If they are old razors made a number of years ago then the edge has oxidised and become weak. This leads to microchipping.
You need to use the 4000 hone and wear away the oxidised steel. The way to do this is to put 25 laps on the 4000 and then 5-10 on the 8000, then check for microchips. Do this until the microchipping stops. On the wedges and any other razor that is old and oxidised I put tape on the spine until the microchipping stops. The amount of pressure I use to remove the micrchipping on the 4000 is 1-2 lbs. When the microchipping stops then I go back to the 4000, without tape, and use a light pressure for 10-15 laps to establish the proper angle. By this stage you are almost done and also almost overhoned so be watchful for a wire edge.


Hope this helps,