3D Model Laser and X-ray CT Scanning Projects
I'm often asked "What is scanning used for?".
I use 3D laser scanners and X-ray CT scanners to create dimensionally accurate CAD models of physical objects (parts) and to perform dimensional analysis and non destructive testing (NDT). The parts generally fall into one of two categories; old stuff and new stuff. The old stuff usually involves CAD modeling and the new stuff dimensional analysis and/or NDT. The following are a few examples:
A foundry making investment cast fire sprinkler heads needed to increase production on an older model head. The foundry wanted a multi cavity mold that would produce wax patterns that were identical to the ones produced with the old single cavity mold. During the development of the original head, the single cavity mold had been modified based on customer requirements and the parts coming out of the mold were significantly different from the old drawings. I was able to laser scan one of the wax patterns and create a solid CAD model that replicated the pattern precisely. The customer then scaled the model for shrinkage and cut a new multi cavity mold. According to the customer, "The parts from the new mold are indistinguishable from the old".
A contract manufacturer specializing in aircraft structural components needed to machine a replacement for a 4' long section of cracked longeron from a commercial airplane. The standard procedure was to use a profile mill to machine a replacement by tracing the profile of the old longeron. The manufacturer had gotten rid of the ancient profile mill in favor of new CNC equipment and had no way to machine a new longeron without a CAD model. I was able to laser scan the cracked longeron and a plaster cast of part of the longeron still in the aircraft and then create a solid CAD model of the replacement with an integral doubler (splice). The customer machined the replacement part and "it dropped right in".
A contract manufacturer machining a family of parts for a long time customer damaged a functional gage for one of the parts. A new gage fabricated to print produced parts that weren't functional. Investigation found that many of the other functional gages weren't made to print even though parts made to them were functionally acceptable. I was able to scan and model the gages to enable the shop's drafting department to produce accurate drawings and to aid machining of new ones in the event of another mishap.
A firearms manufacturer cracked a set of forming dies used on one of its most popular pistol magazines. The dies had been tweaked to provide parts that functioned reliably and did not exactly match the CAD models originally used to make them. Prior to the accident, the manufacturer had already had me scan and model a magazine in preparation for designing new and improved dies. Unfortunately, the accident accelerated the project and necessitated a more direct approach. I was able to scan and model the old dies so that new ones could be machined immediately.
As part of a reshoring effort, an injection molding company needed to design and fabricate molds for a sporting goods item. The original molds were made to match hand carved prototypes and no drawings or models were available. I was able to laser scan and model one of the parts produced overseas so that new molds could be produced here.
A manufacturer of high end kitchen utensils was having problems with unacceptable overmolding on one of its product handles. The problem was caused by mismatch between the parts coming out of the primary molds and the overmold tooling. I was able to laser scan and model some parts from the primary molds. The CAD models included the shrinkage and warping found on the parts. The models were used to re machine the overmold tooling to precisely match the parts. This has since become the manufacturer's de facto method for debugging overmold problems.
A medical device manufacturer wanted to shorten the development time on a new delivery system. The system was an assembly of ultra precision injected molded parts with extremely small features. Previously, similar systems had required many iterations of mold tooling designs to achieve the desired product quality. Using X-ray CT scanning I was able to create very precise, ultra high resolution CAD models of the as-molded assembly components. I then 'assembled' the components in CAD and used fly throughs, sections and interference checks to determine the required modifications and eliminate many mold iterations.
The above are only a few of my scanning projects, but perhaps they give some idea as to "What is scanning used for?". For more details.
