FAQ

Are Irwin cobalt drill bits coated like the titanium ones? If the cobalt bits are Rockwell hardness 66 - 67 HRc, what hardness is the titanium bits? Once you sharpen a cobalt bit and the gold coating is gone, is it just a regular bit?

Cobalt bits are not coated, they are cobalt steel through and through. At the end of manufacture, a cobalt bit is baked in an oven to turn the surface color of the steel a dull gold color. This is done primarily for easy identification by color. If the gold wears off or is ground off in sharpening on a cobalt bit, it is still solid cobalt steel. The cobalt drill bits are made of M35 cobalt steel which has 5 percent cobalt content. The Rockwell is approximately 65.5 to 67 Rockwell C. Irwin titanium drill bits have a hardness of approximately 64.5 to 65.5 Rockwell C. The titanium coating is much harder at approximately 82 Rockwell C. If you sharpen a cobalt bit it is still as good as a new bit, assuming it was sharpened correctly. If you sharpen a titanium bit its performance will drop because the coating is gone on the tip; however, you still have the benefit of the titanium coating in the flute of the bit and on the sides of the bit. It will still perform better than a standard bit.

How do I resharpen Irwin auger bits?

First never sharpen the outside edges of the bit that cut--the spur and side lip. There are three edges you may have to sharpen--the spur, cutter and side lip. Your bit may not have a spur. The spur is a thin piece of metal that sticks up parallel with the screw point above the cutter. To sharpen it hold the bit by the shank or twist against a work bench. Using a flat file, sharpen on the front (as you view the cutting edge) and top inside edge of the spur. Never sharpen the outside. To sharpen the cutter and side lip, hold the bit upside down with the screw point sticking into a piece of wood. This gives you a clear view and access to the underside of the cutter and inside of the side lip. Using a small triangular or square file, sharpen the underside of the cutter and inside the side lip.

How do I resharpen Speedbor flat bits?

Use a small file to sharpen the top of the cutting edge and inside the spurs and on the side of the point. Try to follow the same angles that were ground on the bit when it was new. When sharpening the top of the cutters, make as many strokes on one side as on the other even if you don't think it's necessary. This keeps the cutting edges balanced.

What is the recommended bit speed for flat bits? I am sure that the speed varies by bit diameter and wood species

They have a recommended turning speed of 1500 - 2000 RPM on the IRWIN Speedbor wood boring bits, never exceed 2500 RPM. A good rule of thumb to follow on any drilling tool is the larger the bit the slower the speed. I'd recommend the 1/4" at a max 2000 RPM and slow the speed gradually as you move up to the 1-1/2" size.

What is the function of the hole in an auger bit?

The hole in the flute of the Installer Bits is to hook wire through to aid in pulling wire through the drilled hole. This technique is used by many telephone and security wire installers. The hole in the Spade Bits was initially for hanging it on a finish nail in a workshop. It is also used to hook wires to help pull wires through drilled holes. Some people think the holes are for heat dissipation in keeping the bits cool but it is not.

How do you sharpen your 1" speedbor ship auger bit ?

You should use a small triangular file. Your local hardware store may even stock a Nicholson Auger Bit file. Using the file to sharpen a ship auger only sharpen under the cutter and on the inside of the side lip.

To identify these two parts hold the auger bit with the screw point pointing up. Rotate the bit until you see the single horizontal cutting edge. Looking at the cutting edge, the side lip is at the left hand edge of the cutting edge jutting down.

You should only sharpen under the cutting edge and on the inside part of the side lip. Now that you have located where to sharpen the easiest way to sharpen those areas is to hold the auger with the screw point pointed down and stuck into the corner of a wooden bench or board. You can lean the bit backwards and sharpen with the file those two areas. Try to maintain the same angles that were ground on from the factory.
I am crosscutting oak veneer plywood on a table saw, and the veneer is chipping on the backside. What type of blade would you recommend to cleanly cut across plywood?

A 10", 80T blade with a reduced feed rate would be your best bet. The IRWIN Marathon #14076 would be a good choice.
What is the difference between a nut setter that has a standard hex design vs. one that has a lobular design?

There are a few key differences between these two types of nutsetters. A nutsetter that has a lobular design drives the fasteners on the sides instead of putting pressure on the corners to turn. This helps maintain the true shape of the fastener reducing corner stripping and damage. Additionally, a nutsetter with a lobular design provides corner clearance where paint build up can occur.

A nutsetter with a standard hex design uses the corners of the fastener to drive. Putting pressure on the corners of the fastener will promote corner stripping.

In summary, each type of nutsetter can drive a fastener, but a nutsetter with a lobular design helps keep the fastener in good shape.
What is the proper way to use the reversible offset dovetail saw? I know it is reversible and it has an offset. What side needs to be offset in relation to the side of the cut?

A very common application for the reversible offset dovetail saw is to cut off the bottom of door trim when putting down flooring such as tile, which is thick. Many people will remove base molding but not the door trim when putting down flooring. You should cut off the bottom of the door trim to slide the tile underneath the trim. The offset handle enables you to put the saw parallel to the floor to cut the trim. When cutting off the trim for tile, users will turn the tile upside down for the proper thickness and so they don't scratch the finished surface then cut the trim. It is reversible in case the door is close to a corner and the trim couldn't be cut. It also makes it easier for left and right hand persons.
I plan on using my hole saw to cut into iron. What RPM should I use for best results?

Trying to cut metal too fast will overheat the material being cut, which 'heat-hardens' the work and causes the cutting blade to work harder and wear out more quickly. To answer your question we would need to know what size hole saw you are using. Every hole size requires different RPM for different types of materials. IRWIN always details the optimum drill RPM on each hole saw the package. Before you use your hole saw to cut iron, please refer to the manufacturer recommended RPM for the appropriate hole size.
I am working during the rainy season, and my chalk lines wash away if I don't spray them with polyurethane. Is there any type of chalk that will withstand bad weather, and eliminate this step?

IRWIN makes permanent chalk in either black or red. Because it won't rub, fade or wash away, black or red chalk is perfect for use on subfloors, concrete, metal, and roofs. There is no need to polyurethane. Just snap a line, and it's set. Red, black and yellow chalks are not removable, so keep them away from finish material.

I just bought a chalk reel and the very first marks were hard to see. What happened?

You need to prepare your new chalk reel. Do so by pulling out the line several feet, and rewinding it. Repeat this step a few times. It will help the line absorb the chalk and produce darker, sharper strikes from the start.

Every time I snap a chalk line, a huge cloud of chalk forms in the air. Why?

Most likely, you are also getting a dull, hard to see line. That’s most likely because the brand of chalk has a lower ratio of color to filler. In order for marking chalk to make a sharp, distinguishable line, there must be a much higher concentration of color. Then, when a chalk line is snapped, more color gets absorbed by the surface, and a truer line can be seen.

I just purchased an IRWIN chalk reel and I'm not sure which color chalk I should use for different applications.

Choosing the appropriate chalk if very important. Blue chalk is considered a non-permanent color. It can many times wash away but on some surfaces, it can be permanent. If used indoors IRWIN always recommends white if possible. All other colors red, orange, green, yellow and black are permanent colors. It is nearly impossible to remove them. Choose your chalk color based upon permanency, a contrast to the surface it's being used on.

I just purchased Irwin straight chalk line and I don't know how to use. It doesn't have any instruction on how to use it. Do I need to pour the chalk into the tool? or do I need to wet the string and put chalk on it?
Do not wet the string. Wetting the string will cause the chalk to cake in the reel and on the string.

Here are some instructions.

First you must fill the chalk reel with chalk.
- Take the cap off the chalk bottle.
- Using scissors or snips cut the tip off the cap.
- Open the slide door on the side of the chalk bottle.
- Pull out approximately 12' of string.
- Insert the cut tip of the chalk bottle into the slide door opening and squeeze the chalk bottle. This should force chalk into the reel. Fill it about 1/2 full.
- Close the slide door and wind in the string. You can then repeat steps 3 and 5 filling the reel with more chalk. Don't fill it completely full. Place the cap back on the chalk bottle.
- Pull a longer length of string then you'll need for the first marking job 6 - 8 times and rewind to coat the string with chalk.
- Assuming you have two marks made to strike a line between place the hook on the edge of the board, or on a nail, or have a friend hold it on the mark.
- You place the reel end of the string on the other mark.
- Pull the string tight, grasp the string and lift it off the surface about 12 inches and release. The string should snap back to the surface and make a straight line of chalk between the two marks.
I have the straight-line chalk real, I borrowed it from a friend, but I don't understand how to make the line "snap"?

The string should be stretched tight over two marks to strike a line between. If you can't put the hook over the end of a board or on a nail you will probably need a friend to hold one end. After stretching the string tight between the two marks grab the string with your free hand, lift it up about 8 inches or so and release. The string should snap back to the surface laying down a straight line of chalk between the two marks.
Are the GrooveLock and ProTouch pliers tested?

Yes, the GrooveLock Pliers go through a series of 12 tests ranging from the Extreme Load test that tests the amount of force which can be applied to the handles to a test that measures the amount of twist the product will withstand.

IRWIN ProTouch" pliers all meet or exceed all applicable ANSI/ASTM (USA) and DIN (Germany) specifications.
What does the 'Bi-Metal' mean when referring to a utility blade?

The bi-metal terminology refers to how the utility blade is constructed. With a bi-metal blade, the edge of the blade is constructed of a high speed steel while the body of the blade is made of spring steel. The two sections are welded together to form a single blade. The advantages of a bi-metal blade is that the hardened edge of the blade stays sharp longer than a standard carbon blade and the spring steel body allows the blade to flex without breaking which is common among carbon body blades.