Posted By:
T206Collector"With this method there's no tension between the halves as in the twisting screwdriver method."
I have done the hammer/chisel method and it is messy. I have no idea what tension between the halves is created when twisting the screwdriver in the method I recommend. You are simply breaking the seal around the whole outer edge, at which point you can easily lift the top plate off of the bottom plate. And it is clean and quick.
This is for SGC, however. For Beckett you need to do the hammer thing, and for PSA the hammer thing may be necessary as well. Even if you use the hammer thing on the SGC holder, you'll likely be fine, but it seems to me to be more work/effort than necessary.