Re: [Emc-users] Switches for home, limits
On 30 July 2015 at 12:20, Gene Heskett ghesk...@wdtv.com wrote: http://www.ebay.co.uk/itm/190836819378 These need at least 12 volts and 10 ma to function. I assume you use them as NC, opening when the hole is under the face? This would need some sort of a logic combiner unless quite a few pins are dedicated on the P2 plug of a 5i25 Mine run from 12V and are interfaced via a 7i64 smart-serial board. However I have a feeling that the NPN type can be powered from 12V with the output connected directly to a 5V input pin. But I would definitely wait for confirmation of that from PCW. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On 30 July 2015 at 12:52, andy pugh bodge...@gmail.com wrote: There are high-precision switches (1 um repeatability, 10um deviation after 1,000,000 cycles) but they don't come cheap ($100) http://www.ia.omron.com/product/item/d5a_1100f/ They do an optical version too. I doubt they sell many: http://uk.rs-online.com/web/p/safety-rated-interlock-switches/8411455/ -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 07:03:29 John Alexander Stewart wrote: Gene: I used (for better or worse) microswitches. X axis - you can see it to the left of one of the pics. Uses the original table stop and some of the screws that were in the table (for locking handles? can't remember off hand) http://cnc-for-model-engineers.blogspot.ca/2015/04/g0704-and-cnc-conve rsion-kit-last.html The Z and Y axis: http://cnc-for-model-engineers.blogspot.ca/2014/09/the-new-cnc-mill-kc 20vsbf20g0704-part-3.html John. The no longer required manual locks reminder gives me some additional freedom as that had not occured to me. What had occured was how do I keep them from being demolished if not correctly positioned? So that opens up additional possibilities, thanks John. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 07:28:16 Roland Jollivet wrote: If you're going to use micro-switches, rather use this http://uk.rs-online.com/web/p/microswitches/1031645/?searchTerm=103-1 645relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D6265724D 504E266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B337D5B5C732D2F2 55C2E2C5D5C647B332C347D2426706F3D313426736E3D592673743D52535F53544F434B 5F4E554D4245522677633D4E4F4E45267573743D3130332D3136343526 type; Notice how the button is almost directly under the roller, as opposed to the 'normal' type of being near the lever pivot. The indicated type will have increased switching sensitivity and lower hysteresis. Regards Roland Yes, thats a much better design. My x on the lathe was a button only since the crossfeed is a direct push, subminiature version of that. With the swarf brushed or blown away, repeatability is well under a thou. On 30 July 2015 at 13:02, Gene Heskett ghesk...@wdtv.com wrote: On Thursday 30 July 2015 03:02:45 Marcus Bowman wrote: On 30 Jul 2015, at 03:51, Gene Heskett wrote: I bought a bag of small, roller tipped microswitches, and have a couple mounts laid out but not carved yet. Going thru searches on ebay just now, for both inductive, capacitative, and IR proximity switches, It sees like the majority of them are needing 6 volts or more, and around 300 ma each to function. Having seen some micropower capacitative switches in the textbooks of yore, it seems like the ball has been dropped in terms of being useful in a 5 volt logic circuit. Both the microswitch, and the inductive versions would seem to be sensitive to collecting swarf, particularly if its a rare earth magnet running a reed switch. My lathe seems to be relatively happy with a microswitch located under the back edge of the bed for Z homing where swarf tends to fall on past it, but x has to be kept swept clean because its actually on top of the carriage. I see a whole passel of stuff drilled onto GO704's in the hits I can get from google, but all of them preclude retaining the rubber swarf shields, which I'd say was not worth the tradeoff. There has to be a better way. So what sort of switches, and what swarf shielding to keep them relatively clean accurate are others using? PM's with pix appreciated if you have the time. Actually, this is a really interesting question. Having spent ages thinking about shielded locations for the mill, and about to do the same for the lathe, it would be useful if folks could put the pictures somewhere we could all see them. If anyone has any recommendations about makes and models of switches/sensors which provide better accuracy and repeatability than others, or useful ways of providing adjustment on mounting arrangements, that would also be very useful. Marcus My thoughts exactly Marcus. In my googling, something like 3/4ths of the sites that may have had helpful pictures, were behind a login requester. Since I am not a member of any of those Mach oriented groups, thats less than helpful. For X, I have considered removing the pointer which is also a mechanical limit stop, and likely demolishable to an out of control move as there are a couple OEM stoppers that would hit it. Once removed, then move one of the stopper knobs (they are in a 'T' slot in the front edge of the table) to someplace near the center of the table, and mount a switch that it would close on the way by which would function as the home switch. A similar setup is now on my lathe, with the switch under the back rail of what passes for a bed, located to be activated when no tool holder is mounted, and only 3/4 or so from the chuck face. X has already been homed and parked about 1mm from its outside limit. Having both switches well off center moderately well precludes its looking for the switch in the wrong direction as its z is normally parked well away from the work for gauge etc checking access to whats in the chuck. So this has worked well for a year for me. But I see no way to make certain that it looks in the right direction to find home on a mill without physically locating the switch well away from the center of the table. eg the switches trip point will need to be toward the end of the travel, and a HOME_OFFSET then used to put zero back at the center. From there, soft limits + - would be used in place of the existing knobs hitting the heavy centrally located pointer. There are not currently available, any such Y stops, so all of that will have to be imagined and built. Again, off center far enough that from any usual powerup location that it will search in the correct direction to find the switch, then a HOME-OFFSET that establishes a zero on the dro's at the center of travel, and again setting software limits from this
Re: [Emc-users] Switches for home, limits
There are high-precision switches (1 um repeatability, 10um deviation after 1,000,000 cycles) but they don't come cheap ($100) http://www.ia.omron.com/product/item/d5a_1100f/ -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On Wed, Jul 29, 2015, at 09:35 PM, richsh...@comcast.net wrote: I am adapting a version of the little hobber and want to use linux-CNC to do the ratio division between the hob and the work spindles. Additionally, a third axis that is actually the feed needs to be incorporated. Any thoughts. The encoder-ratio HAL component was invented with this specific use in mind. http://linuxcnc.org/docs/html/man/man9/encoder_ratio.9.html It is a software based encoder counter (like the regular software encoder counter), but it does the math differently to avoid some problems that can happen if you use a more normal approach. The normal approach would be to use either software or hardware encoder counters to measure the position of each axis, then scale the positions based on the tooth ratios, and eventually compare them to determine how to drive the slave axis. The problem is that if you run long enough you start running out of accuracy. Imagine that your hobber has been running for hours. You might find yourself subtracting 100,000,000.03 revolutions of the master from 100,000,000.05 revolutions of the slave. If the math doesn't have enough significant digits, the 0.02 revolution difference gets lost in the noise. The encoder ratio component uses a different approach to the math, and will never run out of accuracy no matter how long it goes. -- John Kasunich jmkasun...@fastmail.fm -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
Gene; The no longer required manual locks reminder gives me some additional freedom as that had not occured to me. What had occured was how do I keep them from being demolished if not correctly positioned? So that opens up additional possibilities, thanks John. The X axis on mine; I retain one of the round table stops in that front of table dovetail that you mention in a previous email. The microswitch is positioned on a front plate, spacers and M6 bolts to pre-existing holes. Microswitch is horizontal so that (in theory, anyway) the table stop will not crash into and destroy the switch. I removed the front measuring tape, and on my front plate, I machined up some long rectangular bars from scrap that are bolted to the front plate, but ride in the slot where the measuring tape was; the fit is pretty close, so the chance of swarf getting onto the microswitch is pretty small. The Y axis - I machined a flat on the base casting, with a bunch of tapped holes, so the Y axis switch base is just a bit of angle. Again, an existing locking handle hole on the saddle casting is used for the trigger. The Y axis switch is covered with a metal cover machined from something from my scrap box (an old hammond box) such that the microswitch is covered; the base angle under the roller machined away such that if any swarf does indeed find its way in, hopefully gravity will help it find its way out. It is also under the table, so I don't expect too much swarf to get in. The only issue that I have with the Y is that there is a potential interference with the right hand bracket for the X axis; one of these days I'll take a file to the bracket so that I can get the full table travel without the possibility of interference. Hope this helps - John. -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 07:52:31 andy pugh wrote: There are high-precision switches (1 um repeatability, 10um deviation after 1,000,000 cycles) but they don't come cheap ($100) http://www.ia.omron.com/product/item/d5a_1100f/ Amazing. I didn't think Omron made anything of that quality. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
I guess you have start calculation from the encoder counters each time and then there will be no problem with add up over time. Nicklas Karlsson On Thu, 30 Jul 2015 09:44:02 -0400 John Kasunich jmkasun...@fastmail.fm wrote: On Wed, Jul 29, 2015, at 09:35 PM, richsh...@comcast.net wrote: I am adapting a version of the little hobber and want to use linux-CNC to do the ratio division between the hob and the work spindles. Additionally, a third axis that is actually the feed needs to be incorporated. Any thoughts. The encoder-ratio HAL component was invented with this specific use in mind. http://linuxcnc.org/docs/html/man/man9/encoder_ratio.9.html It is a software based encoder counter (like the regular software encoder counter), but it does the math differently to avoid some problems that can happen if you use a more normal approach. The normal approach would be to use either software or hardware encoder counters to measure the position of each axis, then scale the positions based on the tooth ratios, and eventually compare them to determine how to drive the slave axis. The problem is that if you run long enough you start running out of accuracy. Imagine that your hobber has been running for hours. You might find yourself subtracting 100,000,000.03 revolutions of the master from 100,000,000.05 revolutions of the slave. If the math doesn't have enough significant digits, the 0.02 revolution difference gets lost in the noise. The encoder ratio component uses a different approach to the math, and will never run out of accuracy no matter how long it goes. -- John Kasunich jmkasun...@fastmail.fm -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 08:50:22 John Alexander Stewart wrote: Gene; The no longer required manual locks reminder gives me some additional freedom as that had not occured to me. What had occured was how do I keep them from being demolished if not correctly positioned? So that opens up additional possibilities, thanks John. The X axis on mine; I retain one of the round table stops in that front of table dovetail that you mention in a previous email. I can see that in the pix. The microswitch is positioned on a front plate, spacers and M6 bolts to pre-existing holes. Microswitch is horizontal so that (in theory, anyway) the table stop will not crash into and destroy the switch. I am assuming the knob can ride over and pass by the switch w/o damaging it. That would seem to be a requirment so that full use of the table can be had. I removed the front measuring tape, and on my front plate, I machined up some long rectangular bars from scrap that are bolted to the front plate, but ride in the slot where the measuring tape was; the fit is pretty close, so the chance of swarf getting onto the microswitch is pretty small. Great idea. The Y axis - I machined a flat on the base casting, with a bunch of tapped holes, so the Y axis switch base is just a bit of angle. Again, an existing locking handle hole on the saddle casting is used for the trigger. The Y axis switch is covered with a metal cover machined from something from my scrap box (an old hammond box) such that the microswitch is covered; the base angle under the roller machined away such that if any swarf does indeed find its way in, hopefully gravity will help it find its way out. It is also under the table, so I don't expect too much swarf to get in. Only that which we blow in with an air hose while clearing the tabletop so a vice or rotary sits clean level. :) The only issue that I have with the Y is that there is a potential interference with the right hand bracket for the X axis; one of these days I'll take a file to the bracket so that I can get the full table travel without the possibility of interference. I don't recall that on mine, the X motor is on the left end of the table. Only the ball screws thrust bearing is on the right and that isn't a huge hangy down. I am thinking of a switch laying horizontally, roller to face left, with a round headed screw in a lock lever hole that will trigger it, but ride right on by in normal operation. There should be room enough under the X that the switch can be mounted under the lip of a piece of 3/4 x 1/16th alu angle to servo as a swarf roof Far enough fwd that it should clear the X thrust bearing bulge. Homing Z up out of the way seems like it ought to be #0 in the HOME_SEQUENCE. At one point while working on the spindle encoder I needed to drill tap some 3mm holes had to invent a long handled tap that I could work right beside the spindle motor, so I drove the square end of the tap into a 12 piece of a suitable sized brass pipe from the model shop. Worked a treat. Its going to be stuck there till whenever as its handier than a button on the outhouse door to just chuck it up in a 20 volt drill. I think it will get used several times in mounting all this. Some good ideas are materializing here John, thanks. I had taken a nap after the earlier postings, and just woke up again. :) Someones Z stuff on the post will be first, so I can code it it order in the hal ini files. X is in plain sight last. Off to the shop the toy mill to make some of this. No AC in the shop its already right at 80F locally, with humidity to match. I call that Mugly out. Thanks. Hope this helps - John. -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
John that same counting cleverness needs to be in or merged with the differential for helical gears to allow it all to remain in gear and have a fine feed and to move the cutter head back to be able to measure and take another shaving. http://www.collection.archivist.info/hobbing.html having used the hal method I did get a slight error http://www.collection.archivist.info/searchv13.php?searchstr=speedo pics at bottom show a slight helix I did add encoders to the machine to see if there was any slip/step loss/other bugs but did not find the error, being small when sliced into gears it remains as a feature. Dave Caroline On 30/07/2015, John Kasunich jmkasun...@fastmail.fm wrote: On Wed, Jul 29, 2015, at 09:35 PM, richsh...@comcast.net wrote: I am adapting a version of the little hobber and want to use linux-CNC to do the ratio division between the hob and the work spindles. Additionally, a third axis that is actually the feed needs to be incorporated. Any thoughts. The encoder-ratio HAL component was invented with this specific use in mind. http://linuxcnc.org/docs/html/man/man9/encoder_ratio.9.html It is a software based encoder counter (like the regular software encoder counter), but it does the math differently to avoid some problems that can happen if you use a more normal approach. The normal approach would be to use either software or hardware encoder counters to measure the position of each axis, then scale the positions based on the tooth ratios, and eventually compare them to determine how to drive the slave axis. The problem is that if you run long enough you start running out of accuracy. Imagine that your hobber has been running for hours. You might find yourself subtracting 100,000,000.03 revolutions of the master from 100,000,000.05 revolutions of the slave. If the math doesn't have enough significant digits, the 0.02 revolution difference gets lost in the noise. The encoder ratio component uses a different approach to the math, and will never run out of accuracy no matter how long it goes. -- John Kasunich jmkasun...@fastmail.fm -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On 30 July 2015 at 15:23, Karlsson Wang nicklas.karls...@karlssonwang.se wrote: I guess you have start calculation from the encoder counters each time and then there will be no problem with add up over time. There is a danger of encoder counters rolling over the signed-32 HAL pin value. (though the counter are internally promoted to 64 bits in all the LinuxCNC counters). Unfortunately the encoder_ratio is not applicable to Mesa / Pico / General Mechatronics / Pluto hardware counters. My hobber uses the floating point position values. There is a danger of loss of precision after many revolutions with this approach, but no risk of rollover-based problems. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Possible lathe spindle encoder.
Has anyone found a source for the ATS694? Digikey doesn't have a listing... -Original Message- From: andy pugh [mailto:bodge...@gmail.com] Sent: Wednesday, July 29, 2015 3:38 PM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] Possible lathe spindle encoder. A useful allegro publication, google for AN296089 (I can't seem to get a link out of google) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
I've had an idea for a while that an old brake disc lathe would make a good base for a gear hobbing machine. It has a strong spindle where the disc mounts to fit the hob, and a slide at 90 degrees to it where a second spindle holding the gear blank could be mounted. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 08:50:22 John Alexander Stewart wrote: Gene; The no longer required manual locks reminder gives me some additional freedom as that had not occured to me. What had occured was how do I keep them from being demolished if not correctly positioned? So that opens up additional possibilities, thanks John. The X axis on mine; I retain one of the round table stops in that front of table dovetail that you mention in a previous email. The microswitch is positioned on a front plate, spacers and M6 bolts to pre-existing holes. Microswitch is horizontal so that (in theory, anyway) the table stop will not crash into and destroy the switch. I removed the front measuring tape, and on my front plate, I machined up some long rectangular bars from scrap that are bolted to the front plate, but ride in the slot where the measuring tape was; the fit is pretty close, so the chance of swarf getting onto the microswitch is pretty small. That is what I will do also, but haven't gotten that far today, figured I'd do the Z first, which is on, programmed and working. Then I took one of the X buttons, added a spacer washer behind it and installed it in the front Y lock bolt hole. Spacer needed to put the button out far enough to hit the switchs roller since its forcibly spaced out by the switch mounting bolts being in firm contact with the slanted side of the base. Then took a 4.5 piece of 1x1/8th flat alu, and bent both ends so the bottom could be bolted to a tapped hole I made in the top of the base flat. Its bent inward at about the same angle as the base casting, then bent to come straight up at about 1.5 off the top of the base. Slotted to mount one of those microswitches on the face toward the Y carriage. But I miss-judged how far fwd that x button will come, so now I need to reverse the switch putting its roller about an inch farther back, and of course drill tap another 3m hole in the base so its solidly mounted. It sure seems to be solid even with only one 3mm cap screw it it ATM. And the X tables movements will never touch it. Then Dee came out asked if I was going to feed her, so we packed up took the toy out and found a nose bag with 2 big hunks of cod in it for me a special hamburger/fries for Dee, at a little greasy spoon about 10 miles west of Weston. That was my mistake, I sat down. And thats it for the day, my back started yelling the instant I got up to go pay the ransom. Tomorrow is another day to finish that, and get started on the X switch. I am pleased with progress so far The Y axis - I machined a flat on the base casting, with a bunch of tapped holes, so the Y axis switch base is just a bit of angle. Again, an existing locking handle hole on the saddle casting is used for the trigger. The Y axis switch is covered with a metal cover machined from something from my scrap box (an old hammond box) such that the microswitch is covered; the base angle under the roller machined away such that if any swarf does indeed find its way in, hopefully gravity will help it find its way out. It is also under the table, so I don't expect too much swarf to get in. The only issue that I have with the Y is that there is a potential interference with the right hand bracket for the X axis; one of these days I'll take a file to the bracket so that I can get the full table travel without the possibility of interference. Hope this helps - John. It does John, give me motivation to get to it. Thanks. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On 30 Jul 2015, at 03:51, Gene Heskett wrote: I bought a bag of small, roller tipped microswitches, and have a couple mounts laid out but not carved yet. Going thru searches on ebay just now, for both inductive, capacitative, and IR proximity switches, It sees like the majority of them are needing 6 volts or more, and around 300 ma each to function. Having seen some micropower capacitative switches in the textbooks of yore, it seems like the ball has been dropped in terms of being useful in a 5 volt logic circuit. Both the microswitch, and the inductive versions would seem to be sensitive to collecting swarf, particularly if its a rare earth magnet running a reed switch. My lathe seems to be relatively happy with a microswitch located under the back edge of the bed for Z homing where swarf tends to fall on past it, but x has to be kept swept clean because its actually on top of the carriage. I see a whole passel of stuff drilled onto GO704's in the hits I can get from google, but all of them preclude retaining the rubber swarf shields, which I'd say was not worth the tradeoff. There has to be a better way. So what sort of switches, and what swarf shielding to keep them relatively clean accurate are others using? PM's with pix appreciated if you have the time. Actually, this is a really interesting question. Having spent ages thinking about shielded locations for the mill, and about to do the same for the lathe, it would be useful if folks could put the pictures somewhere we could all see them. If anyone has any recommendations about makes and models of switches/sensors which provide better accuracy and repeatability than others, or useful ways of providing adjustment on mounting arrangements, that would also be very useful. Marcus Thanks. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Before i go bonkers: M98, M99
This is interesting. I've seen this sort of thing on other email lists and thought it was some sort of spam or some type of malware. Now I understand it's just a mistake. I never thought of this possibility! Very interesting what we can do with our butts. George R. On 7/29/2015 5:16 PM, Robert Ellenberg wrote: Sorry folks, it looks like I managed to butt-dial an email during my commute this morning. Crisis averted :) Rob On Jul 29, 2015 11:25, Gene Heskett ghesk...@wdtv.com wrote: On Wednesday 29 July 2015 10:25:39 Pete Matos wrote: Hehehe. What? Pete On Wednesday, July 29, 2015, Bertho Stultiens ber...@vagrearg.org wrote: On 07/29/2015 01:07 PM, Robert Ellenberg wrote: Pompeo Kirkman kiosk I kid in ipm Kiki Kokomo Kiki I ijkukKokomo Kiki Kik Kiki the I just just my Jim kipm I kill Kokomo Kiki kiosk imp the MIkkujkujk hiking j imitation I K my I I'm K kk I am KikiI I I ikkjiiujklukk Kiki nonono iok Kiki just as I joined Kids I my K my Catnip spilled on the keyboard? Kiki I'm knickknacks Kiki ikkji Calling section five, prepare for incoming. Make room for emergency transport. -- Greetings Bertho (disclaimers are disclaimed) -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net javascript:; https://lists.sourceforge.net/lists/listinfo/emc-users 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
Andy has implemented it on a mill http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Hobbing And I used the ideas from that page and did a stepper version on an old mill for someone and also an old hobbing machine made by Barber Colman http://www.collection.archivist.info/searchv13.php?searchstr=barber+colman and http://www.archivist.info/cnc/hob2/ there are some more thoughts I wrote up some years ago http://www.collection.archivist.info/hobbing.html in that diagram there is a differential, a hal comp has recently been implemented so that is now possible Dave Caroline On 30/07/2015, richsh...@comcast.net richsh...@comcast.net wrote: I am adapting a version of the little hobber and want to use linux-CNC to do the ratio division between the hob and the work spindles. Additionally, a third axis that is actually the feed needs to be incorporated. Any thoughts. -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On Thu, Jul 30, 2015, at 10:36 AM, Dave Caroline wrote: John that same counting cleverness needs to be in or merged with the differential for helical gears to allow it all to remain in gear and have a fine feed and to move the cutter head back to be able to measure and take another shaving. The output of the encoder-ratio component is a float value indicating the angular offset between the slave and the master. The assumption is that a PID loop would be used to control the slave and drive that offset to zero. You could add an intentional offset to the encoder-ratio output before the PID. The intentional offset could vary as the hob moves across the gear face to make helical gears, or have small steps added/subtracted to shave the leading or trailing face of the teeth. -- John Kasunich jmkasun...@fastmail.fm -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On Thu, Jul 30, 2015, at 10:33 AM, andy pugh wrote: On 30 July 2015 at 15:23, Karlsson Wang nicklas.karls...@karlssonwang.se wrote: I guess you have start calculation from the encoder counters each time and then there will be no problem with add up over time. There is a danger of encoder counters rolling over the signed-32 HAL pin value. (though the counter are internally promoted to 64 bits in all the LinuxCNC counters). Unfortunately the encoder_ratio is not applicable to Mesa / Pico / General Mechatronics / Pluto hardware counters. My hobber uses the floating point position values. There is a danger of loss of precision after many revolutions with this approach, but no risk of rollover-based problems. To be honest, I think the risk is a lot less now than it was back when that component was created. Back in the day, all HAL signals were limited to 32 bits. HAL floating point values were C floats which only have 24 bits of resolution. So you could see 1 degree of error after about 44,000 revolutions of the hob. I'm pretty sure that HAL floating point values are now C doubles, (thanks mostly to Jeff Epler if I recall correctly) which have 54 or 56 bit resolution. So this issue is far less likely to matter. It would now take 50 billion revolutions of the hob before the resolution caused a one degree error. -- John Kasunich jmkasun...@fastmail.fm -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On 30 July 2015 at 17:43, John Kasunich jmkasun...@fastmail.fm wrote: It would now take 50 billion revolutions of the hob before the resolution caused a one degree error. As my machine has a max spindle speed of 1000 rpm that leaves me pleasantly unconcerned. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Before i go bonkers: M98, M99
Brilliant! Mark On Wed, Jul 29, 2015 at 6:19 PM, Sebastian Kuzminsky s...@highlab.com wrote: I propose we make I Kill Kokomo the official code name of the next release. On 7/29/15 4:16 PM, Robert Ellenberg wrote: Sorry folks, it looks like I managed to butt-dial an email during my commute this morning. Crisis averted :) Rob -- One Man, One Machine, One Computer! VBSEG -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Before i go bonkers: M98, M99
On Wed, Jul 29, 2015 at 6:16 PM, Robert Ellenberg rwe...@gmail.com wrote: Sorry folks, it looks like I managed to butt-dial an email during my commute this morning. Crisis averted :) Rob Uh huh. Suurre. ;-) Mark -- One Man, One Machine, One Computer! VBSEG -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Before i go bonkers: M98, M99
On Thu, Jul 30, 2015 at 2:10 AM, George Ramsower georg...@gvtc.com wrote: This is interesting. I've seen this sort of thing on other email lists and thought it was some sort of spam or some type of malware. Now I understand it's just a mistake. I never thought of this possibility! Very interesting what we can do with our butts. George R. Thanks George. That image will be stuck in my mind for the rest of the day. TMI. ;-) Mark -- One Man, One Machine, One Computer! VBSEG -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 03:02:45 Marcus Bowman wrote: On 30 Jul 2015, at 03:51, Gene Heskett wrote: I bought a bag of small, roller tipped microswitches, and have a couple mounts laid out but not carved yet. Going thru searches on ebay just now, for both inductive, capacitative, and IR proximity switches, It sees like the majority of them are needing 6 volts or more, and around 300 ma each to function. Having seen some micropower capacitative switches in the textbooks of yore, it seems like the ball has been dropped in terms of being useful in a 5 volt logic circuit. Both the microswitch, and the inductive versions would seem to be sensitive to collecting swarf, particularly if its a rare earth magnet running a reed switch. My lathe seems to be relatively happy with a microswitch located under the back edge of the bed for Z homing where swarf tends to fall on past it, but x has to be kept swept clean because its actually on top of the carriage. I see a whole passel of stuff drilled onto GO704's in the hits I can get from google, but all of them preclude retaining the rubber swarf shields, which I'd say was not worth the tradeoff. There has to be a better way. So what sort of switches, and what swarf shielding to keep them relatively clean accurate are others using? PM's with pix appreciated if you have the time. Actually, this is a really interesting question. Having spent ages thinking about shielded locations for the mill, and about to do the same for the lathe, it would be useful if folks could put the pictures somewhere we could all see them. If anyone has any recommendations about makes and models of switches/sensors which provide better accuracy and repeatability than others, or useful ways of providing adjustment on mounting arrangements, that would also be very useful. Marcus My thoughts exactly Marcus. In my googling, something like 3/4ths of the sites that may have had helpful pictures, were behind a login requester. Since I am not a member of any of those Mach oriented groups, thats less than helpful. For X, I have considered removing the pointer which is also a mechanical limit stop, and likely demolishable to an out of control move as there are a couple OEM stoppers that would hit it. Once removed, then move one of the stopper knobs (they are in a 'T' slot in the front edge of the table) to someplace near the center of the table, and mount a switch that it would close on the way by which would function as the home switch. A similar setup is now on my lathe, with the switch under the back rail of what passes for a bed, located to be activated when no tool holder is mounted, and only 3/4 or so from the chuck face. X has already been homed and parked about 1mm from its outside limit. Having both switches well off center moderately well precludes its looking for the switch in the wrong direction as its z is normally parked well away from the work for gauge etc checking access to whats in the chuck. So this has worked well for a year for me. But I see no way to make certain that it looks in the right direction to find home on a mill without physically locating the switch well away from the center of the table. eg the switches trip point will need to be toward the end of the travel, and a HOME_OFFSET then used to put zero back at the center. From there, soft limits + - would be used in place of the existing knobs hitting the heavy centrally located pointer. There are not currently available, any such Y stops, so all of that will have to be imagined and built. Again, off center far enough that from any usual powerup location that it will search in the correct direction to find the switch, then a HOME-OFFSET that establishes a zero on the dro's at the center of travel, and again setting software limits from this arbitrary home rather than actual limit switches. Z homing will either be completely arbitrary because of uncalibrated tool lengths in an R8 spindle, or some sort of a pcb pad laying on the table and a G38.2 move to find the top, sensitive side of the pcb. In that case, how do I guarantee that I will remember to place the contact pad? It needs to be automatic, and that gets complex. I often do that on my toy mill, jogging down slowly till I get the probe tripped message, and then home it after rising even slower to open the contact so I can home it there, typically about .064 above the table. This would be more accurately done IF I could home with the probe tripped, but LCNC won't allow that. And I'm too lazy to put a switch in the probe lead. ;-) Or just sense someplace on the column call it home. That doesn't seem to be foolproof either, and I am absolutely the fool that will prove it. :) Thats why I ask for ideas pix. If you PM me pix, include perms to post them on my web page, and they will then be available for others till I fall over. Thanks. Cheers,
Re: [Emc-users] Switches for home, limits
Gene: I used (for better or worse) microswitches. X axis - you can see it to the left of one of the pics. Uses the original table stop and some of the screws that were in the table (for locking handles? can't remember off hand) http://cnc-for-model-engineers.blogspot.ca/2015/04/g0704-and-cnc-conversion-kit-last.html The Z and Y axis: http://cnc-for-model-engineers.blogspot.ca/2014/09/the-new-cnc-mill-kc20vsbf20g0704-part-3.html John. -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
A simple RC filter possibly combined with voltage division will remove noise although it will also reduce accuracy. I think low input impedance will fix the problem with noise because even though voltage may be high only a limited amount of current may be transferred by capacitive coupling or an electric field. Nicklas Karlsson Micropower On Thu, 30 Jul 2015 08:02:45 +0100 Marcus Bowman marcus.bow...@visible.eclipse.co.uk wrote: On 30 Jul 2015, at 03:51, Gene Heskett wrote: I bought a bag of small, roller tipped microswitches, and have a couple mounts laid out but not carved yet. Going thru searches on ebay just now, for both inductive, capacitative, and IR proximity switches, It sees like the majority of them are needing 6 volts or more, and around 300 ma each to function. Having seen some micropower capacitative switches in the textbooks of yore, it seems like the ball has been dropped in terms of being useful in a 5 volt logic circuit. Both the microswitch, and the inductive versions would seem to be sensitive to collecting swarf, particularly if its a rare earth magnet running a reed switch. My lathe seems to be relatively happy with a microswitch located under the back edge of the bed for Z homing where swarf tends to fall on past it, but x has to be kept swept clean because its actually on top of the carriage. I see a whole passel of stuff drilled onto GO704's in the hits I can get from google, but all of them preclude retaining the rubber swarf shields, which I'd say was not worth the tradeoff. There has to be a better way. So what sort of switches, and what swarf shielding to keep them relatively clean accurate are others using? PM's with pix appreciated if you have the time. Actually, this is a really interesting question. Having spent ages thinking about shielded locations for the mill, and about to do the same for the lathe, it would be useful if folks could put the pictures somewhere we could all see them. If anyone has any recommendations about makes and models of switches/sensors which provide better accuracy and repeatability than others, or useful ways of providing adjustment on mounting arrangements, that would also be very useful. Marcus Thanks. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
Sounds great. I bough a few hundred kilos of material probably intented for gears from bankcrupt company which i intend to use for testing machine. Nicklas Karlsson On Thu, 30 Jul 2015 10:09:51 +0100 andy pugh bodge...@gmail.com wrote: On 30 July 2015 at 07:16, Dave Caroline dave.thearchiv...@gmail.com wrote: Andy has implemented it on a mill http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Hobbing I have now created a dedicated hobbing GladeVCP panel which performs basic gear calculations (including span across teeth for size checking) as well as running the hobbing process. I will try to remember to add it to the Wiki page. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On 30 July 2015 at 08:02, Marcus Bowman marcus.bow...@visible.eclipse.co.uk wrote: it would be useful if folks could put the pictures somewhere we could all see them. I have been tending to embed inductive proxes in the machine somewhere with a drilled hole as the target. https://picasaweb.google.com/108164504656404380542/HarrisonMill#5989135693933177186 The Y-axis prox is embedded in the gib block, and uses a drilled hole target. The Z-axis is actually also on the gib block and the target is a metal block screwed to the main column casting. The X (not visible) is in a bolted-on block under the edge of the saddle with another drilled hole in the underdide of the table slide as the target. They can all get wet but X and Y are completely protected from swarf and the Z is out of the way of swarf. I bought 5 of the 8mm proximity sensors from eBay for less than £15. You want the ones where the outer threaded boy extends right to the end as the others won't work buried in metal. http://www.ebay.co.uk/itm/190836819378 For example. There may be arguments for buying more expensive ones for better reliability. Not immediately obvious is that they have an LED inside them to indicate status. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Gear hobbing machine
On 30 July 2015 at 07:16, Dave Caroline dave.thearchiv...@gmail.com wrote: Andy has implemented it on a mill http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Hobbing I have now created a dedicated hobbing GladeVCP panel which performs basic gear calculations (including span across teeth for size checking) as well as running the hobbing process. I will try to remember to add it to the Wiki page. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Switches for home, limits
On Thursday 30 July 2015 05:30:21 andy pugh wrote: On 30 July 2015 at 08:02, Marcus Bowman marcus.bow...@visible.eclipse.co.uk wrote: it would be useful if folks could put the pictures somewhere we could all see them. I have been tending to embed inductive proxes in the machine somewhere with a drilled hole as the target. https://picasaweb.google.com/108164504656404380542/HarrisonMill#598913 5693933177186 The Y-axis prox is embedded in the gib block, and uses a drilled hole target. The Z-axis is actually also on the gib block and the target is a metal block screwed to the main column casting. The X (not visible) is in a bolted-on block under the edge of the saddle with another drilled hole in the underdide of the table slide as the target. They can all get wet but X and Y are completely protected from swarf and the Z is out of the way of swarf. I bought 5 of the 8mm proximity sensors from eBay for less than £15. You want the ones where the outer threaded boy extends right to the end as the others won't work buried in metal. http://www.ebay.co.uk/itm/190836819378 These need at least 12 volts and 10 ma to function. I assume you use them as NC, opening when the hole is under the face? This would need some sort of a logic combiner unless quite a few pins are dedicated on the P2 plug of a 5i25. Not impossible Andy, just thinking out loud. :) The 2nd breakout is installed, but the BOB card I bought has the wrong gender connector, something I can't easily fix out here in the wilds of WV, USA. For example. There may be arguments for buying more expensive ones for better reliability. Not immediately obvious is that they have an LED inside them to indicate status. That would be as handy as sliced bread (for those that eat bread, us DM-II's steer as clear of it as we can) or bottled beer. 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-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Switches for home, limits
If you're going to use micro-switches, rather use this http://uk.rs-online.com/web/p/microswitches/1031645/?searchTerm=103-1645relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D6265724D504E266C753D656E266D6D3D6D61746368616C6C26706D3D5E5C647B337D5B5C732D2F255C2E2C5D5C647B332C347D2426706F3D313426736E3D592673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D3130332D3136343526 type; Notice how the button is almost directly under the roller, as opposed to the 'normal' type of being near the lever pivot. The indicated type will have increased switching sensitivity and lower hysteresis. Regards Roland On 30 July 2015 at 13:02, Gene Heskett ghesk...@wdtv.com wrote: On Thursday 30 July 2015 03:02:45 Marcus Bowman wrote: On 30 Jul 2015, at 03:51, Gene Heskett wrote: I bought a bag of small, roller tipped microswitches, and have a couple mounts laid out but not carved yet. Going thru searches on ebay just now, for both inductive, capacitative, and IR proximity switches, It sees like the majority of them are needing 6 volts or more, and around 300 ma each to function. Having seen some micropower capacitative switches in the textbooks of yore, it seems like the ball has been dropped in terms of being useful in a 5 volt logic circuit. Both the microswitch, and the inductive versions would seem to be sensitive to collecting swarf, particularly if its a rare earth magnet running a reed switch. My lathe seems to be relatively happy with a microswitch located under the back edge of the bed for Z homing where swarf tends to fall on past it, but x has to be kept swept clean because its actually on top of the carriage. I see a whole passel of stuff drilled onto GO704's in the hits I can get from google, but all of them preclude retaining the rubber swarf shields, which I'd say was not worth the tradeoff. There has to be a better way. So what sort of switches, and what swarf shielding to keep them relatively clean accurate are others using? PM's with pix appreciated if you have the time. Actually, this is a really interesting question. Having spent ages thinking about shielded locations for the mill, and about to do the same for the lathe, it would be useful if folks could put the pictures somewhere we could all see them. If anyone has any recommendations about makes and models of switches/sensors which provide better accuracy and repeatability than others, or useful ways of providing adjustment on mounting arrangements, that would also be very useful. Marcus My thoughts exactly Marcus. In my googling, something like 3/4ths of the sites that may have had helpful pictures, were behind a login requester. Since I am not a member of any of those Mach oriented groups, thats less than helpful. For X, I have considered removing the pointer which is also a mechanical limit stop, and likely demolishable to an out of control move as there are a couple OEM stoppers that would hit it. Once removed, then move one of the stopper knobs (they are in a 'T' slot in the front edge of the table) to someplace near the center of the table, and mount a switch that it would close on the way by which would function as the home switch. A similar setup is now on my lathe, with the switch under the back rail of what passes for a bed, located to be activated when no tool holder is mounted, and only 3/4 or so from the chuck face. X has already been homed and parked about 1mm from its outside limit. Having both switches well off center moderately well precludes its looking for the switch in the wrong direction as its z is normally parked well away from the work for gauge etc checking access to whats in the chuck. So this has worked well for a year for me. But I see no way to make certain that it looks in the right direction to find home on a mill without physically locating the switch well away from the center of the table. eg the switches trip point will need to be toward the end of the travel, and a HOME_OFFSET then used to put zero back at the center. From there, soft limits + - would be used in place of the existing knobs hitting the heavy centrally located pointer. There are not currently available, any such Y stops, so all of that will have to be imagined and built. Again, off center far enough that from any usual powerup location that it will search in the correct direction to find the switch, then a HOME-OFFSET that establishes a zero on the dro's at the center of travel, and again setting software limits from this arbitrary home rather than actual limit switches. Z homing will either be completely arbitrary because of uncalibrated tool lengths in an R8 spindle, or some sort of a pcb pad laying on the table and a G38.2 move to find the top, sensitive side of the pcb. In that case, how do I guarantee that I will remember to place the contact pad? It needs to be
