Suppose it can be a bit confusing. If you're using the allen key from the back of the spindle on the RH (drive-side) pedal, then you would be trying to turn it clockwise to loosen. From the pedal side (front), that's counter-clockwise or "lefty-loosey".
I never use an allen wrench on pedals, so didn't realize you were breaking those. You really can't apply much torque with an allen key without rounding it off or breaking it, as you found out. As Alienator said, a big pedal wrench is the way to go. If you don't want to invest in tools, just use your LBS. Hopefully they will do these little jobs for you while you wait, with a minimal or free charge. Plus you can learn a lot just watching....like grease on the threads
hehe, it didn't dawn on me what you said in your 1st post, just cause I was so mad at this . I'm getting another 15mm wrench, and I should be all set (although now I've tightened it soo hard that it will be fun getting it off). Thank you for helping me through my brainfart .
Some good suggestions here, but my first tool for a stubborn pedal is a machinists' hammer. It may be a scary thought to some, but have found the impact from a modest tap or two on the wrench is usually all it takes to loosen stuck threads. Hold the wrench and crank arm firmly with your other hand while tapping, or get a helper. Use caution of course. If a few reasonable blows doesn't do it, then would try penetrating oil overnight, followed with a repeat with the hammer taps.
1. Place U-lock through frame to brace crank. (Not recommended with CF frames)
2. Heat crank end near pedal with electric heat gun.
3. Use Park Tools Cone Wrench (15/22 mm) to twist pedal in correct direction. Backup was with a hex-head socket and a breaker bar with a 3/8-inch drive. Extra leverage on breaker bar if needed would have been from a piece of 1-inch PVC pipe.
4. Place Anti-Seize compound on threads of replacement pedals before installing. Better than any grease out there for thread protection, won't dry up or evaporate.