[Mark Roberts]

Hello, does anybody run rust inhibitors in the water of their wire EDM machines? I know that there are a few products out there. Some claim to eliminate scale on the insides of the machine as well with no effect to the conductivity. Any help would be appreciated.

Thanks,
Mark

[ltkettch17]

I only used a rust inhibitor once. Be sure you read the label about how much to put in per gallon. I used too much and it totally screwed up my conductivity. I had to replace all the water, filters, and resin to get things back to normal.
The place I'm at now does not use an inhibitor. They mostly spray the workpiece before setup. Works okay on everything except the wired surface.

hth.

[Medm]

Rust inhibitors used to be recommended by some edm builders, but are now no longer recommended.

From my own experience with them, they are mainly water soluble oils that leave a sticky film on the machine and parts if the water/electrolyte is left on to evaporate (overnight). The film has to be removed to maintain accuracy and a proper working environment. It seems to me that algae forms more rapidly with a rust inhibitor present.

In summary, the machines are built using stainless steel piping, which does rust a little on the welded joints, but not significantly. If you want to cut mild steel or other materials with iron present, just remove them from the machine as quick as possible after cutting. If the piece is to be left overnight just give it light coat of oil before cutting.