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How To Drill Hard Steel Video

Drilling steel or metal is harder than drilling wood. If you don't know how to drill steel, you can dull your drill bits quickly. Be sure to use a drill bit designed for steel, such as a cobalt bit. Wood drill bits have a special point that were not work with metal.

Use a little oil on the steel to lubricate and cool the drill bit. Heat will dull the drill bit rapidly. Drilling in steel requires a slower drill speed. Too fast and more heat is generated.

Place a block of wood under the steel workpiece. This will allow the drill bit to go into the wood, instead of dulling the bit on a piece of concrete.

As long as you have the proper sharp bit, a little oil and a variable speed drill, you can drill through steel or sheet metal without damaging the drill bit.


Author's Note:

I received the following tip from John Gibbs of Ontario, Canada. Based on his years of experience as a tool and die maker, John provides this excellent tip.

"Hi, I am a retired 71 year old tool and die maker ... worked at my trade for 53 years.

I recently saw the video on how to drill through steel. It was very good. But if you needed to enlarge that hole, then the larger drill bit will often vibrate and produce a chatter which gives a terrible 5 or 6 sided edge instead of a smooth accurate edge to the hole.

The solution is to simply use a piece of emery cloth. Fold about a 1 X 2 inch piece of emery cloth in half, with the smooth side on the OUTSIDE, to avoid scratching the work piece. Place it over the hole to be enlarged, place the drill bit on the emery cloth over the hole and begin drilling. It will automatically center itself. The emery cloth will let the drill bit through smooth and easy, and produces a beautiful smooth edge without a trace of chatter.

Works every time. This is a tip I learned as an apprentice in England. I hope that you find this interesting. It's one of the best tips I was ever taught. Would make a nice little 2 minute video probably."

DRAWING CREDIT: John Gibbs

DRAWING CREDIT: John Gibbs

 

 

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17 Responses to How To Drill Hard Steel Video

  1. Cobalt is more expensive then a good H.S.S bit. For drilling steel like you did it will do a fine job. If you were going into something like stainless you could opt for cobalt although H.S.S. Bit would also work with the right feed and speed. Always remember not to force the drill bit. Let it do the work while applying light pressure. If you are drilling a large hole you should start out with a smaller bit and then use John Gibbs method to finish up.

  2. Sounds like good advice Tim.....I wonder how many really know this ! Passing his on to my son-in-law and his friend who does a lot of building, etc......will let you know if either of them knew this....
    Well since I know totally nothing about drilling.......I really can't comment except to say, should this come up, I will know it and can express it :)
    But I do want to say that is a GREAT tool bag.....would make a great Christmas present or Birthday present to someone......will pass this info around too......have a great day.....

  3. Hey Tim,
    The tip from Mr Gibbs is one of the best I have seen in a long time. Thanks much for sharing it. I have struggled with this problem many times, and the solution is so simple.
    73

  4. I forget that drilling steel, even lighter duty tin duct work requires a different bit than wood. Keeping a set of cobalt bits just for steel would be a great solution. Thanks for the great tip.

  5. In addition to starting with oil, I have a block of bees wax near my drills, when the bit begins to heat, I dab the warm bit on the wax and some melts to the bit, then I continue drilling. It also lubes/cools the bit.

  6. In the past I haven't had a need to 'enlarge' a hole but will keep the emery cloth tip in mind if the situation arises. Good video!

  7. A few thoughts gained from about 60 years of learning from others:
    1. Drill a small pilot hole if drilling a 3/8" or larger hole in steel. Look at the tip of the larger bit to see how wide the very tip is. Make the pilot hole larger than the tip.
    2. Don't bother with using multiple bits to step up to the larger bit. The tip of the larger bit is not doing any of the cutting. The leading edges on the beveled part of the bit do all the cutting. Your pilot hole is relieving the larger bit's tip from trying to cut through the beginning of the hole. It is also possible to chip the cutting edge of a large bit when it enters too large of a pilot hole. An exception is if your drill or press does not have the power to efficiently get through the metal, drilling a series of larger holes can overcome this lack of power.
    3. Use sharp drill bits or you will be frustrated by not cutting into the metal while the bit starts turning colors, which means it needs to not only be resharpened, but retempered.
    4. If your drill speed is slow, you probably don't need oil or dipping in water to finish the hole, but doing so is easy to do. Fast drill speeds are ok for up to 1/4". Stainless steel is a special issue: drill speed must be much slower because heat builds up quickly and is retained by the metal. This is where lubrication to reduce heat is important and several passes of drilling in thick material is necessary.
    5. The larger bits (1/2" or more), if properly sharpened, will cast off pieces of metal, some of which may be long curled pieces. These can be dangerous if eye protection is not used AND can be dangerous if wearing gloves and a piece of metal is spinning on the bit while grabbing your glove.
    6. Smaller and sometimes larger pieces of metal being drilled in a drill press can be forcefully spun around if the bit gets stuck in the piece being drilled. Use a vise or clamp to prevent this.

  8. Typical spiral, or 'twist', drills tend to GRAB onto very thin materials which can either spin the item being drilled, or violently pull the drill into the item; either of which can become dangerous.

    The 'stepped drill bit." is inexpensive, handy, and can be much safer for thin sheet metal such as found for gutters, siding, heating vents. It is a stacked series of circular shapes resulting in a cone, and has only one or two notches running straight down the full length of the cutter cone.

    PRO:
    1) The straight flute avoids the pulling actions and gives constant torque that only gradually increases as each successive 'step' of the cone enters the material.
    2) Nearly all are a good grade of tool steel which endures much use in cutting typical metals found in DIY jobs. Many also have a golden-colored TiN coating that lessens the need for oil or coolant.
    3) There are numerous variants of step diameters, step depth, tool steel and coating, and prices (such as multi-bit kits), so it pays to shop around and find what fits your personal needs.

    CONS
    1) The cutter edge tip shape may not be suited to harder material, such as steel sheet metal. Thin items will bend if forced. This type of drill works best at enlarging an existing or 'starter' hole. Small diameter twist drills can produce the 'starter' hole, but can easily break or encounter the troubles mentioned earlier. I recommend using a special drill bit known as a 'lathe center drill' or 'lathe countersink bit' to make a 'starter' hole when none previously exists in a thin material.

    2) Step depth needs to exceed material thickness for the desired diameter of hole, so the tool is a special-purpose-purchase rather than universal use.

    3) Diameter selection is limited. A drill with longer depth steps often has fewer diameter choices, while shorter depth steps may have more finer graduations of diameter increments.

    4) ALWAYS be sure what is being drilled and BEHIND the material. The bit length travel fot the step diameter desired may send the tip to a depth which contacts something behind or inside. Be especially careful about electrical, plumbing, or 'punch-through' into items beyond the material.

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