Tomahawk Design and Materials

[AKHunter]

I'd like to try making a specialized tomahawk- you could say design driven by intended use. Hunting and trapping are the intended use, so that means that the bit needs to handle chopping brush, limbs, and cutting firewood- traditionally the role of an axe or hatchet. But I'd like it to be able to handle bone, meat, and hide- hunting tasks like splitting a moose's ribcage, chopping through the spine, and chopping off his hock at the knee. Additionally, I plan to put a 2.5-3" spike on the back for checking ice thickness and to ease the job of landing a canoe or kayak on springtime shelf ice. I'm not sure if I can design that much versatility into a hawk without serious compromises, but I'd like to try. 

My planned construction method is a slit and drifted eye, and a welded bit. For the body of the hawk, I have the options of garage door rod (1" diameter, likely mild steel or the horrid A36-everything-melted-together steel), 1" grade 8 bolt (my research suggests some mystery medium carbon steel), or Honda 4-wheeler axle (3/4" diameter of some sort of very tough rust resistant- but not stainless- metal). I really don't like the idea of forging it out of the wheeler axle- forging the stuff is like petting a porcupine- slow and painful, but I imagine that it would be very tough if I managed to pull it off. The bit would be a piece of 1084 scrap left over from my knife stock or a piece of leaf spring (possibly 5160). The handle will be from seasoned birch, alder, or possibly oak- if I have a piece big enough left.

How large should the eye be- 1.5x.75" ovaled? What temp should I temper it at? If I use the grade 8 bolt, should I attempt to harden the spike at all? Or should I scrap the whole idea and buy a block of steel to forge it from?

Any and all suggestions would be appreciated, I've never tried to make an axe, hatchet, or tomahawk before.  

[Michael Cochran]

Your temper will depend on what steel you use. If it were me I'd be tempted to use the axle to make one and then make another one with the 1" rod you have with the 1084 or 5160 steel bit welded in place. Use the both and see which one I like better/performs better. Then if someone sees it and ask you to make one you'll know which route to go. Keep record of your heat treatment so you can repeat or change it if needed.

[TwistedCustoms]

Look at the Gransfors Bruks flay poll hunters axe for design ideas/inspiration. As for heat treat you would be much better off scrounging a two lb section of water hardening medium c steel like 4140. Old truck axles and rams from hydrolic cylinders are inexpensive sources and are easy to heat treat without specialized equipment. Just my opinion based on the info you provided....

The flay poll is not compatable with the spike design aspect but I think it would be a more useful feature for big game than the spike. The flay poll is great for caping and gives the option of using a mallet or heavy branch for powering the cutting edge through bone and connective tissue. 

[AKHunter]

49 minutes ago, TwistedCustoms said:

Look at the Gransfors Bruks flay poll hunters axe for design ideas/inspiration. As for heat treat you would be much better off scrounging a two lb section of water hardening medium c steel like 4140. Old truck axles and rams from hydrolic cylinders are inexpensive sources and are easy to heat treat without specialized equipment. Just my opinion based on the info you provided....

The flay poll is not compatable with the spike design aspect but I think it would be a more useful feature for big game than the spike. The flay poll is great for caping and gives the option of using a mallet or heavy branch for powering the cutting edge through bone and connective tissue. 

I just looked up the Gransfors axe. It seems like I good idea, but I think I'll pass on the flay pole. Please don't take offense, I'm not disregarding your idea due to preconceived ideas- at least I don't think I am. Here is why I think a spike is a better option for me. I haven't caped, or assisted in caping since my highschool days when I worked for a guide, and I don't plan on doing it ever again. I hunt to put meat on the table, not for sport, and my hunting is in a National Park with subsistence privileges. I know, unthinkable anywhere else, but when you live in a 4 million+ acre park, that's the only place to hunt. Since I'm in the park, I end up with fairly stringent rules on when, where, and how I travel to the hunt. Basically its boat, foot, and if we get enough snow, snowmachine. Weight is at a premium because it usually involves a lot of hiking, and packing it out with 800 pounds of meat. The early winter hunt usually involves early ice that is usually barely thick enough to walk on, but too thick to push a boat through.  

To make a long story short, I've got a good hunting knife for skinning, and I don't want to use the bit of the hawk for safety checking ice before I step onto it. Falling through the ice  in Alaska can be a death sentence for someone who swims well- and I swim like the average rock.

I'm intrigued by your suggestion of 4140. How does it hold an edge? If I go that route, do I follow industry standard HT, or a different regimen for a good edge? I'd love to try 80crv2 or Cru-forge V, but I can't stomach the price for a block of that size.

Any recommendations for total head weight on this project? I'm thinking around 1.5 pounds finished.     

[TwistedCustoms]

The 4140 won't hold an edge as well as 1084 assuming good heat treat on each but the 4140 is easily obtainable in dimensions suitable for piercing/drifting the eye. A small forging in the 1-2 lb range can be water hardened and tempered using hot drifts inserted in the eye till the color runs out to the cutting edge. Easy as pie. If edge retention is the number one factor you could weld in a 1084 bit and do the heat treat for the 1084. I haven't oil hardened 4140 but if the 1084 hardens the 4140 should be tough enough for the body/spike even if it doesn't harden. A little reading will show if the two are compatible for the same range of heat treat. I use 4140 for hammers, hot cuts and hatchets. On hammers and hatchets I like r52-54. Edges hold up well splitting wood and can be dressed with a small file but may not be hard enough for what you want.

Good luck and please share some photos when you get under way. As we say in Ole Miss, "keep your powder dry and happy hunting!"

[Frosty]

A couple points to think about: First, No, we don't have any native woods suitable for axe or hammer handles. While birch may be the hardest native wood it splits too easily and isn't flexible enough so unless it's an emergency it's a non-starter. Alder is another emergency only handle wood, it just won't stand up to the forces involved and Willow is much less applicable. Mtn Ash sounds possible but it's not a close cousin to the bowyer's ash and doesn't stand up.

4140 will take a serious pounding but with only 40pts. of carbon it's a medium carbon steel and won't hold a knife edge like a good axe will. It's not a precision heat treat steel so it's not so bad heat treating by eyeball. A welded bit is a good candidate for a hunting or what I'd call a "bush" axe. Me being me I like 5160 for the bit though 1080 +/- is a good steel if a LITTLE trickier to heat treat. a 1080+/- steel isn't hard to heat treat it just requires a little more precision. I'd recommend you practice on some test coupons first to develop an eye for the right colors. Heck, doing test coupons for any project requiring heat treat using salvaged steel is a good idea.

5160 is a lower carbon steel, mid-high end of medium and contains both chrome and molybdenum for making leaf springs slide without undue wear and the moly to control work hardening. It's pretty forgiving of inconsistencies (little OOps) in heat treat and it'd darned tough in hard use.

For testing ice thickness I much prefer an ice chipper, you need to chop a hole large enough to swing a hatchet if you do it with a hatchet. An ice chipper on the other hand only needs to be a little wider than the handle, say a broom stick. A flat nosed socketed chisel basically. Were I packing it I'd make a "pig tail" screw rather than a socket. The "pig tail" allows you to simply screw it onto a branch or sapling for a handle and not have to pack one along. Of course nobody, even forestry cares if I cut tag alder or scrub willow most places I've been.

You could make a boat hook or whatever you had in mind to help beaching your boat the same way though I just use an oar or paddle and if I need a boat hook on a boat there's a boat hook on the boat.

I understand your desire to not have to pack more than you need to, every ounce counts in the bush, been there done that. Unfortunately a tool that's made to do everything does NOTHING well. Consider this as coming from a guy who's been there and done that.

I've chopped test and fishing holes in lakes with an axe, a hatchet and an ice chipper my vote is the ice chipper, even for a fishing hole. Less weight, no swinging involved and doesn't require a large hole for testing, chip a 2-3"" dia. hole till it breaks through, feel for the bottom of the ice and either grip or note the waterline on the shaft and make your decision. Right?

A small boat can just be run aground gently or poled with an oar or paddle. Just grab the dock or other boat and make fast. We're not talking about a 90' steel hull crabber here.

I believe what you really want and need is a GOOD bush hatchet and I don't see anything about the Gransfors, "flay poll, woodsman's axe" I don't like. I haven't skinned a moose in 25 years and sure wish I'd known about the flay poll. Just because you don't need or want to skin harvested animals doesn't mean not doing so isn't wasteful. We're not talking rabbits and spruce hens here are we?

If you're forging an axe the real important aspect is getting the blade right and the eye straight, the poll is just there you can make it whatever shape and size you want. I don't see it as an issue at all. A flay poll will drive a tent peg if you don't whale on it, and it's just finish grinding. The only issue I can see for a bush axe is the handle and you have reasonably economical access to Kenai don't you?

Frosty The Lucky.