The Stovebolt Site Forums The Shop Area The Tool Chest Best drill bits for steel?

I gotta drill out my steering arm ball studs and am wondering what are the best bits to use for this job. The cheapo set I got from Harbor Freight wont even scratch em hardly. :rolleyes:

Shipwright,

Pretty hard..your choices of drill bit material is sort of limited. Most bits, as I am sure you know, are just High Speed Steel. The new rage is to coat them with TIN or NCTIN or TTDTEGBVD or Cobalt or whatever. This is still a coating over a HSS bit!

If you just won the lottery, you could use solid Carbide. Unless you held the steering arm in a fixture and used a drill press or mill to attack it, you would end up with a broken drill bit.

Isn't the steering ball pressed in and swaged over on the back. Could you grind off the swage and press it back out?

Another option would be to heat the ball red hot with a torch and let it cool. This would anneal it. Then cut it off with a small cutoff wheel and drill through the center of the remaining piece.

These steering components are probably case hardened for wear ability, but they certainly aren't through hardened. They are TOUGH, but not BRITTLE.

A coated drill bit with coolant and a slow speed would probably also do the trick. I will bet there are hints-o-plenty waiting in the wings.

Stuart

I suggest calling a local industrial supplier and ask for a stub length solid carbide straight flute drill. It may seem expensive but will pay for itself in time saved. Local machine shops will be regular users of this type of drill for removing taps or drilling hard materials,etc. A hss bit that doesn't cut and rubs on the pc. can work harden it and make it tougher yet.

Curt B.

A good quality high speed drill will work well in most instances. Try and buy a good brand like Cleveland or Precision Twist, Chicago Latrobe etc. Don't run them too fast if you are drilling something hard, and use cutting oil or coolant to keep it from getting too hot.
Becareful with carbide, if you break one off in a hole, you might have real problem getting it out.
IMHO carbide twist drills work best when used in a machine tool (like a lathe or milling machine).

marc is correct to hard to drill,,use the torch or take o machine shop...

we have a Mill & Mine Supply house in Little Rock, they have the best bits in the world, but be prepared to pay $20+ each. brian

Shipwright - I use harbor freight bits all the time. And I jut did what you are trying to do.

You should know that the balls are hardened and wont drill easily. The must be pressed out leaving a softer already drilled area. The hole is an odd size, I drilled mine out to 5/8 inch just so I had a standard size.

You must press them out. You cannot drill through steel that is as hard as the drill bit. Just grind off the bottom opposit the ball, because that has been peened to mushroom out and hold the stud in place. Once you grind off the smashed area, you can press it out or knock it out with a hammer.

What is left will be a tapered hole you can drill out easily with even the cheapest bits. I agree with the other guys, good bits help. But Harbor Freight will sell a set of silver and demming bits from 5/8 to 1 inch for $20. You can pay $50 for a single 1 inch bit. Unless you are doing percise machining, there is no need for it.

The trick is to know what you are drilling. Even the best bits will just burn up if you try something that hard.

There is a writeup somewhere about this on another site. On the backside where the peening is, there is a small chamfer in the body and the ball stud material is swaged in to fill this out. If this material is removed, I think the depth is something like .010", the ball stud will press out easily.

Thanks for the info guys. I did grind the peening off the backside but still almost fractured my wrist trying to beat the ball stud out. LOL I'm on the last one now. The one on the pitman arm. I am making a tie rod type adjustable drag link and the tie rod ends are smaller than the pitman ball stud. So, I thought if I just cut the ball stud off and drill the correct size hole through the remaining stud, I would not have to use a bushing to resize the hole. I thought a solid carbide drill would cut through the ball stud. I'm gonna try this in the next few days when it warms up a little. Wish me luck.

On the drag link you should be able to drill them out bigger to have them straight. I did mine at 5/8 inch and bought some rod ends from grainger for $10 each. That was the cheapest distributer I could find.

There are a couple of pics at my website that show the rod ends and my upgrades. Maybe that will help you. There is also a description of what I did.

two ways to go about this, the 30 piece-10 buck drill set, that u'll need to replace, but hey for 10 bucks, it should get you through the job and who gives a [censored] when u gotta buy new ones, or drop the money on a good set, that with proper use and a little lubrication, should last you darn near forever

I did option one for the past 2 years or so,then got sick or replacing [censored] and went with the good stuff

Just spent the bucks for 1-2 good drills the right size. You don't have to buy a whole set of expensive ones.

Cobalt and a Drill Doctor,
Scott

For some of the smaller sizes, I may buy a pack 10 or 12 of the same size. For instance, 1/8" is a size that gets used a lot for pop rivets. If I break a drill, I just get another out of the package. Nothing worse than having to stop working to go buy a new drill bit. The smaller sizes are usually cheaper by the pack, compared to individually packaged.

One tip on sharpening drills, if the drill point is sharpened off center, it will probably drill oversize. So, if hole size is critical, you had better take extra care in sharpening the bit.

John