why would anyone....
 

..use red loctite on the inside of a hard brake line fitting? Despite lots of pb blaster and heat, I twisted the copper pipe clear off. Once out of the caliper, I continued to heat the fitting and as I suspected, red goo oozed out between the copper pipe and fitting. That explains the red nail polish someone dabbed on the caliper. Time to start shopping!

Dang, that's harsh. N ot much to do but replace. I did buy some brake lines for another project and did notice they had a blob of blue locktite on the threads. But the blue is removable!!!