There have been a few threads discussing this... Iirc, the last I read said the nozzles now are eh'd. I don't think any that we use are edm'd anymore but I hope I'm wrong. Used to be the best nozzles were edm'd then barely eh'd to clean up the holes, not so much for increasing the size of the hole. I'm going off of older information so hopefully something has changed since. A concern with eh machining was if the media were to flow through one more holes with less restriction then any others, it could cause inconsistent sizes of holes within the nozzle.