Making a hammer eye drift ~ Brian Brazeal

[Alec.S]

I am posting this on behalf of Brian Brazeal.
I am sure he will later post a description of these photos
how to make a drift for hammer eyes.



Alec / Brian

[brianbrazealblacksmith]

Thanks, Alec.
This is for Phil Krankowski-pkrankow's thread, "Taper calculation/ hammer eye drift".
Phil, the above picture is in response to you're inquiry on making a combination hammer eye punch/drift.
Starting out, before having a handled punch for punching handled tools, a combination punch/drift is a good solution. The long vertical piece in the picture is an example of that.

But, the first tool I would make with that would be a handled punch like the two shown beside the combo drift/punch. Then make drifts.

All the above started out as one inch round 5160, because that Is what I have on hand at the moment. 5160 happens to be what I prefer for this application, also, but I have and will use 1045 and 4140 if that is what I have at the moment. I usually use 1 1/8" and 1 1/4" round for larger hammers. Since I'm mostly making top tools and the occasional farriers hammer, one inch is all I need.

The diameter of stock you choose will determine the maximum size of your hammer eye.

I don't use standard measurements unless someone were to order these things from me in quantity, and that does not happen. So I use what I have. I get drops, so I devide them up into pieces. For the drifts, I need ten to twelve inches, for the handled punches, I need three to three and a half inches. I use the heat from my coal forge to determine how much material I will start with. I take a full heat, witch is about six inches, and I will start my forging about an inch into that heat. So I'm only grabbing about 4 1/2 to 5 inches to draw the taper.

I do not own a power hammer, so I rely on a hand hammer. These drifts are the time that I'll use the full thow of my hammer for an extended period of time. If you cannot relax, free up your shoulder, and let your hammer do the work, you may not want to attempt these with a hand hammer.

The best technique for drawing these by hand is half-hammer faced blows over the far edge of the anvil.
Drawing out hexagonal tapers is also much more efficient when you want to end up round than square, octagon to round.

The size that you finish with is dependent upon the size of eyes you want to make. For larger holes I start with the larger stock and finish the round taper proud of 1/2 inch, for smaller holes 3/8 inch.

[ironsmith]

Thanks for the Explanation of the taper Brian. This helps a lot and I intend on trying it out some time soon!

[pkrankow]

Thank you Brian and Alec

Your explanation is very clear Brian.

Phil

[alexhhisc]

That is the HT procedure for drift/punch?

[pkrankow]

No. Heat treat was not discussed in this thread. I start by looking up material specifications for the material I am using, then develop the heat treat schedule I wish to employ. The schedule recommended in the specifications is what I aim to use, but my kit may not allow certain procedures.

Some of these tools may be used "as forged" without any special treatment due to their size, specifically the drift.

The handled punch should be heat treat for best results. The struck end should be left soft or "as forged" and the business end hardened and tempered per the material used.

The combination punch I probably will leave "as forged" since I need it to punch very few holes before being replaced with a more suitable tool, the handled punch.

Phil

[brianbrazealblacksmith]

I do not heat treat either one. The drift and punch would both loose their temper performing their functions.

[pkrankow]

I do not heat treat either one. The drift and punch would both loose their temper performing their functions.

Well, that would certainly take a few steps out of the operation. If I had some hot-hard metals I might consider arguing the point some, but I see your logic for more common materials on this one, and the materials I have available to me at this time.

Phil

[brianbrazealblacksmith]

Phil, I'd like to hear some arguments on why and when to heat treat. I used to heat treat most all my tools a long time ago, but now I only heat treat the tools I use for cold work like hammers, anvil like tools, and punches and chisels that I use to layout cold and do small work with. I am usually only doing hand work or working with a striker, so I use forgeable steels like 4140, 5160, and 10 series to make tools with. I make, use, and maintain my tools, and I do not want nor need the high alloy steels for any of the work I do, and I work larger stock by hand than anyone in the world that I have seen. Now, if I had power hammers and presses to work with, I would definitely employ some of the high alloys especially for punching, but correct me if I am wrong, wouldn't these also lose their temper while being driven deep into the material and heating up to red?

[Alec.S]

super steels are for women and children....
sorry, couldnt resist!

[pkrankow]

I did a quick look up on 1045, 4140, and 5160. They temper to a broad range of levels.

I am surprised because they all retain improved hardness up to about 1200F. This is visibly dull red in a shadow box. I am having a hard time finding numbers comparing annealed to tempered at various temperatures however. This information is regarding material that is tested at room temperature. At the deeper draw the parts are more "spring-like" in that they can tolerate a larger amount of elastic deformation without cracking. Presumably they will also tend to plastically bend instead of breaking with a higher draw temperature.

I have found NO information about how these materials retain the hardness at the elevated temperature, but this is only several minutes of Google-fu. The information I have found indicates that these materials are better used cool.

Phil

This information is when the material is returned to room temperature.

1045 will be about Rockwell 30C after going to 1000F from hardened. Fully annealed it is about Rockwell 5C ( converted from Rockwell 85B), normalized about R 13C - R 19 C (Brinell 167-229)

4140 annealed is R 13C, hardened and tempered to 1000F is R 37C

5160 annealed is R 13 C, hardened and tempered to 100F is R 37C

Data from
http://www.matweb.com/index.aspx

[pkrankow]

Based on some articles I found on boiler materials 700F seems the upper limit of what a "simple" steel can tolerate without being subject to creep deformation (in a boiler application). The material was A106 in one article, but I did not catch the grade of it.

That would be about the middle of "steel gray" for a tempering color.

Do your tools tend to remain below that temperature? It would seem that they may benefit from a full heat treat if they do, but then if the service life without a full heat treat is suitably long it would not make a difference in the first place.

The last point is you are getting an acceptable service life from tools left "as forged" and real-life experience is a very strong argument.

Phil

[Alec.S]

brian is getting more than acceptable service from his left as forged tools . His punches for example, ( maybe not for him but for me ) can get red when they are punching and get stuck, so then you have to wait untill there is no visible colour then cool it off in oil, but when you are deep down in 2 inch yellow hot steel, even with the time for one hit, yes, it gets as hot as a grey temper. The trick is to hit once, take it out, hit once take it out etc. and after every 5 or six blows, cool it off in oil.
Brian, please correct me if i am wrong in any of this.

[Francis Trez Cole]

Well Alec you are right. The heat transfer from a 2" piece of steel to the drift or punch is fast making annealing null and void. it is best to get as hard as you can and punch away it is not like a tool used to texture metal. The tools that you use made out of steel the needs to be quenched in oil take much longer to cool. I use 3 punches and 3 drifts for the process. I have see drifts start to deform then have to reform and harden again and back to work. once you start and have a piece of 2" steel hot the last thing you want to do is loose your heat.

[thingmaker3]

Based on some articles I found on boiler materials 700F seems the upper limit of what a "simple" steel can tolerate without being subject to creep deformation (in a boiler application). The material was A106 in one article, but I did not catch the grade of it.

Creep occurs at constant high temperature. Punches or chisels subjected to brief heats would not be susceptable to creep. ;)

[pkrankow]

Creep occurs at constant high temperature. Punches or chisels subjected to brief heats would not be susceptable to creep.

Yea they are subject to outright deformation to being hit, bent and otherwise abused. Makes creep deformation look like nothing.

If when properly used, getting the tool out immediately, the tool still gets above a temperature that a low load causes deformation, I think any treatments to improve the durability while cold make little difference. The first hit is what matters, when the worked metal is as soft as possible, and the tool is as hard as practical.

Phil

[clinton]

The tools are not annealed if they are used as forged- and the forging process changes grain structure. When you compare the manufacturer's specs with a forged tool its like apples and oranges

[monty]

i have a bent spike from the front of a jcb loadall, from the bend to tip it is probably 2 ft, it has roughly the same taper(square taper) how much should i cut off for a drift like that?

[brianbrazealblacksmith]

I'd have to have that where I could see it to make that choice.
The thing you are after with a hammer eye drift is the size of holes you are planning on making, and the length you are comfortable with.

[monty]

here are some pics of the bar and the hole size intended, the hammer is the larger of the two i made with alec.

[Tom Allyn]

Looks like that piece is up to full size at about 11" and starts to curve at 12". I'd probably cut it off at 12" and then rework it as necessary.

[monty]

from the point it starts to curve at 21"

[monty]

the hammer eye is 1" long, sorry for the bad picture

[Francis Trez Cole]

SKMBT_C22011051009020.pdf
I put this together for members of FABA after Brian came to my shop and did a hammer making Demo it has come in handy for my friends who attended the demo as they set out making hammers Brian is inspiring and if you can learn his hammer method your whole style and the amount of work you can get done will double

[Wesley Chambers]

Would like to see how some H13 would perform in these forms, I have seen and used H13 for fullers on horseshoes, and they tend to spend a good deal of time in contact with hot steel when working on a draft shoe.