OUR BLOG

08 Apr 2016

The secrets to moulding perfect pens!

Behind every well moulded pen body, lies a perfect cooling mechanism within the mould. Sparkonix EDM Drills are leading the way in core pin drilling applications, which is critical to perfecting the cooling mechanism in pen moulds. Plastic Pen moulds have multiple cavities and come with a cooling assembly. The quality, in terms of strength and finish of the pen body, is a direct result of the effectiveness of cooling mechanism for the moulds. Typically, pen and pencil bodies need a deep hole with very small diameter for the core pin to enable faster, efficient cooling of the mould. Sparkonix EDM Drills are trusted by leading pen/pencil mould makers/manufacturers for the critical core pin drilling process.

Core pin drilling in moulds
The core pin drilling for pen moulds needs a 2.0 mm + diameter hole over a depth of 250-300 mm. The fine tolerances and narrow wall thickness in the mould means a very high level of precision in drilling the core pin holes. The slightest deviation in drilling can adversely affect the quality of core pins and ultimately the quality of final product.

The Challenges
In the core pin drilling process, insufficient flushing often heats-up the core pin and can lead to its deformation. This also affects the perpendicular position of the electrode drilling the hole which must be strictly maintained over the entire drilling depth.

The EDM Generator
Sparkonix has mastered the EDM Generator technology for drilling deep cavities. Whatever be the work piece material, hole oversize can be achieved within required tolerances. Sparkonix  EDM Drills offer the same consistency for drilling length of up to 300 mm.

The right pumping pressure
When Drilling very deep cavities, the disintegrated powder has a tendency to accumulate or get stuck in the hole leading to its deformation. The pump capacity and design of flushing mechanism is very critical to precision EDM drilling. Sparkonix’s EDM Drills uses a specially designed plunger pump that provides the most accurate pressure for water used in flushing. The pump is manufactured in-house with Sparkonix stringent quality benchmarks and provides far better consistency in pressure when compared to conventional pumps. A well-designed bypass mechanism with pressure relief valve completes the flushing cycle.

pranav@yuk