Punch, Chisel, Drift,... combined?

[rockstar.esq]

I'm a novice with very little time or tools. I've been trying to forge small tomahawks out of a scrap digging bar. My intention is to end up with handle similar to a pickaxe where the handle enters the top of the head and doesn't require any wedges etc. So far I've been able to punch one head which I later tried to drift to the correct profile. This took me most of a day and I wasn't really happy with the results. I think my drift was entirely too cone shaped and it needed to be smaller in circumference.

For my second try, I started by using a chisel to start, figuring I could drift the hole faster. I also made a smaller drift which had less taper to it. While it took me half as long, my drift failed to utilize the entire slot cut by the chisel. The handle hole is shaped like a tear drop with a line extending lengthwise on either end.

At the end of the day I decided to try and use one large piece of bar stock I had on hand to make a new tool. I've shaped it exactly like a tomahawk handle, and it tapers to a chisel point. My thought is that I can use one tool to cut, drift, and finish the handle hole. I've never seen anyone else using such a tool which leads me to suspect my inexperience is keeping me from seeing some missing detail.

The whole reason I thought to make the tool was to ensure that I didn't have to worry about tool sizes being incompatible like my current chisel and drift. The bar stock is from the same digging bar which I believe is medium carbon.

Why drifts aren't made with cutting / punching faces on them?

[John B]

Drifts are what they say, a tool to drift out a slot or hole to a finished size.

If you reduce the width of your chisel, then the drift should produce a finished eye

Basically you are just opening up the chisel slit at the moment and because the slit is too long you are leaving the split ends in.

Because you are making a tapered form, You may have to slit , drift and then introduce a tapered drift to give the finished size/shape you require, you may also need to support the workpiece with a bolster plate.

Others may have different ideas on how to do this.

Persevere and you will get there.

[petere76]

Rock star,

Walk before you run, go with the basics. Slit then drift . Slitting chilsels have a very uniform shape. Learn the shape, it does not change.

The forumals for the length of the slit vs the finished hole are easy to read up on. The drift tooling has the final hole crosssection and shape along with the expansion factor incorporated into its dimensison.

Do "your" homework and read up just a tad so you understand the relationship between the tooling you make and use vs the end result you want. Its important, and once the concept is grasped it will save you a lot of time and make for a better end result. Some research is required and remember to take notes so you have your own journal (notes) to reference.

Example, round hole, mild steel = dia (finished) + 40%. Square or rectangular hole = perimiter total x .40. Round hole =round drift . Square hole = square drift. Both have a tapered start and a short tapered finish.


Good luck,
Peter

[brian.pierson]

Rock Star,


Take a look at these two topics:





Both should help answer questions. You can also search for other slitting articles or ones on tomahawks.

good luck

Brian P

[Frosty]

Slit and drift is my 2 bits too. Check out Brian Brazeal's slitter and drifts. I've never seen a slitter work as well as his design.

Having a drift really makes refining the eye much easier and yields a much better results, not to mention conformity in all your products.

Let us know how the pick eye works for a hawk please.

Frosty the Lucky.

[Fosterob]

If your slot punch (chisel) is to long for your drift you can heat the area where your hole is and upset it to shorten your slot. That should also give you a little bit more material on each side. That will alow you to play with different length of slots without making multiple tools.
Rob

[Nakedanvil - Grant Sarver]

Not unusual to have that tear-drop shape in the ends. I don't care how hard you drive the drift, if you want to get rid of that completely you gotta drive the drift in tight and hammer from the end and keep tightening the drift. If that is the goal, it's better to punch than to slit.

[rockstar.esq]

Thank you all for your replies, I have a few questions.

I thought a slitter offsets material but the slitters in Brian Brazeal's posts appear to be creating a slug. Does this mean his slitters work through both upsetting and punching?

I understand that the slitter I used was oversized for the drift which is why the slit extends beyond the drifted hole. Wouldn't a drift that tapers to a slitter solve this problem?

Is there a reason that this is done in two operations, slit/punch then drift?

I'm curious because a drift is a very specific purpose tool which would lead me to think they're nearly always custom made. Is there a reason that it's not appealing to make a combination slitter and drift?

Petere, Are you saying that a drift has to be 40% smaller than the intended dimensions of the hole? All of the books I've read have failed to provide anything like the detail in your post. I really appreciate you taking the time to explain it to me.

Frosty / Grant, my drift is teardrop shaped in cross section and tapered lengthwise similar to a pickaxe. I'm trying to make it similar to this: http://www.coldsteelknivesdirect.com/riflemans-hawk

Rob, I'm not sure I have the skill to upset the material on the sides only. But since it's already messed up I can certainly use it to practice!

Again, thank you all for your replies.

[Nakedanvil - Grant Sarver]

Two things: To combine everything in one tool would make it rather long, the slitter needs to be rather slim, so the whole thing would end up a foot long or so. A long drift is OK. Sometimes we want to use the same slitter for many different kinds of finished holes. Seems like the slitter would be hard to control if it had the drift on top or it.

[rockstar.esq]

Grant, The tool I made is just about a foot long so you're spot on! I find shorter tools hard to told with the heat of the blank so close to my hand. Plus being longer, I can sight it better to keep it straight up and down. I see your point that making a combination tool makes it useful for only one thing whereas if I made two tools, I'd have greater range of utility.

Thanks!

[Fosterob]

Rob, I'm not sure I have the skill to upset the material on the sides only. But since it's already messed up I can certainly use it to practice!

Easy, after slitting your slot re-heat the bar around the hole , stand it on end and hit it until your slot is the length you want.
Rob

[bigfootnampa]

Well I have seen pics where Brian has done this so it is doable. I think it's not the kind of solution you are seeking though. Yes Brian's typical way is to use a slot punch rather than a traditional slitting chisel... it works even better though in most ways. I have also watched smiths cutting slits with a shorter chisel and moving it back and forth as they cut to get the length of slit that they desire. Usually at least a two man crew for this though as you have tongs and chisel to control besides the hammer... I think it would be hard with a hold down, whereas with a full width tool (slot punch or slitting chisel) you can somewhat control the blank with the tool after the cut is started.

[rockstar.esq]

Once again, thank you all for your help!

[jake pogrebinsky]

Rockstar,you're right in that the longer the tool,the better your aim and the control of it,in keeping it straight,among other factors.
BUT,the drawback is that if that one tool is longer than all else that you use,then it'd also take a special anvil(height-wise).Else,you'll hurt your arm,or look foolish balancing on top of a bucket(my proprietary technique).

(I'll just insert some spotty thoughts here,too lazy to systematise them...).

The reason that the slitter or a chisel are different tools from a drift is that they're usually something decent around med-C,and the drift is a big old chunk of crap mild(easier to come across as well as to shape).

Peter is very correct,the proportions such as the one between the slitter and the corresponding to it drift are quantifiable,and charted.The two tools really are a set,one set of them for each size/shape opening.

Upsetting the slitted stock is easy,and is actually a necessary part of the making of some types of mortices,in joinery of iron.What helps in that is to close the slit back up,somewhat,getting the sides of it straight and parallel to each other,and to the direction in which you're banging on them .The extent to which one does it,in many instances,is to where the slit becomes a round hole.At that stage the material displaced out of the sides during slitting is upset back into them,making each 50% of the parent stock,or slightly more(as some will again be lost in drifting.However,you need not do it to that extent,for your specific purpose.).

What CAN cause the un-drifted(and/or undriftable)ends of the slit is,among other factors,your Temperature Range.The sides of the split will move(forge,elongate)easier than the drift can be forced into the ends of the split.Remember,the sides are what you're "pushing" against,it is they that provide the resistance necessary.

The many solutions to all this are listed above,each of the previous posts covering one or more of them.I'll add the one that hasn't been mentioned yet:

The front of an axe eye(end closest to the blade)carries NO mechanical load.It's shape is superfluous.
For that reason many makers,old and current,have chose to let all the difficult to avoid fudge to go there.
Also,it's difficult to get to,as the blade is attached to it .
For that reason you'll see many tomahawks with very poor to indifferent fit at the front of eye,and on many old(and some modern)wrapped construction axes the crack of the beginning of the weld there is left in place,and ignored.It contributes or subtracts nothing of the physics of the striking tool.
So,one chooses the (vastly)more important end of an eye,the back,or the poll end,for a good fit to the haft.
To insure it,simply pound on it as you're drifting,as per Grant's advise,and you'll be in God's pocket.

Best of luck.Make a bunch of axes!Good on you for attempting the compression fit of the haft,it's got a lot going for it!(One VERY good smith i know uses this type of eye on all his hammers,a couple of different sizes cover all his striking tools.It makes all his handles interchangable,easier'n ... to replace,and very conveniently removable for dressing faces/edges/et c.And all it takes is one set of slitter/drift for each size,and you're in business.WELL worth the R&D,so don't be discouraged ).