TH crane burning smell showed again this morning. It appeared after 1-1.5 hours of continuously using during the F308 flasks moving in TH.After a certain time of using I think the brake gap is reduced because of  thermal expansion. The main hoist and brakes work fine still. We knew these brakes gap are tight especially on west side. So, It is not surprised that this burning smell appeared again. It does not affect the safe of crane use in my view. But, The life of this brake assembly could be affected.  I would like everyone know this issue. We may need to consult Gordon crane as well. Maybe, The gap should be increased up a little bit.  On this Friday, I will use crane to transfer 30K lbs shielding blocks. It will be a good test on crane main hoist again.