Hi Bobby:
I can see a problem or two in your tests..
All your boxes show on takeoff the laser isn't shooting at the start..
This may explain small circles as they never get up to speed. So a couple things to discuss..
.
First, as the laser takes off on a move, the formula for power internall
y is
max( minpwmset
ting , (ActualSpe
ed / Feedrate) * power )
So in the config, the minPWM sets the startup cutting power as the axis
starts to move if the axis is so slow the power computed is less than minPWM.
SO to set this approxima
tely correct, make a square
in gcode. Cut it as you have and if there is no burn at the start of each
corner increase the setting Planner/MinPWM until you see each corner
has been cut. Set you feedrate so your table actually hits it in the velocity DRO,
(or close anyway, it doesnt have to be perfect..
but if you see 1589 is the fastest
it goes, set the feedrate to 1600 or so. )
The second problem is that feedrate and jerk are related. Jerk is defined
as the amount of mechanica
l jerk the machine can do, or how much jerk
occurs during a move. As its lowered, the axis will move slower. As its raised,
the axis will move faster.If this is too low, you will not be able to move
fast enough on small segment programs. Another considera
tion is
look ahead. If a circle is made of hundreds of Gcode lines, the program
can only see ahead by the setting of Lookahead
. Change this to
300 or so and it can see and thus plan for higher speeds.
If you run a program without laser on, see what max feedrate is achived in
that small circle , the math is that a small circle may never hit the feedrate
you desire, so power will never hit it as well. For example, if your feedrate
is set to 5000, and you have 2 circles, one large and one very small.
The feedrate in the large may hit 4000 ( for example) but the small
circle may only hie 1000. If so , the power of the small circle will be 1/4th
the power of the large. In this case the feedrate for the program should
be set to 1000. (Or a feedrate for the small circle of 1000 and for the large
4000.)
Jerk in a circle is computed as a function of its radius. The larger the
radius and mathemati
cally the smaller the resultant jerk. Smaller circles
have larger jerk.
So I would first look to the square and adjust the minPWM to make it
start that corner with power high enough to burn. If you turn off
DistCorre
ction ( button on the laser control), you will then get
the set laser power at all times during motion, which can be fine in cutting
but will cut harder when its slow due to planning motion.
It takes some playing to get this right. Unlike normal CNC where motion
alone is enough to cut, Auggie needs to get the power to be properly proportio
nal
to speed, which is why all the power settings.
Let me know how the squares corners come out with adjustmen
ts and we'll go
from there.

Thx
Art