Any tricks to copy a real object to then laser cut to original size?

I have a part of an RC car which is likely to be prone to breaking(shock tower) and thought it would be a good idea to get a 2D drawing of it for laser cutting if needed. But I tried putting in on the flatbed scanner and the offset of the light with the sensor makes a mess of the image.

Any other technique others have used to create vectors of real objects for laser cutting?

Doug

Use a camera instead of scanner? That way you can have more control over the lighting.

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I decided to stop using the scanner in the all-in-one printer and get my Epson flat bed scanner out. Installed the software in Ubuntu and started playing around. B/W, no paper behind it, lid up/down, color, etc. I got the best results using color with the lid up.

Then I imported into LaserBurn and then Inkscape and tried edge detection but it looked like too much ‘other’ things were getting in the way.

So I brought it into Gimp and started cleaning it up with an eraser around the entire shape and in the holes. In hindsight, I should have made as mask layer(white or black) and put the layer behind the image but active and then start cleaning it up. I changed the diameter of the erase brush to match diameters of holes and curves so it would have made a quite clean mask. But because I didn’t do that, when I inverted the color and started working with it further there were lots of spots and imperfections to clean up. Gawd, probably would have taken less time to just go over it all again and make the mask but I kept at the tedium can cleaned it up pretty good.

I turned off everything but the black mask layer and exported it as a PNG and imported into inkscape where I did edge detection, and then turned on nodes view so I could find the little buggers I missed in gimp. I still need to measure a few things to make sure I have the scale correct.

Saved that as an svg which I imported into LightBurn which looks like it’ll make a very nice laser cut part. If I need it. LOL

Well, it looks like Inkscape edge detection was giving me 2 vector lines for every edge. I could not get it to present one vector for each edge but LightBurn does a great job doing that. I could not get node editing to work in LightBurn so I exported the SVG and did final cleanup in Inkscape before sending back to LightBurn.

Hi Doug, I had to copy many objects in my business. I usually use an old version of coreldraw, but inkscape is equally useful.
Most of the time it has been more practical for me to redraw over a scan of the original object than to use automatic vectorization. Mainly for this reason that you comment, the poor quality of the image, that even having high resolution let loose having shadows, halftones at the edges etc etc
I have discovered that I waste less time redrawing than cleaning the result of a automatic vectorizer

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Thank you Otromar. In 3D I have often brought an STL into OpenSCAD, set it to translucent and started building the part from scratch. When I get better at drawing I probably could have wipped out the part in 1/4th the time it took to clean the scan up.

In hindsight, it’s really the hole locations where where the most important part of the copied design so it really would have been quicker to just place proper circles and hand draw the outline.