Couple cut quality concerns..Circles and dirrection changes

[tm america]

I am running a 4x8 5 axis machine i built using tb6560 controller running mach3.I have a water table and am running a hypertherm pm45.First issue i have is circles not coming out perfectly round..I have tried running different accell rates and feed rates but seems to only change where the over cut is at.Second issue i am having is on dirrection changes like the corners of a square i get a ripple in the cut .. yet again tried different feed rates and accell rates . It seems what makes the circles better makes the corners worse..To me it looks like in corners it is fanning the arc out till it gets up to full cut speed. and in circles i am getting an undercut till the torch gets to full cut speed.I am running arcs for my lead ins and lead outs I am running the pm45 at 45 amps with the 45 amp consumables with a machine torch.Pressure is at around 120psi. i was getting alot of dross when i ran it at the recommended pressure.I have an automatic water drain on the compresssor. 4 water separators and two filters plus the one on the machine..All my filters and water separators are 1/2 inch and i am running 1/2 inch line tile right at the cutter.Any suggestions would be greatly helpful

[rikduk]

First of all. i would check everything moving on the table to see if it is loose.
Grab the torch body and try to shake it.
The ripple right after a square corner is either something loose, or your gantry flexing.
If everything is thight, you have to slow down cutting speeds.

I'm not sure about your circle, pics?

You say 5 axis table...im curious, the way i count:
1: X
2: Y
3: Z
4: rotary
5: ?
Or maybe we'renot counting the same way?

[acourtjester]

Are you using Sheetcam and using path rules that change the cutting speeds for corners of for the sizse of circles. I tried to use those and got the wiggle cut in the corner due to the change in speed to get sharp corners. I since have removed them.
Also in Mach 3 there is a CV control for movement in plans mode in the corners see attached from manual. It is located in the config, general config on the right side of the screen.

[tm america]

I'm thinking it is something to do with the cv control tolerances.. On the computer i have running the machine there is no setting for the cv just plasma mode and nothing else. but on the version i have on my other computers it has the settings for it..I'm gonna delete and reinstall mach3 and see what it does when using cv mode without plasma mode.. .Right now it seems like if you don't use plasma mode it is running in exact stop mode..I didn't have any of these issues before my plasma cutter crapped out and i switched to the hypertherm pm45.. so i'm thinking the other plasma cutter backfed the computer and is making mach3 act crazy.. I went over everything on the machine . i installed new belts did a full calibration and even measured and set for backlash which was very minimal .My machine has no play in any of the axis..and when i say 5 axis i have x axis. y axis. z axis is the plasma torch . c axis is the rotary. b axis is by router.I have pretty good resolution on my machine my steps per inch are 500 for the x axis 600 for the y axis and 3200 for z and b axis and i vary the c with the diameter of tube but it is something like 6400 for 6 inch diameter round.when i watch it cutting the machine itself is not jittery i think the plasma arc is fanning out more because the slow down on direction change... and as far as the circles it looks like the same thing about half way around where it gets up to full speed things smooth out and are perfectly round.It is like the first inch of cutting after a hard direction change or start of a cut

[tm america]

Also it does it in any direction even if it goes from a straight to an angle..i would think if it was a axis having play it would be more in x or y but not the same either way and it wouldn't follow a curve on the start of a circle..??

[acourtjester]

I do not have the plasma box checked in CV mode
CV dist tolerance is checked and set to 25 units and
G100 adaptive Nurbs CV is checked
stop CV on angle is not checked and no degrees set in the box
This must be the way Mach set it up as I have not ckecked anything in CV mode.

[tm america]

I do not have the plasma box checked in CV mode
CV dist tolerance is checked and set to 25 units and
G100 adaptive Nurbs CV is checked
stop CV on angle is not checked and no degrees set in the box
This must be the way Mach set it up as I have not ckecked anything in CV mode.

Thanks i will try those settings.. and hopefully it gets me taken care of..