
>
> On Thursday 29 September 2016 08:49:50 John Kasunich wrote:
>
> > On Wed, Sep 28, 2016, at 09:35 PM, Robert Ellenberg wrote:
> > > That would certainly be convenient. What if we took it one step
> > > further and automatically limit the maximum spindle speed for each
> > > G33 segment? It would be ugly, but we may be able to stuff a spindle
> > > speed command into the queue before adding the line segment.
> > > Combined with a message to the user than this is occurring, it would
> > > be both safe and convenient for the user.
> >
> > That assumes that the machine has active control over the spindle
> > speed. Which is NOT necessary for threading and other G33 work.
> >
> > For example, my lathe has 16 spindle speeds which are determined by
> > how you set the belts on the pulleys.  The S-word has absolutely no
> > effect on the speed.  It doesn't matter whether you write M3S100 or
> > M3S10000, the spindle is going to start and run at the speed
> > determined by the belts.
> >
> > The spindle encoder tells LinuxCNC how fast the spindle is going and
> > thus allows for synchronized moves, but:
> >
> > 1) LinuxCNC can't change the speed if it doesn't like it
> > 2) LinuxCNC doesn't know the speed at the interp level, because the
> > S-word means nothing.  Only the encoder feedback can tell it the
> > spindle speed.
>
> I'll be in somewhat better shape with this Sheldon conversion John.
> Sure, mechanically I'll have the same old 8 speed spindle, backgear
> in/out plus 4 positions of the belt, but I'll also have a vfd running
> the 1 hp motor, replaceing its original 3/4 hp which had been fitted
> with a reverseing switch, which I'll likely have programmed for a 1/2 to
> 2 or 3x nameplate speed, so I'll have an ability to make use of such a
> feature.
>
> And depending on how fast the vfd can reverse it safely, G33.1 rigid
> tapping seems do-able.  Much better if I can start a tap drill for say a
> 1/4" bolt, centered on the mating face of the chucks backplate and the
> flange of the spindle it seats on, drill so half the hole is in the
> backplate and half in the spindle flange and tap the hole & put a bolt
> in it to lock the chuck so it can't be unscrewed by a quick reverse. I
> had to do that to the motor in TLM as the flywheel/fan/pulley is screwed
> to the motor shaft. I put 2 such bolts in it, 180 degrees apart. 1st
> mptor I used a 10-24 set screw, wrecked/crushed it and the shaft so the
> 2nd motor has 2 solid bolts in it.  Hasn't come loose yet. I've also put
> some ramping in the hal file to make the reversal a bit less violent.
>
> That limits the spindle speed for a g33.1 on TLM, but not from Z speed
> limits, but from turnaround overshoots, about 2.5 turns at 200 rpms in
> high gear, 4 or so turns in low gear because of the heavy motor
> flywheel. I've some hal stuff I can watch with a halmeter to tell me how
> many encoder counts this overshoot is so I can start the turnaround
> early enough I don't slip the tap or break it against the bottom of a
> blind hole.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page <http://geneslinuxbox.net:6309/gene>
>
>
> ------------------------------------------------------------------------------
> _______________________________________________
> Emc-developers mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/emc-developers
>
>
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most 
engaging tech sites, SlashDot.org! http://sdm.link/slashdot
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers

Reply via email to