Moves to safety height on each pass?

[peteruithoven]

Currently the drill seems to move to the safety height after finishing a pass before it continues with the next pass (on the same operation). Since the Z axis usually moves very slow this costs a lot of time. Why move to the safety height between passes of the same operation?

[tbfleming]

If the cutter can move to the starting position from the ending position in a straight line without crossing outside the cutting area then it doesn't go up to the safety height. I made this calculation conservative for safety. I limited it to a straight line because path-finding algorithms are pretty expensive.

[peteruithoven]

I'm afraid there is an issue. Maybe something goes wrong when it's exactly the same position? I can replicate it with the following rectangle.

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Settings I used:

{"svg":{"pxPerInch":"90"},"material":{"units":"mm","thickness":25.4,"zOrigin":"Top","clearance":2.54},"curveToLineConversion":{"minNumSegments":"1","minSegmentLength":2.54},"tool":{"units":"mm","diameter":3.175,"angle":180,"passDepth":"5","stepover":0.4,"rapidRate":2540,"plungeRate":127,"cutRate":1016},"operations":{"operations":[{"rawPaths":[{"path":[["M",200.88481,496.91034],["L",545.61369,496.91034],["L",545.61369,660.23486],["L",200.88481000000002,660.23486],["L",200.88481000000002,496.91034]],"nonzero":true}],"name":"","units":"mm","enabled":true,"combineOp":"Union","camOp":"Engrave","direction":"Conventional","cutDepth":"20","ramp":false}]},"tabs":{"units":"mm","maxCutDepth":0,"tabs":[]},"gcodeConversion":{"units":"mm","gcodeFilename":"gcode.gcode","offsetX":0,"offsetY":0}}

If you point me to the peice of code that does this safety height I'd love to help out.

[peteruithoven]

It's probably the safeToClose boolean or the tabGeometry.length on the following line: https://github.com/tbfleming/jscut/blob/gh-pages/js/Cam.js#L411

[tbfleming]

Please use the gist save option in the future; it makes reproduction a lot easier.

Odd. safeToClose == true and tabGeometry.length == 0. It's not entering that condition, which means something else is retracting.

[tbfleming]

Found it. It should ignore tabZ at https://github.com/tbfleming/jscut/blob/gh-pages/js/Cam.js#L419 when tabGeometry.length == 0.

[tbfleming]

Also at https://github.com/tbfleming/jscut/blob/gh-pages/js/Cam.js#L418

[peteruithoven]

Nice! I was just going to mention that it's not the retractGcode part, but the Rapid to initial position part.

[tbfleming]

Good news! It means someone else can read my code :)

[peteruithoven]

Works! That's gonna save lot's of milling time.