Well, I am having no luck in holding the router spindle in vice to remove the spanner nut. I am not much of a gearhead so ideas are welcome. Below is a summary of what I have tried with no luck. Oh! I did use penetrating oil as well.
I am trying to hold it with the two 66mm collars as shown below - collars and shaft are one solid piece. The bearings are on the outside of each of these collars.
Spanner nur socket is homemade but fits perfectly.
After above did not work, I tried wrapping a bicycle tube around both collars and switched wooden jaws with steel ones on the vice but still no luck. The spindle rotates. Tried selectively heating the socket and the spanner nut through the gaps between pins (with heat gun) but no enchilada.
I have spanner wrenches coming today . One could go on the very top nut with two slots (top arrow in pic below). It should helps stop the rotation, but not sure which one of the two would loosen first. If the top collar loosens, then maybe after removing the top bearing, I can shift the spindle in vice where part of the lower collar is outside the vice and then I can place the spanner wrench on that part.
Imran