Drill Rod

[Tim Winters]

I am new to metalworking and am uncertain on which type of drill rod to buy for general projects. Several project plans I have require specific diameters of drill rod.
When I placed my first order for drill rod I was asked if I needed Air, Water or Oil hardening type. On their recomendation I ordered Oil hardening type.
None of the project plans I have seen yet require hardening, the drill rod is just used as is. Could somebody advise me here? What type of rod is generally used?
Thank You, Tim

[bobtoy]

I'm not too much more knowledgable than you, but I believe I have read somewhere that water hardening is desirable, even if you do not plan to harden it. It is as cheap or cheaper than the other forms. I have not had any problems using it in situations similar to your application.

[huntfamgjc]

Tim
some plans i have seen and herd of call for drill blanks ,If that is what the plan calls for it is not the same as drill rod! Blanks are pre ground to exact size and prehardened so you would just cut leanth and true the ends.
George

[Bobby Roakes]

Hi
Drill rod comes as you say air hardening(A) water herdening (W) and oil hardening (O) the easiest to work with is the water hardening This is also the easist to harden in a home shop. as it is done with water. The next would be the Air with as it says is hardened by bring it up to temp for a period of time then down the a tempering temp. This is done best in a heat tret oven. A series is the most stable. Oil harden is the hardest to work with. You can harden it at home but you run the risk of fire.
The above is true for flat stock also. you can tell what you are getting by the first letter. A,W,O. I hope this helped you have a good day.

[SGW]

The oil hardening warps less when hardening (in theory, at least). Unless you need the qualities of O-1, get the W-1, it's cheaper and for nearly all home shop stuff works just as well.

But unless you are going to harden it, look into getting something that machines better than drill rod. Get some 1215 or something like that. If you want really easy machining, get "Ledloy" (12L14, I think), but I've found that Ledloy and other leaded steels tend to rust amazingly easily, so I avoid them.

Personally, I like 1145, sold under the brand name "Stressproof" or "Fatigueproof." It machines to a beautiful finish and is strong.

[Richard Brown]

<font face="Verdana, Arial" size="2">Originally posted by Tim Winters:
I am new to metalworking and am uncertain on which type of drill rod to buy for general projects. Several project plans I have require specific diameters of drill rod.
When I placed my first order for drill rod I was asked if I needed Air, Water or Oil hardening type. On their recomendation I ordered Oil hardening type.
None of the project plans I have seen yet require hardening, the drill rod is just used as is. Could somebody advise me here? What type of rod is generally used?
Thank You, Tim</font>

Are you really interested in "drill rod" or simply looking for bar stock for doing general machining work? Unless you are making cutting tools or have a specific requirement for high strength or wear resistance, you may only need a mild grade of steel, brass, aluminum, etc. If such be the case try 12L14 steel. Though a bit more expensive than other alloys, it cuts like butter and takes on a very good finish.

[Ron LaDow]

Just a comment on leaded steels.
If the part will need welding, forego the finish and machinablity of leaded steel. Maybe somebody can weld that stuff, but I can't.

[bobtoy]

I like what I heard about 1215,"Ledloy", 1145, "Stressproof" or "Fatigueproof."

What is a good source ?

[MikeHenry]

McMaster-Carr (www.mcmaster.com) sells 12L14 I think. Metal mart (www.metalmart.com) is a good source for small quantities of many metals that hsm'ers need and they have some pretty decent technical info on their web site. They sell by the inch, so you don't need to buy a 20 foot length when you only need 2 inches, but their per pound price is a lot higher than the big buys if you want to buy in quantity.

[SGW]

You can try a steel supplier in your area. You'll have to buy 12' pieces, probably, but you'll also find that a 12' piece, in the smaller diameters, is not all that expensive. You may be able to buy less than a full length, but the cutting charge to do so may be more than it would cost to buy the whole thing. In larger diameters it may pay to buy less; in smaller diameters, probably not.

They may have a minimum order, which may or may not be a problem depending on how much it is.

I think Brownell's sells short legnths of Fatigueproof in small diameters, but the selection is limited, or was the last time I checked. Still, it would be a way to try it out. You will find that you can't hurry the cutting, but it does cut well.

There are mailorder places that sell small quantity, but it can get expensive and they may not have the types you want. Do a web search.

[SGW]

See also http://www.execpc.com/~metal/

[JimmyK]

Hi Tim:

One of drill rod's claims to fame is that it is a "tool steel". Tool steels are dimensionally pretty stable. That means they creep or crawl very little due to the stresses created by heat treating. Other steels, like chromoly (4140, etc.) do "move" noticably with heat treating.

Regarding whether to use oil or water hardening drill rod: I prefer to use water hardening because of the flames and vaporized oil generated by quenching in oil.

It's a really great show to watch the first time or two, but it gets old pretty quick if you do much oil quenching.

The third issue about drill rod vs. other steels is in handling. Drill rod is usually sold in 3 foot lengths. Easy to store and handle. Other steels come in 10 to 12 foot joints.


____________________________________
Jimmy K. Ramirez / Kingsville, Texas
jimmyk@gcol.net

[jix]

The original question addressed projects that called for drill rod. If hardening is not required by the project author, then the only reason for using drill rod is that it is dimensionally accurate off the shelf. All the other steels that have been offered in the replies will have to be machined to dimension. I have found that, if hardening is called for, air hardening steel is easier to work with, is dimensionally the most stable, and costs more.And, in many cases, needs no tempering. When building tools, careful tempering is needed. But if you're looking for wearing qualities, tempering is superfluous. And air hardened parts don't crack.

[SGW]

Well, "dimensionally accurate" to a point. Drill rod has a dimension tolerance too, sometimes as much as a thousandth, nearly always at least half a thousandth, and sometimes that is too much error. Other steel is probably within two or three thousandths, and sometimes that is close enough. It all depends on what you're building.

[artificer in metal]

try buying turned and ground bar. its usually - 0.0005 (in diameters under 1.5")but check on that we use it for precision shafting

[Frank B. McClain]

One thing to remember about leaded steel do not use for high stress parts. Gun barrels come to mind. If you need high strength don't use leaded steels. Good turning. Frank

[AJE]

Another thing about drill rod. Its often centreless ground, which means that while it has a constant diameter it may not be circular in cross section.

[rdulas]

Before we jump too far off the track, my understanding is: the definition of "circular" means the thing MUST have a "constant diameter". I will agree that the drill rod could have sections where the center axes are not co-axial. But I wager that most HSMs will never see the potential problem mentioned above.

Rick