Eraser tool with specified width for laser cutting tabs/bridges

Rhino Rhino for Windows
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1

Hi there,

I believe I’ve searched all of the forum for this but didn’t find it. If this has been done already please let me know.

I laser cut a lot of small wood laser parts and I want them to stay attached to the board so that they don’t get lost. The client can then tear them from the board easily, like cardboard parts for a new boardgame. To do that I create “tabs” which are small pauses (~0,5mm) in the laser cutting path. See here for an example : Applying tabs in laser drawing

The way I do this is by creating a circle on the path, and using the trim command to cut what is inside the circle, then delete it.

I wish we had an “eraser tool” with a specified width, so that by simply clicking and moving the mouse over a curve, it would delete a portion of this with a specified width. I’m thinking Sketch/Offset and cap/Trim.

Is there any easy way to do this?

See below an exemple of a tabbed laser cutting path.

image
image699×771 7.42 KB

2 

import Rhino
import scriptcontext as sc
import rhinoscriptsyntax as rs

def reparameterize_curve_to_length():
    curve_id = rs.GetObject("Select a curve to reparameterize", rs.filter.curve)
    if not curve_id: return
    curve = rs.coercecurve(curve_id)
    
    # Reparameterize curve to its length
    length = curve.GetLength()
    if length:
        domain = Rhino.Geometry.Interval(0, length)
        curve.Domain = domain
        rs.Redraw()
   
    return curve_id

def pick_points_and_trim_curve(curve_id):
    points = rs.GetPoints()
    if not points: return
    
    w = 10
    w_half = w / 2.0
    curve = rs.coercecurve(curve_id)
    
    # Trim intervals around each point
    params_to_trim = []
    for point in points:
        param = curve.ClosestPoint(point)
        if param:
            params_to_trim.append(param[1] - w_half)
            params_to_trim.append(param[1] + w_half)
    
    params_to_trim.sort()
    trimmed_curves = curve.Split(params_to_trim)
    if trimmed_curves:
        rs.DeleteObject(curve_id)  # Remove original curve
        for seg in trimmed_curves:
            if seg.GetLength() > w:
                sc.doc.Objects.AddCurve(seg)  # Add back valid segments
        sc.doc.Views.Redraw()

def main():
    curve_id = reparameterize_curve_to_length()
    if curve_id:
        pick_points_and_trim_curve(curve_id)

if __name__ == "__main__":
    main()
2 Likes
3

Late reply but it seems to work, thanks !