this is the script i wrote
mods.magneticraft.Grinder.removeRecipe(minecraft:log);
mods.magneticraft.Grinder.addRecipe(minecraft:log,minecraft:planks(6), 0.0, 100, true);

this is what i get when i open a world
Error executing {[0:crafttweaker]: Magneticraft.zs}: Not supported yet.
just wondering if this works yet or if i did something wrong with the script

I'm not an expert in zen script but those lines seem wrong, try:

mods.magneticraft.Grinder.removeRecipe(<minecraft:log>);
mods.magneticraft.Grinder.addRecipe(<minecraft:log>,<minecraft:planks:6>, <minecraft:planks>, 0.0, 100, true);

Also I think you can use and empty second output with:

mods.magneticraft.Grinder.addRecipe(<minecraft:log>, <minecraft:planks:6>, <minecraft:air>, 0.0, 100, true);

i figured it out thank you