Removing Seized Brake Nut

[eck]

Any ideas on how to remove the "sunken" allen key nut that goes inside the rear brake bridge? I've got the brake itself off, but the nut is seized solid. I've tried Magic Spray, and screwing in a long bolt to hammer it out. Am I left with any options other than drilling it out? Ta!

 

[raleighnut]

Try spraying and using a long allen key working it back and forth, repeat every hour or so. Do not use too much force just jer j jer jer jiggle it a bit.

 

[mrandmrspoves]

Screw in a long bolt with a nut and two or free washers on it. Then tighten the nut so that the washers are between the nut and the brake bridge while ensuring the bolt doesn't rotate.If the stuck recessed nut is too near the surface of the brake bridge use a large nut followed by washers between the brake bridge and the nut that is threaded onto the bolt. Should act like a puller. Well worth soaking the area with Plus Gas or similar penetrating oil overnight first.

 

[eck]

Got it out. A few minutes with a hot-air paint stripper, a quick skoosh of cold water, a whack with an ammer, and there we are.
Thanks, mrandmrspoves, that would have been the next step, but I couldn't find a suitable combination of bolt, washers and nuts.