Re: [Emc-users] Knee mill w/ encoder on knee
Sven, How did you fit the knee motor? I'm considering it myself but looking for some more details. I figure I'd have to mount knee limits on both ends of travel, and figure out how to fix the motor. Matt I didn't, both the Abene and the Deckel was factory built. The guys I know that have made a knee-Z on Bridgeports have done it in different ways. The simple solution is a motor on the shaft for the crank. The De Luxe version is a new ballscrew and a rotating nut. Both runs, one is super exact but expensive... /S -- Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_sfd2d_oct ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
2012/9/14 Stephen Dubovsky smdubov...@gmail.com Dave, The knee typically isn't under CNC control on a knee mill. You move it up/down manually, lock it, re-touch off, and continue a program. Just wondering if its possible to keep track of the Z location w/o causing LCNC from running into the soft limits. ... In my previous work I've been using two different CNC machines - factory built - with the Z operating the knee. One Deckel Maho and one Abene. I know at least four CNCified Bridgeport clones with knee operation. I also now one machine that operates both the knee and the quill simultaneously. Runs like a charm. :) /S -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
I always wanted one of the bridgeport series II knee ballscrews. Don't know if it will fit on my machine, and seems potentially deadly, but it would be nice. Would also be nice if the counterbalance piston would magically start working. On Tue, Oct 16, 2012 at 3:07 PM, Sven Wesley svenne.d...@gmail.com wrote: 2012/9/14 Stephen Dubovsky smdubov...@gmail.com Dave, The knee typically isn't under CNC control on a knee mill. You move it up/down manually, lock it, re-touch off, and continue a program. Just wondering if its possible to keep track of the Z location w/o causing LCNC from running into the soft limits. ... In my previous work I've been using two different CNC machines - factory built - with the Z operating the knee. One Deckel Maho and one Abene. I know at least four CNCified Bridgeport clones with knee operation. I also now one machine that operates both the knee and the quill simultaneously. Runs like a charm. :) /S -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
On 10/16/2012 03:24 PM, Eric Keller wrote: Would also be nice if the counterbalance piston would magically start working. My buddy Joe the maintenance guy magically disassembled the counterbalancers on the big gantry CNC machine I'm retrofitting to LinuxCNC, then he magically rebuilt it, and then it magically started working again! :-) -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
apparently there is a leather seal on the piston that doesn't work. I think it's going to take the same kind of magic that Joe used to get it to seal again. Pain. On Tue, Oct 16, 2012 at 3:32 PM, Bruce Layne linux...@thinkingdevices.comwrote: On 10/16/2012 03:24 PM, Eric Keller wrote: Would also be nice if the counterbalance piston would magically start working. My buddy Joe the maintenance guy magically disassembled the counterbalancers on the big gantry CNC machine I'm retrofitting to LinuxCNC, then he magically rebuilt it, and then it magically started working again! :-) -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
Sven, How did you fit the knee motor? I'm considering it myself but looking for some more details. I figure I'd have to mount knee limits on both ends of travel, and figure out how to fix the motor. Matt -- Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_sfd2d_oct ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
On 09/14/2012 12:47 PM, Stephen Dubovsky wrote: This all comes from thinking about manual machines w/ DROs. There are combiner boxes avail that take a scale on both the quill and knee and add/subtract them to feed into the DRO display. Some newer ones can do it internally I think. So it doesn't matter which you move, the Z axis display on the DRO reads the total. Move the quill up 2 and the knee up 2 and the Z display stays the same. You don't need to touch-off again, and again, and again, ... Stephen, I'm interested in what you come up with. The mill I work on has a knee with a ballscrew, connected to a crank and a motor drive, so I think an encoder on the screw would do nicely. As it is I sometimes put pauses in the Gcode with a message to the operator to move the knee up or down by a certain amount. After the pause it does the tool change, followed by a change to a different coordinate system to handle the new knee position. It's a bit crude but works. Karl -- Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://ad.doubleclick.net/clk;258768047;13503038;j? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
My Bridgeport Interact has an encoder on the motor that turns the knee screw, it is nice. -- Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://ad.doubleclick.net/clk;258768047;13503038;j? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Knee mill w/ encoder on knee
I was wondering...(can you smell the smoke?) On manual knee mills there are often ways to combine the knee and quill scales in the DRO to directly add/subtract from one another, giving only one combined Z reading. This part would be easy enough to do in HAL on a CNC. Add/subtract the quill encoder to the knee's linear encoder(scale). If the drives were enabled (but not necessarily cutting), the quill would even 'chase' the knees position trying to hold a commanded Z. But how would you change the soft limits? You basically need to be able to add the knee's position delta to each the Z+ and Z- limits. Are those accessible in HAL? On a manual bridgeport moving the knee up and down for different tools w/ greatly varying lengths (endmill vs tapping head) is de rigeur. Just wondering if the same can be accomplished on a CNC during tool changes to stay within the quills range of travel and preventing re-touching off each time. Stephen -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
On Fri, Sep 14, 2012 at 2:44 PM, Stephen Dubovsky smdubov...@gmail.com wrote: I was wondering...(can you smell the smoke?) On manual knee mills there are often ways to combine the knee and quill scales in the DRO to directly add/subtract from one another, giving only one combined Z reading. This part would be easy enough to do in HAL on a CNC. Add/subtract the quill encoder to the knee's linear encoder(scale). If the drives were enabled (but not necessarily cutting), the quill would even 'chase' the knees position trying to hold a commanded Z. But how would you change the soft limits? You basically need to be able to add the knee's position delta to each the Z+ and Z- limits. Are those accessible in HAL? On a manual bridgeport moving the knee up and down for different tools w/ greatly varying lengths (endmill vs tapping head) is de rigeur. Just wondering if the same can be accomplished on a CNC during tool changes to stay within the quills range of travel and preventing re-touching off each time. Perhaps one just moves a percentage of all Z moves eg+75% to one and -25% to the other (ratio depends on maximum travels of the machine) to both knee and quill at the same time to get maximum travel. I realise that does not optimise the speed of the quill when tapping but may be an easy hal fiddle Dave Caroline -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
On 14 Sep 2012, at 15:44, Stephen Dubovsky smdubov...@gmail.com wrote: But how would you change the soft limits? The limits are joint not axis limits, so I think it is a non-issue. -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
Dave, The knee typically isn't under CNC control on a knee mill. You move it up/down manually, lock it, re-touch off, and continue a program. Just wondering if its possible to keep track of the Z location w/o causing LCNC from running into the soft limits. Andy, Ok, joint level: that makes some more sense. I'll have to look into that more. That would involve adding the encoders/scales togethers in the kinematics? Im never touched that so am ignorant of that stuff so far. -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
On Fri, Sep 14, 2012 at 9:44 AM, Stephen Dubovsky smdubov...@gmail.com wrote: On manual knee mills there are often ways to combine the knee and quill scales in the DRO to directly add/subtract from one another, giving only one combined Z reading. This part would be easy enough to do in HAL on a CNC. Add/subtract the quill encoder to the knee's linear encoder(scale). If the drives were enabled (but not necessarily cutting), the quill would even 'chase' the knees position trying to hold a commanded Z. I can see some issues to think about: - a given Z is not unique: what method do you use? hold the knee, move the quill? hold quill, move knee? coordinated move of both at an arbitrary ratio? what if you hit limit on one? - there's probably a different accuracy and backlash on the quill vs. the knee. It might be a challenge to linearise the setup for reliable positioning, even if one used a fixed strategy. - if you had a good, reliable actuators on both, it might actually result in increased precision, by using differential drive -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Knee mill w/ encoder on knee
Przemek, As I said to Dave, there is almost never a power drive on the knee. So, figuring out which to move via CNC is a trivial exercise;) But you have to move the knee between operations for different length tools all the time. And the quill of a BP isn't the stiffest thing around so you typically want it as retracted as possible (yet still be able to reach the clearance plane.) This all comes from thinking about manual machines w/ DROs. There are combiner boxes avail that take a scale on both the quill and knee and add/subtract them to feed into the DRO display. Some newer ones can do it internally I think. So it doesn't matter which you move, the Z axis display on the DRO reads the total. Move the quill up 2 and the knee up 2 and the Z display stays the same. You don't need to touch-off again, and again, and again, ... Imagine doing some 3D profiling w/ a short endmill. You'd want the knee fairly high to maximize quill stiffness. When you get to a M6 tool change, say to a long drill or tapping head, you could load the tool and lower the knee until there was safe clearance and press cycle start again. Next M6 you can do the same. It would be slickest to write some sort of macro Accuracy backlash on a knee screw isn't a problem if you have a glass scale (or equivalent) mounted;) As long as you remember to lock it every time before cutting like you're supposed to, its all good. -- Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
