reducing the amount of taper in an edm hole

[igor sawon]

Experimentation with on, off, ip c & has shown improvement in the amount of taper found in a 1.8 diameter burned hole thru a 1.5mm. thick piece of nickel alloy material. However the amount of taper is still measured at approx. 0.05mm total taper over a distance of 1.50mm. Any reccomendations from operators of K1CN hole poppers on their sucessful reduction in hole tapers would be considered.

[Terry Meyer]

Also check your Vitol fluid with a refractometer.
The reading should be 10 brix for Vitol KS. From this starting point if the hole still has taper add DI water to thin out the fluid, and try again.

If you are breaking out the bottom, typically the hole size gets tight at the bottom. Try blocking the bottom with a scrap piece if possible.