Hand Dressing a Hammer Head

[Dom]

I need to dress a new hammer head. I first tried to break the sharp angles with a angle grinder but I'm far from being an expert with that tool. I have a hard time visualizing exactly where the disc will grind on the hammer's face so my grinds are more random than I would like.

It has helped but the hammer still leaves marks. What can I use if I want to finish the job manually and get a nice smooth surface? A file? Some kind of sanding paper?

Thanks for any suggestion.

[arkie]

I use a 4 1/2" angle grinder with a grinding disk, usually about 80 grit to begin with.  Start working in circles, then back and forth over the crown; repeat.  DO NOT overheat when grinding...I grind quickly and stop when it's uncomfortable to touch...let it cool...any hotter and you run the risk of removing any temper.  Then work your way down in grit size, using something such as a flap disk, finer than the 80 grit disk, say 100 or 120.  You can finish up with one of the paint removal scrub disks, like a Norton blue one on the grinder.  That will get it pretty shiny.  Just DON'T overheat on any grinding.  If you have a belt grinder, you can work down the surface like bladesmiths do.  You can hand finish it with very fine sandpaper, like 400 or 600, if you want a really polished finish, but that's not necessary.

[Glenn]

This is one place where modeling clay helps.

Make an impression from a known hammer face as a negative. Then use that impression to make a positive to see what the finished face should look like.

 

When making your own hammer face, use the modeling clay to make the impression and check your work. The clay will show you where you need additional work. You are used to seeing a positive, so the negative is different and you will find you look at it in a different way and see things you would have missed.

[Frank Turley]

I use a disc sander and sometimes my hand held belt sander (Makita; 21" x 1 1/8" belt). The belt sander can be set at the slower speed. After using the finer  grits, I often finish polish with my Scotchbrite wheel. I tell folks the face should approximate the curve of an ol' pocket watch crystal.

[AdamG]

I just hold the hammer face to a slack portion of my belt grinder and make a circular rocking motion, moving up in grit from 36 to say 120.  Pretty forgiving unless you get your hand on the belt!

[Glenn]

Many topics have been discussed before. In chasing down references posted on another thread, The cow pie analogy of hammer dressing by Shane Stegmeier February 6, 2008 showed up.

As they say, pack a lunch and a cold drink, and do a little reading.

The cow pie apology is very helpful to get people to understand how the steel moves under the hammer. Hit a cow pie with a stick: it divides along the line it was struck. Hit it with a brick: and the pie flys mainly away from the long sides of the brick, and less along the short sides, and only a little at the corners. Drop a square paverstone on it: and the pie will fly away from the sides, and a little bit at the corners. Drop a bowling ball on it: and the pie flys equally in all directions.

The things you can learn by reading IForgeIron. (grin)

 

You can read more at Hammer Dressing and Cow Pies.