Precision drill jig for tiny cases

grabcad

Human: Hi Folks, here's a drill jig for a case (car key size enclosure), possibly useful to someone. Made for the pilot series of a small device and works incredibly well. You can't tell it from a CNC machined one. I'd like to share this concept: Purpose: Jig for precise drilling patterns in a tiny case. Case type: OKW minitec (no longer in production) injection molded ABS. Other cases need a different case holder. Drill guides: High precision boring bushes (DIN 179 A / ISO 4247). Pressed into holes made during 3D design. Concept: One case- and one bushes holder. The latter is designed as a massive, consistent block for best possible precision and minimum thermal distortion during 3D printing. Features: * Compact and lightweight * Easy case insertion * Easy cleaning * Ejection holes on case edges (also used for inspection) * Holes work as tolerance compensation (if any) too * Mountable on a machine vice * Separate holder and drill template * Independent change of case and drill pattern 3D printing process: High precision SLS prints, bolted together. Tools list in production: * Cordless drill * Drill bit * Vice Results: This combination of bushes and low tolerance commercial 3D printing services works almost perfectly. Provided model: Plain 3D model without a drill pattern (bushes holes). See pictures for an existing pattern. Additional holding posts are made as cut away 's and folded in an otherwise empty area, but were not used in practice. Part and printing sources: * 3D printing (SLS): Trinckle * Bushes (incl. cad models): Norelem https://www.norelem.de/de/en/Products/Product-overview/Flexible-standard-component-system/Drilling-jigs-Drill-bushes-Jig-elements/Drill-bushes/Cylindrical-drill-bushes.html * Mädler (alt. source): https://www.maedler.de/product/1643/1629/51/bohrbuchsen-aehnlich-zurueckgezogener-din-179-a * Mounting screws: M4, out of the drawer