Introduction: UHMW Polymer Carver Deadblow Mallet

About: I make stuff for a living, an Industrial Designer by lifestyle, education and interest. Always up to learn something new and keep my skills on the cutting edge.

In this Instructable, we set our eyes on a simple but very effective tool, the humble leather working mallet. I punch hundred’s of holes each week to slide metal clips into place or buttons snaps. For a long while, I used a simple 10″ long traditional mallet made from nylon.

I wanted something more compact and…of course, custom made for my workflow. I really enjoy using my Copperhead mallet, so much that I wanted a bigger, soft head version for strike leather punches. I call it the Death Rattle…you’ll know why soon enough.

Let’s go!

Step 1: Cutting the UMHW Stock

First, let’s cut the stock for hammer striking head. Some 2.5″ diameter Ultra High Molecular Weight Polyethylene will do the trick, no silly nylon or HDPE, this stuff is the bee's knees in terms of weight and durability. A healthy 3.5″ was cut off from the log. This stuff was tough, even with my most aggressive wood saw, it took quite a lot of work to make it cut.

I bought mine from a plastics supplier off eBay. You CAN use nylon or HDPE, I just wanted UMHW.

Step 2: Facing the Edges

Now time for the real work…the piece was chucked up on the lathe. It JUST fit on the mini lathe. This is the most dangerous step, with the uneven surface of the saw cut face, it could catch the tool and bounce right out of the jaws. I wanted to face the end so as to flip is over to get a better grip on the material.

My lathe only has a 7" capacity so the this is pretty much the max when it comes to large stock.

I used my metal lathe, but if you have a wood turning lathe, that'll work just the same.

Step 3: Drilling and Tapping for the Handle.

I managed to buy a bunch of tool handles from Lee Valley tools for a scant price of $.50 each. They came all ready to go with a 5/16 fine thread rod. I eyeball the depth for the hole depth and the threads. UMHW is tough, but it yields to sharp (key, SHARP) tools easily.

I used a center drill to get a good spot for the bigger drill bit to hog out the hole.

If you are in a hurry, you can stop here, the hammer is done...but let's keep on going..let's make it awesome.

Step 4: Tenoning, Cleaning and Flipping.

I then turn a tenon on the so the handle has something visual to sit on. I also face the outside edge, this isn’t needed but it’s nice to have a fresh face to start off with. I don’t show it, but the work was supported by a live center point on the tail stock.

The UMHW came quite dirty and a bit scared from transport, but since this is going to be wailing on leather punches and other tooling, it wasn't critical for the surface to be glass smooth. Still, I like nice things, so I surfaced the face with a light cut to reveal some fresh polymer.

Step 5: Hollowing the Head

This was the hardest part of the operation. The plan is to hollow out the mallet, fill it with steel shot and plug it. I use a 1.25″ Forstner bit to hog out the inner material about 2″ deep.

See how the tenon makes the handle look like it belongs there instead of just attached.

Step 6: Plugging the Hole.

Time to make the plug. I made a small mistake and used the 1.25″ Forstner bit instead of the 1″, but I found a fix that worked out well. That is a ring of 1″ ID, 1.25″ OD schedule 40 PVC pipe. It’s a near perfect fit and will need to be pressed into place.

Once I had the spacer, I cut off and machined a bit of 1″ nylon rod to use a s plug. The fit was a tiny bit loose, so I wound two wraps of electrical tape onto the nylon lug and hammered/pressed it into place. To avoid separation, a 1/32 hole was drilled and counter sunk with a 1/16 bit a small nail was driven into place.

Chucked the plug with pvc sleeve into the lath again and faced it so it was one unit, then pressed it into the hammer head. The same hole set and nail was driven in to pin it place. The fit was pretty tight to begin with, but this is just for added security.

Step 7: Filling the Void With Steel Shot

The tapped hole that accepts the handle is now clean through to the hollow void in the head.

My reasoning and theory behind this, and I haven't seen anyone else do this, is to have a deadblow type carvers mallet. The loose .177 bbs inside the head of the mallet would transfer all it's energy to the object being hammered and not blow back.

Since it weighs MORE than my other hammer but much shorter, I get much more control of what I am hammer to have a more precise and effective blow.

Once I was satisfied with the weight, I quickly threw it back on the lathe and made a deep chamfer on the bottom portion of the mallet so If I wanted to choke up on it, I could. This shape is a classic carver's mallet shape so I know it'll work well.

Step 8: Stop, Hammer Time!

Alright, done!

I've been using this hammer for nearly a year now and it's still as fresh as you see it in the photos. The weight and balance is excellent and the striking force vs energy investment on the swing is well worth the effort of making this.

The only mod I've made to it is adding some 1mm self adhesive cork to the plugged (top) end of the mallet so when I put it down on the table, it would sit without shifting around.

Thanks for reading and hope you get out to making your own Death Rattle!