In Praise of the Engineer’s Hammer (aka a Lump Hammer)

While I was at David Savage’s workshop I was delighted and surprised to see he used a “lump hammer” for assembling casework.

David brought the hammer to my workbench when he helped me knock together my dovetailed tool chest carcase for a class. And when he saw me smile hugely at the lump hammer (instead of recoiling in horror, which is what I think he was expecting), he told me something I didn’t know.

The lump hammer was one of Alan Peters’s favorite tools, as well.

I’ve carried one of these heavy hammers or one with wood faces (which I call “Mongo”) to classes where beatings were required, usually classes in tool chests or workbenches. Lump hammers look like they would destroy a carcase, but quite the opposite is true. They are gentle giants.

David and I are not alone. Richard Maguire, the English Woodworker, has written about his love affair with “Lumpy” on his blog here. Same with James Watriss. Now before you go looking for a “lump hammer,” read on.

Here in North America, it’s called a sledge, blacksmith or engineer’s double-face hammer. But none of those names does the tool justice quite like “lump hammer.”

I like one with a head that weighs between 2 lbs. and 2-1/2 lbs. (in metric land, look for a 1,000-gram head) with the tool’s total length about 10-1/2”. You might have to cut down the handle; this will improve its balance and finesse.

And here’s the good news: These sledgehammers are incredibly plentiful and cheap. Check out what’s on eBay today here.

I have an old Japanese one, and I recently gave it the “Seth Gould” treatment – charring the handle with a torch. You can read more on this technique in the April 2015 issue of Popular Woodworking Magazine.

Next time you see one of these tools at a flea market or used tool sale, pick it up and see how it feels in your hands. You just might just want to take one home.

— Christopher Schwarz