Precision drill jig for tiny cases

grabcad

Hi Folks,here is a drill jig for a case (car key size enclosure), maybe useful for somebody. Made for the pilot series of an small device and works very well. You can't tell a CNC machined one from this. Here i want to share the concept:Purpose:Jig for precise drill patterns in a tiny case.Case type:OKW minitec (meanwhile out of production) injection molded ABS. Other cases needs a different case holderDrill guides:High precision boring bushes (DIN 179 A / ISO 4247). Pressed in holes made during 3D design.Concept:One case- and a bushes holder. The latter is designed as massive consistent block for best possible precision and minimum (thermal) distortion during 3D printing. Features:- compact, lightweight- easy case insertion- easy cleaning- ejection holes on case edges (also used for inspection)- holes works as tolerance compensation (if any) too- mountable on a machine vice - separate holder and drill template - independent change of case and drill pattern3D 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 nearly perfect. 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): TrinckleBusches (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.htmlMädler (alt. source):https://www.maedler.de/product/1643/1629/51/bohrbuchsen-aehnlich-zurueckgezogener-din-179-aMounting screws:M4, out of the drawer