On Wed, 2017-02-22 at 08:14 -0500, Gene Heskett wrote: > On Wednesday 22 February 2017 04:50:20 Valerio Bellizzomi wrote: > > > > > Haveing a module processing data from a read above the actual port > > > read inserts a one loop execution delay in processing that data, so > > > unless you want a delay on purpose, the order is always the read at > > > the top of the list, the data massaging in the middle, and the write > > > of that data is always last in the addf order. The data twiddling > > > can be a thousand lines below all this, but it will be executed in > > > the order of the addf's. Delays in processing, then making use of > > > that data affects the stability of the loop because the data is > > > stale. Most noticeable when setting up the PID modules. > > > > Thanks Gene for this clarification about LinuxCNC internals > > You're most welcome. > > [...] > > > I'm not accustomed to inches, that should be 40 * 2.54 = 101.6 mm/min > > Wrong multiplier, an inch is 25.4 mm's, so 75 ipm=1905mm/minute, almost 2 > meters a minute. With the right motor instead of this 1600 oz clunker > I'm useing, I could at least double that.
That's true, oops, but well, yes the max speed is approx 2000mm/min > > with my current machine I can set a speed of up to 800mm/min (when > > cutting wood) without any problem > > Thats about 31.5"/minute. None of my spindles can cut mahogany at more > than 15"/minute, the spindle is way to slow, and then, since its > generally 3/4 inches thick wood, I do it in 3 passes to full depth. I > am fond of the Green and Green joint, a huge box joint whose fingers are > somewhere between 22 and and 28mm's wide, for furniture, and make it on > the G0704, including the assembly screw holes and the square pockets > above those for the ebony buttons that hide the screws. I make those on > the milling machine too. > > But the top speed on its spindle is around 2750 with the cheap bearings > in the back gearing screaming for mercy. I've got to replace them with > quality bearings. I don't often run it above 1500 in deference to those > cheap bearings. > > Where on this ball of rock and water are you? > > Cheers Valerio Bellizzomi, Gene Heskett > > > Cheers, Gene Heskett I can cut wood at 20mm depth at 300 to 500 mm/min but the vfd on my pantograph has a manual dial and a Hertz display, so I don't know the rpm for sure, only the frequency is displayed which I don't remember now ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
