mach3

[blackburn mark]

it sounds like your max speed is lower than any of the speed called from your g-code... eg, if your max speed is 800mm/min and your g-code calls for 3000mm/min mach will rapid your machine at 800mm/min
whats the top speed you have set in motor tuning in mach?

[edgas10]

i had a 14mm screw with 2 mm pitch , but this was before i dissassemble my machine.
now i´ve upgraded her with belts (15tooth around 12mm diameter) witch give me much more speed.
but i have not assembled the machine yet ,so i cannot tell you the speed setting now. maybe this weekend.
whem a have this assembled i´ll put my speed settings here so you can help me!!
thanks for the fast answer
edgar

[blackburn mark]

ok im with you... you will need to exsperiment with your motor tunings to see what the machine will run at with the new fittings.
keep upping the top speed until your steppers start stalling then back off the speed by maybe 20%
you will also need to do some mathermatics to work out how may steps per unit and update that in motor tuning (you can do this automaticaly if you have a dti but its probably better to get the calculator out and do the maths:)
let us know if you get stuck :)