On 6 November 2014 23:06, Marshland Engineering <[email protected]> wrote:
> The motors are approx 400w Continuous and 60oz/inches. My brain is bit rusty > and there are so many incorrect formula on the web, I can't seem to get the > calcs correct to see if these are powerful enough. All my cals show very low > power levels. Well, it basically takes no power at all to move your machine at constant speed. What you need to consider is how much energy is in the moving parts at full speed and how long it takes to get there, and then you have an estimate of power required. So, 50kg or table + work (and spinny bits. which might be worth calculating properly). 10 m/min gives a surprisingly low 0.7 joules. Plan on getting up to full rapid speed in 10mm, which I think takes 0.12 seconds (twice as long as it takes to do 10mm at 10m/min once at speed) So, that's only 5W of mechanical energy to accelerate. (which I think just means that you are not power-limited). That is also an acceleration of 1.4m/s2 which needs a force of 70N, or a torque on 5mm pitch screws of 0.4Nm. 400W sounds like plenty, and given that 50W steppers on my lathe do OK, perhaps these numbers are not too far off. Slide friction will eat a lot of power (power = force x velocity) but I don't have much feel for what the sliding friction is. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
