what i sould have said was a prybar
the caliper was still attached the the hub and the outerpad still in.
what i was doing was pressing the pedal to move the piston out so i could move it back so to give it some movement to free it up and i was using the flat part of the prybar to move it back into the housing.
what ive discovered is a heavy bit of corrosion on the piston under the dust sealwhich has been stopping the piston going back in and hence sticking on.
with me pushing the pison back in part of it has stuck fast, hece the break.
but looking at the condition of them its not surprising it broke
the downside, with my shift pattern its going to be another 2 weeks till i get her on the road