My current project for meat is getting this slicer back into proper shape. I bought this decent slicer from a shop that's closing. It's a small slicer but it's perfect for what I need. However I'm having a hard time figuring out how to take the blade off? I have a screw in the back which seems to be part of the blade holding system. Also there is a round "bolt" on the front with two small holes in it. I notice there are marks where is seems someone has used a screwdriver/hammer combo to turn the bolt. I have unscrewed the screw in the back but this does not free the blade. I'm worried of doing anything to damage the round "bolt" on the front. Any ideas?