Hello all, Aubrey here,
one question in a Grbl workspace(running win 7pro,arduino,cnc shield and grbl 9j. My home is top right) all the test files I have tried to run, run great except they are mirrored backward in the Y direction . The calibration pattern text is backwards. What am I doing wrong and how do I fix it. Thankyou
Sounds like your axis may be inverted.
If you jog using the axis widget do the axes move the directions that they should (left and right are obvious) y up should move the axis away from the front. And vice versa with y down.
If so then you need to invert the y axis. Either by swapping a pair of wires to the stepper motor or changing the config setting. Send $3=2 from the serial port console to invert the y axis. $3=1 to invert X axis. $3=3 to invert both.
Hello Justin, jogging produces correct movements as they should. Issuing commands thru the console also moves them in the correct direction as well. Would changing line numbers $ 130-132 to be negative help or should $23 have to be changed as well. I am miffed at this one snag
130s would not be related. Nor would homing.
Does the 3D view of the rendered gcode look correct when loaded? Perhaps a short video of your screen whilst CP does a virtual job?
The 3d view show correct oreintation, but as you can see from the pen print out all circles and squares are proper dimension only flipped.I am not at my garage right now so can’t shoot a video
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I’m really surprised that jogging produces the correct movements. (i.e. that jogging right in chilipeppr moves the spindle right on the cnc, front/back likewise).
your excellent drawing suggests that something is back to front - whether it is your motor configuration (post the output from $$ here) or whatever.
Re homing, how have you persuaded your mill that machine home (ie 0,0,0) is at the back right (visually/cognitively I have a hard time with home being anything other than front left)? Logically, unless you have set your x/y axis motors to reverse, moving positively along the x axis would cause the mill to hit the limit switch each time. ditto the y axis. so something must already be reversed!
Unfortunately there is no facility in the general CP workspace to flip along an axis (which would resolve the symptoms of your issue, even if not really curing it). This facilityexists in the eagle widget. I have not checked the architecture of that widget but possible it used the rendered gCode to flip rather than take the eagle data and flip that before rendering. If so, it would be trivial to adapt that into the main workspace. @ameen.nihad may know the answer off the top of his head!
would definitely help visualise to see the mill and cp in action at the same time. I still worry that the jogging is working and the milling not. .
Have you ever run a successful job on your CNC? My gut tells me it’s just a config on your firmware that’s off.
Hello Gents, sorry for the tardy response(I was out on the road) but here is all the info i can provide. Please comment on what ever needs correcting , Hello John thanks for jumping in. To answer your question I am still in testing phase of my build and been air milling for now.
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https://drive.google.com/open?id=0Bx2uE6QoQzEiZ2FzTHJyZ3l1TTQ
sorry forgot to add the video files in zip folder
Just FYI using soft limits requires homing to be enabled and limit switches to be present. Homing works by the machine going positive in each direction until it hits the limit switches.
Is this consistent with your setup?
From your video it seems that your y axis is inverted. Could you try sending $3=2 and then rerunning the pen job?
You said you had homing set at back right. Grbl homes to the positive direction unless you apply a mask to $23. Extrapolating from the CP workspace and the movement of your spindle as it traces the pattern the x axis is set so that 0 is on the left and positive to the right. And the y axis is set so that positive is to the front. And 0 to the rear.
This should correct when your motors are running consistently with your controller instructions.
If you have CNC home at max x/y this means that your work home will always be a negative x/y number. This isn’t a problem mechanically but may take some headspace to get used to. I think this is the reason why home for me is always front left. Mirrors my mental geometry axes. Of course CP/Grbl presents things in work coordinates for you so largely it is less of an issue.
For me front left is also the most convenient place for tool changes.
Also are you confident of the steps/mm settings for your axes? Getting this wrong will result in scaling issues and for the z axis potentially broken bits!
If not confident then i’d suggest some simple calibration patterns of straight lines at set intervals. You can do this manually by jogging to a start point of your choice then dropping the pen down to the paper. Then jog 10cm along the y axis. And 10cm along the x axis. Then measure the actual line lengths and adjust.
Before doing that it is a good idea to set the steps/mm value based on your motor specs (steps per rotation) the size and pitch of your screws (if you are using screws) and whatever microstepping settings you are using on your controller board. There are a number of web resources to help you calculate.
Hello Justin, great info, tonight I will change $23 and $3 and get back to you. For some reason the jogging video did not get uploaded into that file . None the less I’ll reshoot after the adjustments. Thanks again for the advice.
You shouldn’t need to change the homing direction if you want the machine home to be back right. Of course all irrelevant if you don’t have limit switches.