Re: [Emc-users] Encoders with no Index
Igor Chudov wrote: Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? The problem is how do you synchronize two taps, in different holders, so that the threads are synched? I really don't think rigid tapping with a roughing and a finish tap is practical. Probably the only way to do it would be to rigid tap with the plug tap, change to the finish tap but leave the holder loose and manually start it into the hole, and let the existing threads synch the tap. Then, tighten the tap holder while it is still in the hole. This is not what I'd call a reasonable shop operation. Jon -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
Igor Chudov wrote: Stuart, what I mean is this: 1) Drill a hole for tapping 2) Tap with a plug tap Is that possible with a CNC mill equipped for rigid tapping? (like mine)? It depends on the hole size, the thread engagement, the material, the thickness of the material, etc. I am sure you could do this in thin aluminum with an adequate hole diameter. I am sure you will have an accident attempting to do the same in thick stainless. I have a lot of experience now rigid tapping in various aluminum parts, but all with smaller taps from 2-56 up to 10-32. it was really COOL to watch it tap fairly deep holes with a 2-56 tap! All I had to do was brush the chips out of the tap's flutes every hole with a toothbrush soaked with alum-tap, and it went beautifully. But, proper tap selection really makes all the difference. Try to do too deep a hole with spiral flute taps and they choke on their own chip and break. So, I have a selection of combined drill-taps (thin material only, no more than 2X major diameter), spiral flute (maybe 3-4 X diameter) and spiral point for anything deeper. Jon -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On 17 February 2011 19:19, Jon Elson el...@pico-systems.com wrote: Probably the only way to do it would be to rigid tap with the plug tap, change to the finish tap but leave the holder loose and manually start it into the hole, and let the existing threads synch the tap. Then, tighten the tap holder while it is still in the hole. This is not what I'd call a reasonable shop operation. Once set up though, with indexed holders (such as BT, CAT, INT) it should carry on working. However, this all seems a bit of a diversion from the original question... -- atp Torque wrenches are for the obedience of fools and the guidance of wise men -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
Rigid tapping will always need two pins to sense direction, but unless people do multi-pass tapping (and I guess they might, with taper, second and plug (yikes!)) the index serves only to start the cycle so should be perfectly safe to derive synthetically. Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, 16 Feb 2011, andy pugh wrote: Date: Wed, 16 Feb 2011 19:21:01 +0200 From: andy pugh bodge...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: [Emc-users] Encoders with no Index Is there any reason why it would be a bad idea to derive an index pulse in software? I am thinking about situations where folk are short of P-port pins but want to tap/thread etc. You can do lathe threading with one pulse per rev and a single pin, but I can't help feeling that multiple pulses and a software-derived index would work better (whether is is done with modulo division cobbled together with HAL functions, a custom component, or even a mod to the existing encoder counter) Rigid tapping will always need two pins to sense direction, but unless people do multi-pass tapping (and I guess they might, with taper, second and plug (yikes!)) the index serves only to start the cycle so should be perfectly safe to derive synthetically. -- atp Torque wrenches are for the obedience of fools and the guidance of wise men Seems reasonable to me, no help for spindle orient but fine for rigid tapping/threading. Your synthesized index reference position should persist until EMC is shut down, so really no different than a true index except: 1. Random relation to spindle orientation 2. Orientiation changes every EMC startup I guess the mod function could allow for encoders with non 1-1 gear/belt ratios with the spindle Peter Wallace Mesa Electronics -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
Someone reading on a parport near/above to max speed could miss a pulse and not know. Shouldnt be doing that but Even with a pulse over speed just gives you a drunk thread no error condition. I cant think how one would set the offsets for a set of plug/middle/taper taps as they wont be consistently on the same helix, a measuring nightmare, use machine taps as they are designed for a single tap to do the work and have the correct swarf clearance flutes for cnc work. Dave Caroline On Wed, Feb 16, 2011 at 5:21 PM, andy pugh bodge...@gmail.com wrote: Is there any reason why it would be a bad idea to derive an index pulse in software? I am thinking about situations where folk are short of P-port pins but want to tap/thread etc. You can do lathe threading with one pulse per rev and a single pin, but I can't help feeling that multiple pulses and a software-derived index would work better (whether is is done with modulo division cobbled together with HAL functions, a custom component, or even a mod to the existing encoder counter) Rigid tapping will always need two pins to sense direction, but unless people do multi-pass tapping (and I guess they might, with taper, second and plug (yikes!)) the index serves only to start the cycle so should be perfectly safe to derive synthetically. -- atp Torque wrenches are for the obedience of fools and the guidance of wise men -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, Feb 16, 2011 at 11:28 AM, Igor Chudov ichu...@gmail.com wrote: Rigid tapping will always need two pins to sense direction, but unless people do multi-pass tapping (and I guess they might, with taper, second and plug (yikes!)) the index serves only to start the cycle so should be perfectly safe to derive synthetically. Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? that would be tricky - maybe an optical comparator to make sure the helix is in the proper orientation. interesting Stuart dos centavos -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, Feb 16, 2011 at 2:04 PM, Stuart Stevenson stus...@gmail.com wrote: On Wed, Feb 16, 2011 at 11:28 AM, Igor Chudov ichu...@gmail.com wrote: Rigid tapping will always need two pins to sense direction, but unless people do multi-pass tapping (and I guess they might, with taper, second and plug (yikes!)) the index serves only to start the cycle so should be perfectly safe to derive synthetically. Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? that would be tricky - maybe an optical comparator to make sure the helix is in the proper orientation. interesting Stuart Stuart, what I mean is this: 1) Drill a hole for tapping 2) Tap with a plug tap Is that possible with a CNC mill equipped for rigid tapping? (like mine)? -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, Feb 16, 2011 at 02:04:45PM -0600, Stuart Stevenson wrote: that would be tricky - maybe an optical comparator to make sure the helix is in the proper orientation. interesting Stuart Yes - it would work fine - all you have to do is get the two taps in the holders oriented the same way. Seems like you could do it optically or with some clever fixture. If you have something matching your spindle taper that can sit upright on a surface plate, a height gauge, and a piece of material with a good matching thread in it, it seems like you could get the taps aligned pretty easily. Collets would be harder than set screw holders, because they'd pull in when you tighten them. -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, Feb 16, 2011 at 2:12 PM, Chris Radek ch...@timeguy.com wrote: On Wed, Feb 16, 2011 at 02:04:45PM -0600, Stuart Stevenson wrote: that would be tricky - maybe an optical comparator to make sure the helix is in the proper orientation. interesting Stuart Yes - it would work fine - all you have to do is get the two taps in the holders oriented the same way. Seems like you could do it optically or with some clever fixture. Guys, my question was not about re-entering tapped holes. It is about tapping a hole with a plug tap as one, first and only tapping operation, in a CNC mill equipped for tapping. Would that work, mechanically? If you have something matching your spindle taper that can sit upright on a surface plate, a height gauge, and a piece of material with a good matching thread in it, it seems like you could get the taps aligned pretty easily. Collets would be harder than set screw holders, because they'd pull in when you tighten them. -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, Feb 16, 2011 at 02:21:40PM -0600, Igor Chudov wrote: Guys, my question was not about re-entering tapped holes. It is about tapping a hole with a plug tap as one, first and only tapping operation, in a CNC mill equipped for tapping. Would that work, mechanically? Wow did we misunderstand. I don't think it would be very successful to use a bottoming/plug tap as the first and only tap (whether on a mill or by hand) - if you try it, let us know! -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
Wow did we misunderstand. yes definitely I don't think it would be very successful to use a bottoming/plug tap as the first and only tap (whether on a mill or by hand) - if you try it, let us know! depends on the material and tap depth and percentage of thread (tap drill diameter) etc considered answer - yes but not often Stuart -- dos centavos -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On 16 February 2011 19:28, Igor Chudov ichu...@gmail.com wrote: Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? Probably, but one flute of one thread cuts the whole thread. With a taper tap the work is shared over several teeth and flutes. Machine taps are somewhere in the middle, not needing the self-aligning taper of a hand tap, but not threading right to the bottom like a plug tap either. -- atp Torque wrenches are for the obedience of fools and the guidance of wise men -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders with no Index
On Wed, 16 Feb 2011 23:05:21 +0200, you wrote: On 16 February 2011 19:28, Igor Chudov ichu...@gmail.com wrote: Which brings up a question, can one tap with a plug tap first, on a CNC mill that is equipped for rigid tapping? Probably, but one flute of one thread cuts the whole thread. With a taper tap the work is shared over several teeth and flutes. Machine taps are somewhere in the middle, not needing the self-aligning taper of a hand tap, but not threading right to the bottom like a plug tap either. There are predominantly two types of machine taps. For through holes there are spiral point taps, very much like a conventional hand second tap. For blind holes use spiral flute taps. They don't thread all the way to the bottom, but not far off - certainly better than some of the hand plug taps I have with pointed ends! Here's a link with a picture of both types on one page http://www.cutweltools.co.uk/files/ww/BSP%20Spiral%20Flute%20%20Spiral%20Point.pdf As for using hand plug taps for machine tapping - I wouldn't, they have a nasty habit of snapping off in the hole! My spark eroder has earned some good money because of that - it cost's far more than the price of a machine tap to remove a broken one from a blind hole ;) Steve Blackmore -- -- The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
