On 9 November 2013 10:58, aaron moore <aaronmo...@linuxmail.org> wrote:
> The main one is low feed speed. I have tried editing the code and increasing > feed and acceleration in the ini file to increase the speed, but in makes no > difference. I am trying to cut a helical final cut, which seems to have lots > of tiny moves, but other files I have tried are almost as slow. Can any one > offer some advice? The "lots of tiny moves" might be the problem. What is the acceleration on the rotary axis? Is it anywhere near the actual physical maximum? You simply might not have increased the A-axis accel enough. The scaling on rotary axes is such that you can end up with some very big numbers indeed. Consider a direct-coupled 5mm pitch ballscrew, and a direct-coupled rotary axis both coupled to a motor that can accelerate at 25,000 steps/sec/sec. That gives you a linear acceleration of 625mm/s/s or 25 inch/s/s or 45,000 degrees/s/s. Even geared 30:1 with a worm gear your rotary axis acceleration is likely to be twice the linear accel in mm or 60 x in inches. (and that was assuming no gearing between the motors and screws). The reason this matters is that LinuxCNC likes to be able to stop by the end of the next move (this is because it doesn't plan beyond the end of the next move, which is something being actively worked on at the moment). How fast will a simple G1 X500 A7200 run? If that runs good and fast, then that is a sign that it is lookahead related, and lookahead issues are made much worse by low acceleration values. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ November Webinars for C, C++, Fortran Developers Accelerate application performance with scalable programming models. Explore techniques for threading, error checking, porting, and tuning. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
