I use “freeze your nuts off” with barrels that won’t come off. It shrinks the metal and has penetrating fluid that helps. I’ve had barrels that wouldn’t budge with a 4ft cheater bar. Then I sprayed it with the freeze your nuts off and could almost unscrew by hand.I am restoring a South Bend 9 and work has stopped due to a stuck reversing gear. It loks like no maintenance was done since the machine was made in 1947. Everything but the final gear on the shaft has disassembled but that gear needs to be pressed off. A mechanic friend tried with his 20 ton press - dyidn't budge. I took it to a local machine shop and they stopped trying when the pressure was nearing a breaking point.
I have to get this apart. It drives the entire gearbox and screw. I can't afford for it to fail. Any ideas would be greatly appreciated.
Shrink the shaftwith the freeze or swell the gear with heat from a torch. That’s all I can think of besides breaking it and making another if none are available. Good luck