[FoxCNC1]

So I looked over the machine, everything is tight.
I used the MPG mode to jog 1" at at time and I was 0.985" in the X and something very similar on the Y. So I ran the Mach 3 Calibration again and I asked for 1" movements.
I dialed it to 1.002" +/- 0.001" Which is pretty good.

I noticed that mach 3 will not adjust the slave motor accordingly to its master, so I made the change manually.
Can you guys confirm this is correct ?

Everything seems to work well close to the origin.

I looked over my g-code in notepad, and I looks good, I even change it to stop and end at the location I tell it to go to.
I also ran two small simple programs (cut a 2"x2" square) and move to a specific location and it is all working well.

I am going to run a larger program in a minute just to make sure that it comes back to 0,0


I don't mind running a little slow if that mean accuracy. My motor settings after the mach 3 calibration os

X = 2043.526 / accel 29.79
y = 2064.314667 / aceel 29.49

[ger21]

What's the velocity?

[FoxCNC1]

X = 2043.526 / accel 29.79 / 595.8
y = 2064.314667 / aceel 29.49 / 589.8 (A is the same as Y)

These are the before values.

[FoxCNC1]

Just run a "crazy" program that jogged all over the place at 120 IPM.
At the end it returned to 0,0 so the machine is good.

I think I just need to change my workflow a bit for the top and just offset it from the edge, manually set 0,0 and cut each edge at a time.
Once I have all 4 done (2 per MDF sheet) I can bolt the bottom one down, run a program to drill holes for the clamp screws, then attach the spoil boards upside down, machine the recess for the nuts and drill, then remove, flip and install. Hopefully this time it will all line up.


PS:
Ger, What is the velocity and should it be set the same on all motors?
I am also gathering that the acceleration value is how many seconds it will take to get to the Velocity?

[ger21]

The velocity setting is right next to the acceleration setting. It may be able to be the same for all motors, but each axis should be tested independently to determine a reliable maximum.

120ipm is slow. If you are losing position, it would usually happen during rapid moves, which is what the velocity setting is.

[FoxCNC1]

I need to look at the after settings.

[ger21]

Mach3 doesn't adjust accel and velocity for you. You must do it yourself, through trial and error as I said. I would guess, though, that the 30 and 600 numbers are conservative settings based on testing from CNC ROuter Parts, so you may not need to test them. I'd ask them for their opinion.

Stpes per unit can be calculated, but ultimately depend on the accuracy and consistency of the rack and pinion or screws, which can vary. In some cases the calculate values will be correct. In other cases, they can be much different.

But as I said, jogging at 120ipm doesn't tell you if the machine will lose position, as it moves at 600ipm during rapid moves. I'd make a complex program using all rapid moves. Take the program you had before, and do a find and replace and replace all G1 moves with G0 moves.

[FoxCNC1]

Mach3 doesn't adjust accel and velocity for you. You must do it yourself,

What is weird. I will check again, but I don't ever recall changing those values manually.
You are right, the dialog box say, we will adjust step to xxxx.xxxxx. But it also changes acceleration and velocity.

[FoxCNC1]

I came home today and ran the calibration again after a short phone call with CNCRP. (Ahren)

He mentioned that I should try to calibrate my machine over a longer distance rather than 1" at a time. So i did this and the steps got very close to the values they had initially provided. He assured me that while they have tested their builds, I should really take their XML as a baseline (which is what I thought).

Now going to back to what is changed by mach 3: Mach 3 will change the steps and will slightly change the acceleration and speed. Ahren explained to me that such a minute change does not affect anything and is essentially the result of Mach 3 liking to work with numbers that are multiples of 2. Anyway, the machine jog 12",24" and 1" "consistently"


I just double checked again and it working good. (moving correctly)

I still think that I am going to cut way from the edge of the table and just do one edge at a time like suggested.