opening karchis ??

Just get a fine file and file a score mark and you ar fine.'

I just put the amp in a wash cloth and put my teeth on the indent and put pressure on the top and it breaks. I have only ruined 3 amps doing this!
amp opener.......i think karachis are a bitch to open... thats my opinion though
OK. I finally figured it out and stopped breaking my karachi's. Use a nail file. Some are more course that others but all will work in time. Angle the file and just keep going back and forth. Make sure you sand a whole side. Than stick the amp in a pen cap and slowly try to seperate at the sanded area. If it won't break off easily, than you need to sand more.
I bought a triangle shaped file from Home Depot that works great! I file around the entire amp, and it pops off without any pressure.
Buy a small hacksaw blade,, like the ones you use in a miniture hacksaw.

Use the blade to cut a small groove around the neck ( you really only have to scratch it)

Than just flick the top off