I obtained a new rough swage block recently and am wondering on the best way to polish it up. There is a lot of slag left in the groves. I don't have access to a milling machine. Is there a quicker way then hand filing? How smooth should the surfaces be?

can you get an angle grinder with a flap wheel in there?

The advice depends on what tools you have available and your skill with those tools. My preference is a 4 or 4.5 inch angle grinder with a grinding wheel, however using a small grinder requires a light hand and experience so that you don't hurt yourself or gouge the swage block.

For cleaning up swage blocks are as mentioned above a 4.5" grinder with a worn wheel so the edge is nice and round works well. You have to feather the grinder on and off because you can damage the block in a hurry. Hold the grinder at an angle to the axis of the groove and it will give you a smaller diameter than the wheel diameter but larger than than the radius on the edge. The other tool that works REALLY well on ladle shapes and for refining the grooves is a Carbide burr in a die grinder. The Solid Carbide burrs are expensive but they really remove metal quickly and controllably, you do still have to be careful not to over do it though. Wear a face shield when you are using a burr as they just spray metal chips. The ones I find most useful are cylinders with end spherical.

The other tool that can be usefull are curved cold chisels which can be used to remove lumps.

Thanks for the info. I have a 4.5" angle grinder with several wheels and have axcess to a die grinder. The straight angles should be no problem. It was the half rounds I was mainly concerned with getting to the right diameters. It sounds like patience and a light touch are whats needed here. The light touch I have, patience is sometimes in short supply.

For the radius parts look into flap wheels in a die grinder. These are really easy to blend with, and won't gouge like a hard grinding wheel.