Reverse engineering

Here is demonstration of some reverse engineering work that we recently carried out for a client. We were given a broken part that had shattered and had been glued back together. Some of the broken parts were completely missing and the part was not functional.

We used laser scanning to quickly create a 3D model of the broken part as you can see in the first model. The pictures below show some of the unedited scan data.

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As you can probably tell, the scan data alone is not sufficient to create a new part. There are pieces missing, the alignment of the glued parts isn’t perfect and the surface finish and features of the part are not ideal. By taking many scans we are able to capture more data and make a more accurate model. For this part we used 7 scans at different angles to capture most of the features.

Using mathmatical curve analysis techniques we are able to predictively model the parts that are missing.

The first 3D model below is the result of combining all 7 scans and some basic processing.

The second model is the result of completely rebuilding the individual features of part. During this process it is important to pay close attention to the deviation of our part from the scan data to ensure that tolerances are kept as close as possible where appropriate. The result is a parametric model with a perfect surface finish. Each feature is now easily adjustable and can be changed or modified precisely if necessary. With this example we want to make a new part so we have made some slight adjustments from the scan data to compensate for the wear and tear on the old part.

We can now send the second model to our 3D printer or we can use one of our CNC machining centres to make the part from any number of other materials.

  

Here you can see the original part and next to it, the reverse engineered part that we quickly 3D printed.

After testing the part we found that it functioned correctly but the fit was not perfect. With some minor sanding we improved its fit and made operation smoother. When we had the perfect fit we laser scanned the printed model and generated a new and idealised parametric model for 3D printing.

Below is the final part that is the perfect fit.