Tapping a hole in a metal part can often remove the need for a nut. Rather than passing the bolt through the metal part and putting a nut on the back side, you can sometimes tap the threads right into the metal part and simply tighten down the fastener. Tapping metal creates threads in the metal. You can then put a threaded fastener into these threads.

To create proper threads in metal, you need to drill the correct size hole in the metal. To determine the correct size hole to drill into the metal, you will need to reference a drill and tap chart such as the one at this link:

DRILLING AND TAPPING CHART

Basic Tapping Instructions

Locate the size of the fastener you need to install in the metal. Identify the thread size and pitch on the drill and tap chart. (The fastener size is generally displayed on the left-hand side of the chart.)

Place the piece of metal on a stable work surface. Keep in mind that a properly secured work piece is a safe work piece.  When drilling and tapping, pieces can spin, move or even rise up on the tooling causing damage or worse – personal injury!

Select the “drill bit” from the set that matches the size recommended on the chart we have provided. Secure the tooling in the drill motor and put on your safety glasses and other safety equipment.

Drill the hole into or through the metal, depending on the type of metal and the application. Liberally apply cutting and tapping fluid to the “drill bit” while you drill to lubricate and cool the drill bit. Remember that slower RPM rates are better than faster ones.  Too fast and you will damage the “drill bit” or maybe even your part.

Select the tap from the tap set that matches the size of the fastener you will be installing into the metal and secure the tap in the tee-handle tap wrench.

Coat the tap with cutting and tapping fluid. Place a bit of fluid on / in the hole to be tapped. Align the tap with the drilled hole in the metal. Start threading the hole in the metal by turning the tee-handle tap wrench clockwise for a right-hand threaded hole or counter-clockwise for a left-hand threaded hole. Make sure that the tap is straight with the hole to ensure that your fastener will seat correctly.

Reverse the direction you are turning the tee-handle tap wrench if and when you feel the resistance from the tap increase. This will break the shavings and chips coming from the metal. This makes the process of threading the metal easier.

IMPORTANT: Make sure to keep any and all pressure on the tap to a minimum. you only want to press down when starting the tap.  From that point forward, you want to make sure you are only turning the tap and not leaning it from side to side or pressing down.  Some taps are hard and brittle to cut difficult metals. This means that they will snap very easily – especially smaller diameter taps.

The smaller the t-handle tap holder, the better.  Using a larger one causes broken taps often.  As long as you can comfortably turn the tap, you are good.  Look for flexing or twisting in the tap while you go.  If this happens, add more fluid, reverse the rotation for a turn or two to remove chips and continue down.

Remove the tap from the metal, wipe the cutting and tapping fluid from the surface of the metal and turn the threaded fastener into the newly threaded hole in the metal to ensure that the threads are cut correctly.

If the threaded fastener will not thread into the hole, look for debris or metal shavings in the hole and clean them out. It is almost never necessary to re-cut the threads unless your tap is the wrong size or extremely damaged.

Please CONTACT US to discuss your application and receive prompt product cost, literature and technical help.

Drilling through stainless steel is much like drilling through any other type of metal but with a few key differences.

Using high-speed drill bits or better is mandatory. There are also other steps to drilling this material that will make the process easier. Many people have drilled holes into plain old steel with satisfactory results. Although drilling through stainless steel is different from drilling mild steel, the basic technique is much the same. Here’s how to get those holes drilled without ruining “drill bits”

Things You’ll Need

1. Variable speed power drill
2. Gloves
3. Eye protection

Basic Instructions

Hold it secure! Clamping the part down is critical.  If it is not properly clamped down, you may see it move, spin, or even lift up causing damage or even injury while drilling.

“X” marks the spot. Locate the exact spot where you want the hole and mark it with a permanent marker or even use a center punch to mark the location. Use heavy-duty tape to mask the area around your mark if you are worried about the chips scratching the surface as they spin. The best way, by far is to use the center punch to make a sharp depression in the metal. Holding the punch firmly on your mark, rap it sharply with your hammer once or twice to set the tiny puncture. Make sure it does not move between the hammer blows. This will prevent the drill bit from sliding away from your target as you drill.

DO NOT DRILL YET, but if the hole is larger than 3/8″ diameter or 8mm, use a two-bit process. Unless you have a drill press, hand drilling in metal is most easily done with a two-step process when you go above those sizes. To begin, install a “drill bit” roughly half the size of the hole diameter you need. For example, if you need a 1/2″ hole, start with a 1/4″ inch bit. Once you have drilled the 1/4″ hole, install your 1/2″ bit and drill again to finish the job. Thinner metal, for example less than 1/8-inch thick, may allow the use of a single bit to accomplish the task but has a much higher risk of “grabbing” as the tool breaks through the material.  The “drill bit” turns into a screw-like device.

Put several drops of lubricating oil into the depression you made with the center punch. With your gloves and eye protection on and hearing protection in place, hold your drill perpendicular to the bracket, insert the tip of the bit into the punched hole and begin to drill.

Slowly pull the trigger until the bit gains rotational speed being careful to keep it on target. Ultimately, the drill bit will win the contest and you’ll have bored that hole. Switch bits and begin again if needed to finish off the final hole.  Add more lubrication often.  Stainless does not conduct hear well so the tip of the “drill bit” will get very hot, very quickly.

Clean it up. Once you’ve drilled the hole, wipe off the excess lubricating oil with a rag. As you do, you’ll notice that the back of the bracket is fairly rough. Using a metal file, take down the ragged edges of the hole being careful not to damage the bracket. If necessary, apply more heavy-duty tape to mask the area.

BONUS TIP: By using an even larger drill bit, you can de-burr the hole on both sides if desired.

Consider using some sort of plastic or felt on your clamp if the surface will be easily damaged.

Drill slowly and allow the bit to do the work. Some will tell you that if you apply too much pressure, friction will cause your drill bit to redden with heat which will ruin it or your piece of stainless steel. If you are spinning slow enough and have enough lubrication, then this will not happen. In fact, more pressure can sometimes cause the drill to stay cooler as it travels through virgin metal below the last cut surface on every rotation.  Let off on the pressure as you break through to avoid spiraling into the hole.

Overheating the tool can happen if you engage the drill to its full speed. The trick here is to find a happy medium, that “sweet spot” at which the drill, the bit and the metal cooperate fully. If it appears there’s too much smoke from the lubrication, back off immediately. Allow the bracket to cool for a few minutes and start the process again. You’ll save the “drill bit” in the process. When in doubt, drill slower.  Also, the larger the hole diameter, the slower you should spin the “drill bit” to reduce heat.

Once you’ve removed shards and burrs, you can sometimes finish smoothing the area with steel wool as long as the marks left by the process are desirable.

Eye protection is a must as are gloves! Work safe!!!

Don’t touch the bracket or the drill bit with your bare hand until they have cooled. Changing bits during the drilling operation should be done with gloves.

Please CONTACT US to discuss your application and receive prompt product cost, literature and technical help.

Drilling metal typically is not too difficult if you set up properly to do so.

Some would call it a very tricky operation. With a few precautions, you too can be an expert at drilling metal items.

The first thing to consider is, “What is it that I actually want to accomplish?” Drilling metal requires the right tooling – often simply called a “drill bit”, proper hole and location measurements and a good amount of patience during the set-up process. Do it right the first time because there’s always time to do it right the second time, eh?

Things we suggest you always have handy (and use!) might be:

• Safety Glasses
• A Hand Drill, Drill Press, Bridgeport or Similar Mill, etc.
• Tooling or “Drill Bits”
• Cutting or Drilling Coolant / Fluid
• Information – See the following CHART for some idea of the speed you should be running (RPM) when using HSS (High Speed Steel) tooling

Basic Drilling Guidelines or Instructions

1. Always secure the piece that you want to drill. Use a proper vise or a clamp so it can not slip, spin, lift up, etc. If you are using a simple hand drill, you will need both of your hands to keep the drill steady.
2. Measure exactly where you need to drill and mark it so you can see it. Bonus Tip: Our favorite method for marking a hole is to use a punch or something similar. This allows the “drill bit” to find the location more easily.
3. If you need to find the center point on a part, measure your length and mark the half way point on all four sides of the piece. Draw a straight line across the center from top to bottom and then do the same from side to side. Your center point is where the two lines intersect. See our tip in step #2 for marking the center point.
4. If drilling by hand, hold the drill steady and drill slowly. It is very important that the drill not slip. If the drill slips, you can cause damage, drill in the wrong location or even injure yourself or others.
5. With a hard to drill metal like stainless steel, you need to make sure there is plenty of coolant. Drilling at the proper RPM rate or even slower is a necessity. Bonus Tip: Pushing relatively hard once the drill has started into the work piece can sometimes be helpful. It causes the “drill bit” to cut a larger and deeper chip which keeps the cutting surface of the tool in cool material rather than right at the surface where heat was generated on the previous rotation. Typically, this is useful on automated machinery and not as important when hand drilling.
6. Generally, slower RPM rates mean better results when time is not an issue. If your cycle time is critical, then work with a tooling supplier to determine the optimal speed and feed rate for your actual material and tooling. We often suggest test drilling on a drill press or milling machine to help determine this prior to purchasing a self feed production drilling machine.
7. Choose the right drill bit for the job. If there is any question about whether it is the correct tooling, you should contact a professional tool dealer or machinist who can help you.
8. A cone “drill bit”, step “drill bit” or graduated style tool is sometimes useful for soft metal projects. It is designed to cut various sized holes in thin sheet metals typically but can be used on some other products with success. Typically, these tools are not professional grade though so special order tooling may be necessary if this is part of your plan.The transition or cone can be smooth or it can have graduated steps on it. Sometimes you can use one of these to cut a whole range of sizes of holes. Simply drill to the diameter you wish and save the time and cost of switching out tooling. AutoDrill Production drills can be adjusted to repeat the same depth of drilling to an accuracy of 0.001″ to 0.003″ on average and are easily adjusted by the end user to lock in this depth for maximum efficiency and repeatability.Bonus Tip: If you lack horsepower on your machine and you can’t use a cone or step drill to manage the drilling load, start with a smaller size tool. Gradually increase the size until you get the dimension you are looking for.Bonus Tip:When using a multiple drill spindle head, you can often stagger the tooling lengths to minimize the horsepower requirements. AutoDrill even manufactures custom gang drill / multi-drill heads with different length spindles if necessary.
9. Get better tooling for more difficult jobs and harder materials. High-speed steel (HSS) drill bits are often coated with a special aluminum nitride layer and are good for most metals. Avoid using them without coolant and proper speed and feed rates on aluminum as the metal debris or chips tend to become stuck or “welded” to the tooling. This can often make clean hole drilling impossible. It can increase the burr on the top or bottom of a part, create an over sized hole, create poor hole quality, etc.There are cheap imitations out there. If you need a real tool, we suggest going to a tooling distributor rather than a local hardware store, etc. Here are two massive online sources for tooling: McMaster-Carr and MSC Direct (…There are others, but this will get you started in the right direction.)
10. There are higher quality tools made such as Cobalt, TiN, Carbide or even Diamond. Keep in mind that some tooling simply is not made for smaller drilling machines. Micro vibrations caused by a lighter weight machine (i.e. not 10,000 lbs for example!) can cause the most expensive and durable tooling in the world to prematurely dull because the vibrations destroy the cutting edge.
11. Take your time to do the job safely and cleanly. If you do not use caution when drilling metals, you may end up with holes that are out of round, and there is no fixing that problem. As we have said before, there may not be time to do it right the first time according to the pressures and deadlines… But there always seems to be time to do it right the second time. Just do it right the first time, every time!
12. Bonus Tip: When working in the shop, chaos is your enemy. Act like a surgeon. When you take a tool out and use it, replace it immediately after finishing the job. Many people have been injured and many jobs have been ruined because someone thought they could clean up at the end of the day or at the end of the job.
13. Beware of metal bits, chips and curls flying or spinning around. Always wear safety glasses and any other safety equipment when drilling metals.
14. If you are the one setting up a manually triggered production drill, consider ordering a Two Hand Anti-TieDown (THAD) start button assembly. This forces the end user to press two buttons at the same exact time in order to start the drill. This can help eliminate injuries in your shop or in your customer’s shop! Do you really want your customer filing a lawsuit against you for not properly protecting their employee? It may not be right, but the legal system unfortunately allows them to do it so prepare now.

Please CONTACT US to discuss your application and receive prompt product cost, literature and technical help.

Important Note: This write up covers only the very basic details concerning the subject. Please contact us for more detailed information, especially if it concerns your production, or other high volume drilling needs.

Metal drill tooling, often called “drill bits” are the most common you will encounter when searching for drilling tools – we will just call them drill bits from here forward since that seems to be the acceptable term for most.

The design of a drill bit for metal drilling depends on various factors such as:

• The material you need to drill a hole in
• The volume of drilled holes
• The speed in which you must drill the hole
• How deep the hole is or how thick the material is
• What direction you will be drilling in (horizontal, vertical, some combination of both, etc.)
• The finish you want to create, such as a screw head either exposed or hidden beneath the surface

Choosing the right drill bit becomes easy once you are experienced at drilling a wide range of materials. We hope that this basic write-up will help you to set up a very efficient and profitable scenario for your business.

Instructions:

Check that the drill bit is the proper type for the job. AutoDrill suggests talking to your tooling supplier to choose the right drill bit type. Here are some very basic guidelines…

1. Standard steel drill bits are good for most simple drilling jobs such as most plastics, most woods, aluminum, brass, bronze, cast iron, etc.
   HSS or High Speed Steel drill bits are good for some of the more difficult applications where you are drilling structural steel, slightly hardened steel, stainless steel, etc.
2. Cobalt, TiN coated or even carbide or diamond drill bits are sometimes needed for materials such as tool steel, stainless steel, stone or ceramics, or even woods such as ipe that have silica nodules within the material, etc.
3. High helix drills can be useful when drilling deep holes where removal of the chips or debris can be difficult.
4. Reduced tip or pilot drills are useful when drilling into surfaces that are rounded or when you need the drill to stay “on target” better. This also helps when you have less than adequate horse power on your drilling machine.
5. Split point drill bits are useful for rounded surfaces, drilling at a slight angle, etc. They start much more easily than a standard web tip drill and lower the thrust required to start and maintain a drilling process.
6. End mill-type drills are used when you can not use a drill bit with a tapered tip.
7. A spur-point bit is useful for most jobs around the home, its design ensuring a straight hole.
8. A tile bit, as the name suggests, is best for drilling ceramics.
9. A flat wood bit creates a large hole, but requires a powerful drill.
10. Masonry bits are suitable for drilling through stone.

Pick a size of drill bit. This obviously depends on your job and desired hole size when you are done. Drill bits are still measured in fractions of an inch for most of the USA although metric sized tooling has become much more common. Typically, they come in 1/32″ increments although tooling can be acquired in 0.001″ increments or smaller when necessary. The four most common drill size options are:

1. Fractional (Generally starting at 1/64″)
2. Metric (Generally starting at 1mm)
3. Number drills (1 to 60 typically but others do exist)
4. Letter drills (A to Z)

Select the design of drill bit that will work best for your specific application. We strongly suggest speaking to a tooling expert if this choice is difficult to make or the application is critical.

If drilling into wood or any material where a common fastener will be used, decide if you want the fastener head exposed above the surface of the material. If you want it recessed or hidden (on a wooden cabinet, for example) select a step drill bit or one with a countersink or counter bore attachment / provision. The drill bit widens the hole at the end so the fastener’s head is hidden below the surface a bit.

BONUS SUGGESTION #1: If you are looking to drill a very large number of holes in a manufacturing or production drilling environment, we suggest you experiment with different drill bits from different suppliers during your initial set-up process. Determine which create the highest quality hole, last the longest, throw the chips or curl best for your fixture, provide optimal drilling stability, etc. Using the right drill bit for the right material is always important.

BONUS SUGGESTION #2: If you are about to purchase a production drilling machine for an application, keep in mind that they are often highly efficient versions of manual drilling machines. You can often test your process on a drill press or a Bridgeport type milling machine before spending your hard earned cash on a selffeeder unit.

Please CONTACT US to discuss your application and receive prompt product cost, literature and technical help.