Ray, That's the biggest proplem. How many people have access to the tools to accuratley measure the machine errors when your talking 30 or 60 inches of travel? I left all those big machines, 6' x 8' surface plates and CMMs to move to the country. A well equiped complete machine shop is the only part I really miss. But the proper way to fix a machine that is out of square is to make it square :)
It will be accurate enough to make guitars and cabinetry at the very least. As far as metal working well we'll see? I'll make a plea for the laser set-up when it's needed for final tweaking. Cheers, Dale Ray Henry wrote: > A non-trivial kinematics can be used to square up a machine or > compensate for rotaries being a bit out of perpendicular with each > other. If I remember right we did a bit of this for a home built mill > for a student who was able to borrow a Renishaw Ball Bar for testing. > > Rayh > > > On Sat, 2007-10-06 at 13:27 -0400, Dale wrote: > >>I see this idea come up every now and then. If the Machine is not square >> then you square up the machine. If the ways are worn then you refinish >>them, and If the lead screws ar worn you replace them. You're right it >>is impossible to build a perfect tilting rotary table, or anything else >>no matter how small the error may be. I have used tilting rotary tables >>to inspect parts and you'd need to look damn hard to find the >>inaccuracies in those tables. I know from working with machinery fo 34 >>years that unless you have some instrument that can measure in micro >>inches you can't acheive micro inch precision. In order to compensate >>more all the machine and tooling inaccuracies you first have to be able >>to measure them. In manufacturing every dimension has a tolerance >>appropriate for each and every feature of the part to be machined. Not >>everything needs to be perfect. It's not difficult to align tooling of >>any kind on a machine including a tilting rotary table. Besides the >>ability to measure accurately there are thermal factors. Rigidity of the >>machine and tool holders is not constant. The longer you have to reach >>the more deflection you will encounter. The amount of deflection also >>changes as the cutting tool wears as well as with feeds and speeds. You >>are talking about a huge battle to get software to compensate for what >>is part of a machinsts job. If the machine is not up to the task I would >>consider it a loosing battle. Before taking on such a challenge I'd >>strongly suggest that the machine and tooling is up to specs in order to >> even have a chance at a successfull implemantation. Like it's been >>said, "You can't make a silk purse out of a sow's ear". >> >>I wish you the best of luck and do hope you keep us all informed as to >>your progress and successes/failures. To have EMC compensate for >>inaccuracies in the machine alignment would be a great asset. If I >>should ever find the room to contine building my second (larger) >>machine. It sure would be nice, there are limits as to just how accurate >>I can build and align a machine in my garage. >> >>Dale >> >> >>Stuart Stevenson wrote: >> >>>Gentlemen, >>> I want to start a dialog concerning how best to implement geometry >>>compensation. At this point I am not thinking about roll, pitch and >>>yaw. These may be included but my main concern is the manufacturing >>>inaccuracies of multiple rotary motion components. >>> It is impossible to build a perfect tilting rotary table. The >>>intersection of the axes will not be perfect. >>>I would like to have registers to hold compensation values >>>representing the determined manufacturing inaccuracies. This would >>>allow the control to compensate the linear motion positions to >>>'perfect' the tilting rotary table. >>> I have just requested three items. This is the fourth. If I am >>>successful in the implementation the the three items I should be much >>>more able to address this myself. >>> >>>Any and all suggestions and comments are welcome. >>> >>>thanks >>>Stuart >>> >>>------------------------------------------------------------------------- >>>This SF.net email is sponsored by: Splunk Inc. >>>Still grepping through log files to find problems? Stop. >>>Now Search log events and configuration files using AJAX and a browser. >>>Download your FREE copy of Splunk now >> http://get.splunk.com/ >>>_______________________________________________ >>>Emc-users mailing list >>>[email protected] >>>https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> >> >>------------------------------------------------------------------------- >>This SF.net email is sponsored by: Splunk Inc. >>Still grepping through log files to find problems? Stop. >>Now Search log events and configuration files using AJAX and a browser. >>Download your FREE copy of Splunk now >> http://get.splunk.com/ >>_______________________________________________ >>Emc-users mailing list >>[email protected] >>https://lists.sourceforge.net/lists/listinfo/emc-users >> > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
