seting origin

[charlieuk]

for some reason I always struggle with trying to get the arrows to go in the correct direction to what I want! my machine has the zero at the far right hand corner in this picture so I want to set the x down the long edge of the part the y coming across the part and z going up from the bottom right hand corner of the stock box but for the life of me cant get my head around how to and cant figure the lodgic but know it should be simple!

[LibertyMachine]

In your attached image, you have the orientation correct, it's just at the wrong side of the part, is that right?

[charlieuk]

the x and z are correct but I want y going the opposite direction ideally I think 

well that's the way my brain is telling me I should do it.. happy to be told other wise

[LibertyMachine]

That is a configuration that is impossible, like asking for a square circle. The arrows indicate positive direction of travel. Here's an example:

Extend your left hand and make a fist. Pop your thumb up and point it at the ceiling. This is the Z axis.

Point your index finger at the screen in front of you, this is the Y axis

Point your middle finger and have it run parallel to your desk/keyboard etc. This is the X axis.

Each one of these would be positive directions of travel as far as the Cartesian Coordinate System is concerned, and that is what the whole basis of CNC machines are designed around. This is the meaning of the arrows in Fusion.

Does that help any?

The best we could do is get it over to the other side, which is simply a matter of picking that point

[charlieuk]

cheers many thanks I think then when I built my machine because of its design being a cantilever I got it a bit backwards, I only have used it up until now on a with a surfboard program that doesn't seam to mind what direction things are.

it could be a bit of a headache to change it all around as I'm going to have to move the home position and figure how to change it in mach3 which I have forgotten how I set up.

I'm just designing another machine which I will try and get it right on!

the pic bellow shows the axis although z+ is down not up.

[LibertyMachine]

Since you are using Mach3, it's a simple matter to change it's configuration, inside the software (I believe this is where you need to go)

How you built the machine doesn't have any impact on what's positive or negative, since the positive and negative directions are constant realities and not subject to change. Because you have them going the other direction doesn't mean that they've been changed, but rather you have defined the movements in Mach 3 incorrectly

I'd strongly encourage you to correct the axis designations in Mach 3.

Now, it IS possible to maintain the configuration you currently have and modify the post to correct this issue. It's not an easy modification as it effects more than just one axis as well as arcs

[charlieuk]

cool thanks for that so I have found that and changed the direction of y so y positive is going away from me. I still have the home position at the furthest away point so would it make sense to change that to be the other end now?

[LibertyMachine]

Sorry for the delays in responses. Apparently the forums decided to stop sending me notifications..

It actually is completely irrelevant WHERE your home position is set. As long as your machine can home out reliably, you are good to go. Set it where you like and just set your WCS in Fusion accordingly

[charlieuk]

no worries mine stoped sending them too.

 I have changed it around and got it all figured in my head however fusion is now giving me other headaches!

I have been using fusion on a friends cnc that uses nc studio and i was getting everything working fine. Like i mentioned earlier this is the first time i have tried to use fusion on my own cnc that runs mach3.

i drew a file and went to cut it out and a few seconds in everything stops and my y axis driver shows a fault. i re set everything and tried again and it stoped exactly in the same place and cased the same fault on the driver, i repeated two more times out of desperation and the same thing each time!

i then ran a file created by my surfboard program and it all ran fine.

i then created a very simple drawing of a few boxes on fusion and tried to cut it and that also worked fine.

i then tried the original file and it crashed again

so i rew drew the original file in a slightly different way and then that too also crashed!!

I'm absolutely lost as to why it is doing it and very frustrated too considering its such a simple thing!

the two files that fault my cnc are bellow .

[daniel_lyall]

Can you test the two file attached they are in the zip file attached.

Also can you post your mach3 config file. I will post a screencast soon showing where it is.

[daniel_lyall]

the config file's name is the name you click on to start mach3, it will make it easier to find your problem.

[charlieuk]

Sorry was too late last night to run the machine but tested booth this morning and they booth worked fine!

what's your secret!

was I just trying to running it to fast, its only cutting polystyrene so was trying to speed things up. 

I think I have attached the correct file you asked for

Many thanks for your time

Charlie

[charlieuk]

i realised i had got a few of the dimensions wrong on the part so re drew it from new and once again it stoped.

what ever you did solved the problem!

[daniel_lyall]

Are you sure the velocity and Acceleration is correct, your X is 10000 velocity with acceleration at 80 that's .8% of velocity.

In general config you have ij mode set to Absolute it should be inc. 

does the below image come up when you hit reset 

All my tools are set to the max speed of my machine what's a lot less than what you have set, you may well be getting a stackoverflow what's you computer not keeping up with the gcode,

What is the controller you are useing parallel port, ESS, pokeys so on.

[charlieuk]

I'm very much still learning about everything so I'm not sure that I have it set up correctly so I'm open ears on what I should be doing!

I don't get that message when it faults, it just comes to a stop and says there is a emergency e stop on mach3 and a red light flashing on the y axis drive.

I'm using a cs Labs  CSMIO/IP-M 4-axis Ethernet Motion Controller

Many thnaks

[daniel_lyall]

It's more than likely a over speed or loss of position error.

Try haveing the X,Y and Z velocity all at 2000 units/min and the Acceleration at 200 10% of velocity, then try your files what fail again, if the files that fail work the problem is X was going to fast for Y to keep up.

Mach3 works on time of flight, all axis that are commanded to move must meet at at the next move at the sametime 

if you have X100 Y50 and the next move is X150 Y100 if the axis don't get to X100 Y50 before one of the axis moves to its next position it loses what the missing Axis missed it's target by, and it never catches up and it get worse.

[charlieuk]

ok great i will try this, im assuming this is in the mach 3 config file?

[daniel_lyall]

Yep Config - Motor tuning 

If this works, you will be able to go faster again, by just changing the velocity and acceleration on the axis you wont to go faster, with a couple of test you can do to make sure everything is happy.

What is running a engrave toolpath with at a min 1000 moves in any axis, and measuring if the axis has gone back to it's start position

if it does after a 1000 moves or is 0.001, then you run it again and it's within 0.001 +/- 0.001 then you run it a 3rd time and it's the same.

you can increase the velocity and acceleration again and just rinse and repeat to it fails then go back to where it's good.

Or just do the next easy thing get a better controller.

[charlieuk]

a bit of a success today. I did as suggested and tried lowering the velocity and acceleration and managed to get it to run.

I tried lots of combinations however I found that if the acc. was above 20 it would still cut out. I managed to get the velocity to 5000 but the acc. had to stay and 20 or there about.

sorry I didn't quite understand the test you were saying to do.

Is 5000 now my top speed?

when I cut my paddleboard using a different program to create the file and which are anything up to 17' long I run the machine at about 8000mm/min cutting foam for anything up to 8 hours  I did find occasionally it did stop in a similar way however not always, so maybe that was linked to this too. However will this mean its going to take a lot longer now with this new setting?

The motion controller I was lead to believe certainly on a diy machine level was a fairly good one so I don't think there should be a problem there, I think the original motor set up was something that was calibrated by the drivers I think although saying that the x is a different drivers so I forget how we did that.

[daniel_lyall]

All controllers have a point where they can fail you controller is one of the better controllers, with your surfboard program it will be doing a lot of 2 Axis moves so any error is tiny to no error.

One of Mach3 down fulls is 3 Axis moves everything has to be perfect for it to work as it should.

Doing a engrave toolpath with about 20 letters has many 100s of moves in 3 Axis at the same time, if there is a problem the machine will estop or finish and not get back to work zero, if everything is perfect with the machine it will go back to it's start position.

you can set up another profile what you can use with the surfboard program to go flat out.

If the speeds are fine with that there is no problem with 2 axis moves just 3 axis moves, the engrave toolpath confirms that in a few minutes so if you have a speed set at 4000 mm/min and it work fine, that speed is fine with 3 Axis moves, if you have it at 5000 mm/min and it fults with a G code from fusion and the surfboard program is fine, it's the 3 axis moves.

I have the same problem a 2D (2 axis moves) cut I can go stupid speeds, a 2.5D cut (3 axis moves) I have to slow way down.

Does your machine have stepper motors or servo motors.