these cranks don't have puller threads so generally you just beat them out with a mallet. i have removed some bmx cranks that were similar to these. we are not a bmx shop so we don't do much bmx work. the bike belongs to a kid that volunteers with us once a week. this one is in rough shape. not super rusty but some corrosion is present. it is soaking in penetrant. i have beat on the arms with a deadblow and used an air hammer on the spindle itself trying to drive it out. anyone got any tips?

Profile makes a tool... you might try buying an appropriately sized bolt that engages the spline theads as far as possible and then beat the crap out of the bolt. I know you said you already beat the spindle but I'm wondering how hard you hit it since the end of the spline is recessed in the crank arm. A protruding bolt would allow you to really smack it. The penetrating oil is a good idea and a propane (or hotter) torch might not hurt. Anti-sieze prevents these kinds of headaches when you reassamble.

TM

i have a profile tool but it doesn't fit. i know profile makes a few different tools. this crank is a profile style in the sense of how they attached(no pinch bolts). not sure what they are anymore, too much shoe rub. i have stuck a bolt inside the spindle and whacked it hard enough to bend the bolt. anyways these are on there good. just trying to put on a new sprocket because the old one exploded

Penetrating oil, patience, heat... and a new bolt (might try a grade 8 and see what gives then).
Good luck