Mass-produced for small to mid-sized DC motors, disposable moulded commutators offer the end-user low performance and low reliability. As well, it can be difficult for winders to source a moulded/riveted replacement for the commutator they need. In these circumstances, EMCC/Thistle Industries can re-engineer and convert these commutators to high performance, high-reliability, v-ring style commutators. Steel v-ring style cores allow for easy commutator re-fill and repair.
High Grade Copper & Steel Cores
Moulded commutators are often produced cheaply for OEM's using lessor quality copper (alloy 114,105,107) and construction materials. Copper bars are punched - not machined, offering lower precision assemblies.
Bakelite, cast iron, and phenolic compound cores often lead to bar movement and reduced commutator stability. Moulded type commutators are not repairable, so when they fail, they must be replaced or re-engineered into a complete new v-ring style commutator. Our moulded conversion commutators are only built with alloy 116 (high silver content copper) that offers better wear and conductivity.
At EMCC, these types of commutators are re-engineered with high-grade steel - V-ring style cores, bound under pressure that can be reused over and over. Steel cores allow for increased bar stability, better brush wear, and longer life cycle of the entire motor. It also allows for minor repairs should the commutator fail in the future without scraping the whole commutator.
Most moulded commutators run into issues of electrical arching between copper bar segments and from the bars to the core. They often do not have mica extensions between the bar segments at the riser end of the commutator. This allows for dust build-up and arching. The same is true for the end, opposite the rise. Flush mounted cores with limited or reduced insulation extensions allow for the build-up and eventual grounding out.
Our re-engineered V-ring style commutators are manufactured with individually machined copper bars at tolerances of less than .001 thousand of an inch from end to end. Each copper segment is insulated with high-quality mica that extends past the riser end of the commutator. Steel cores are well insulated by mica V-rings that extend past the brush end of the commutator, providing superior resistance to electrical arching.
Many moulded commutators have small diameters and low bar counts. We are capable of re-engineering and manufacturing moulded and riveted (Nippert style) commutators as small as 3" in diameter. The larger the diameter, the easier they are for us to re-engineer. Riser widths, bar lengths, dust grooves, bore sizes, keyways, venting and slot sizes can be customized to suit your needs.
24/7 Emergency Repairs
When failures occur, EMCC has the capacity and ability to work around the clock to manufacture or service the commutators and coils you need. 24/7 production capability allows EMCC to deliver unmatched quality, with the best turnaround times in the industry. Often, coils within 24-hours and commutators between 24-48 hours.