Posted by Joe Lorenzino [216.197.153.67] on Tuesday, February 25, 2014 at 22:16:37 :
In Reply to: Removing taper pins? posted by Sherman in Idaho [72.47.153.112] on Tuesday, February 25, 2014 at 16:40:41 :
I've run into the same problem on many old printing presses we used to service. Our method was to use a tig welder to build up the large end of the pin until it was 1/4" or more above the surface. Then, either weld a small slide hammer to it and pull it out, or weld a nut on with enough room underneath to get a couple of screwdrivers/pry bars in from opposite sides.
I like to use a 312 Stainless rod for this, as it has more "toughness" than most other tig rods we keep at work. Welding also tends to shrink the pin a little, and warm up the casting, which helps in removal.
This has also been done many times with a stick welder using an ArcTec 265 "Unichrome" rod. If I have to use the stick welder, I usually clamp a nut in place over the pin to act as a guide for striking the arc. Weld up through the centre of the guide nut, then remove it when the slag cools. Chip the slag off, and weld on the puller or nut to the built up pin.
Have had good success using both methods, and the pin can be reused in most cases.