Tech specs for diamond drill bits
glass drill bits and core bits.

Diamond Drill Bits | Glass Drill Bits

Frequently Asked Questions:

Diamond Drill Bits

Technical Specifications:

Which bits should I use to drill glass?

You should drill small (less than 1/2") holes in glass using a diamond drill bit with a round end. Either a ball shaped or a round end cylinder. Either will do fine. The rounded end is the part that actually drills the hole in the glass. For holes larger than 1/2" use a diamond core bit.

Please use plenty of lubrication during drilling. Remember that you are "grinding" a hole though the glass. Diamond drill bits (even coarse) will leave a much smoother finish than spade bits or twist drills. Diamond drill bits will not cause the chipping that is common with spade bits and twist drills.

Diamond drill bits with a medium or coarse grit are a good choice for drilling and shaping glass. The constant rotation of the bits tends to smooth any rough edges on the glass even with the coarse grit.

The finish may be smooth enough that it won't need any additional finishing. However, each application or project is unique.

Lighten the pressure even more as you approach the back side of the glass. Once you have drilled halfway through the glass, an even better solution is to flip the glass over and drill a matching hole from the other side.

This means the thin piece of glass just before the breakthrough (the part easiest to break) is in the middle of your glass and not at the front or back surface. You won't chip the front or back as the drill bit finishes the hole.

Ready to look at drill bits for glass? Click here for Glass Drill Bits

Do you need a hole larger than 1/4"? Read just a little more.

Diamond core bits are used to drill holes 1/8" and larger. Diamond core bits drill "the circle of the hole" that you need, leaving a "glass plug" in the center. Once you have drilled completely through the glass then the "glass plug" simply falls out. Choose a diamond core bit with a head diameter the size of the hole that you need. We carry diamond core bits up to 4".

Diamond core bits can be used with hand drills but it is hard to hold them steady. Diamond core bits work much better using a drill press.

Does this sound like what you need? To see diamond core bits from 1/8" to 4" click here.

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Which bits will fit my Dremel® tool?

Any diamond drill bit with a 1/16", 3/32" or 1/8" shank will fit in your Dremel® tool. Dremel® tools have an adjustable chuck or they have interchangable collets. If your Dremel® tool has an adjustable chuck simply open the chuck far enough for the bit to slide in. Then tighten the chuck until the bit is held securely in place.

If your Dremel® tool has interchangeble collets, you will need to have a collet that is the same size as the shank of the bits you are ordering. Bits with a 1/8" shank require a 1/*' collet, etc. Collets are size specific. For example, 1/8" collets will not hold a smaller bit securely and larger bits will not fit into a smaller collet. All Dremel tools come with a 1/8" collet. If you have more than one collet then you probably already have both 1/16" and 3/32" collets.

Click here to see diamond drill bits for your Dremel® tool.

Need a 1/16" or 3/32" collet? Click here to see: 1/16" & 3/32" collets.

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Why are your prices so much lower?

We purchase these diamond bits from a "name brand" manufacturer. We buy them without their name brand and are able to pass these savings along to you.

The bits on the 1/16" shank are the diamond dental burs used by dentists in chairside operations. The bits with the 3/32" shanks are used by dental labs to make dental appliances such as crowns, bridges and dentures. The larger bits are made by the same manufacturer for industrial use.

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Are these bits any good?

Yes! The smaller FG (1/16" shank) and HP (3/32" shank) bits are made by a US manufacturer for use in dentists' offices, dental labs, medical labs, hospitals and industry. The larger bits are used in the aircraft industry and by machine shops worldwide.

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Are they guaranteed?

Yes! We unconditionally guarantee these burs to be free from defects in materials or workmanship. If you are dissatisfied with their performance for any reason, please return them for replacment or a full refund. They are covered by a 100% quality guarantee.

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What's your return policy?

If you are dissatisfied with your bits for any reason, we will gladly replace any bit(s) or refund your money. Your choice. No question's asked.

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What are my shipping options?

The best shipping option is FREE. Most of our customers choose "FREE First Class Mail". However, we also offer UPS Ground, 2nd Day Air or Overnight Shipping as additional options at a moderate cost. International orders are shipped International Global Priority Mail or by UPS Worldwide Express. If you have specific shipping requirements such as FedEx, DHL, or want to have the shipping charged to your own shipping account, please contact us by email or by telephone. We will do whatever we can to accomodate you. Please note that shipping times for USPS options are obtained from the USPS website. UPS cost and delivery times are provided directly from UPS.

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Which credit cards do you accept?

For your convenience we accept Visa®, MasterCard®, American Express® and DiscoverCard®. You also have the option of printing your order form and mailing it with a check or money order.

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Is giving my credit card information over the internet safe?

Our store is hosted by Yahoo Stores. All order information including credit card information is encrypted for your protection. For additional protection, credit card numbers are automatically deleted from the servers 30 days after you place your order.

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Is there a minimum order amount?

Yes, to keep our order fulfillment costs down and our prices low there is a $25.00 minimum order amount.

My Question Wasn't Answered.

If your question is not addressed in our FAQ section please email our general manager, Guy Reddick.

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Are these bits stainless steel?

Yes, these bits are machined from Series 300 stainless steel. This is sometimes referred to as "surgical quality" stainless steel because it is commonly used for medical and dental instruments.

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Are they concentic?

Concentricity is a measure of their "roundness" or how close they are to a perfect circle. Bits that are "out of round" will wobble at high speeds.This is extremely important for bits designed to be used in high speed handpieces.

To ensure concentricity the head and shank are machined as a single piece on computer controlled swiss screw machines from Series 300 stainless steel. The heads are not welded or brazed to the shank. By machining the entire bit from a single piece of steel the bits are never "out of round". They will not vibrate or wobble at high speeds. The 1/16" shank bits are used in air powered dental handpieces which turn as fast as 450,000 revolutions per minute. The 3/32" shank bits are used in dental laboratories. The larger bits are made by the same company and are used in the aircraft and electronics industries.

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What type of diamonds do you use?

Our manufacturer uses a proprietary blend of natural and synthetic diamonds. This mixture ensures that you get the best possible combination fast cutting and longer life. The diamonds themselves are purchased from two different diamond companies. The natural diamonds are mined by DeBeers® and the synthetic diamonds are made by GE Superabrasives®.

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How close are the tolerances?

A tricky question. You want absolute concentricty in the shank and head but you also need a rough to semi-rough diamond coating for better cutting. The blanks are machined on computer controlled swiss screw machines to be within 0.0005" of their blueprint specification. Then they are diamond coated for faster, smoother cutting.

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What is the diamond coverage?

These diamond drill bits are double-layered not single-layered for maximum diamond coverage. The diamond coating process is a proprietary process that maximizes the diamond coverage and ensures a secure bond. The diamond coverage exceeds 100%, meaning that the diamond coating overlaps itself in places.

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How are the diamonds bonded?

The diamond coating is applied using a electroplating process and utilizes a proprietary masking process for maximum coverage, a secure bond and clean shanks. The diamonds are electro-bonded to the stainless steel blank using a nickel alloy matrix bond.

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Are these sintered bits?

Sintered diamond bits depend on the head being worn away to expose the next layer of diamonds underneath. Sintered diamond drill bits work well for granite, concrete and rock. They cause excessive blowout on the back of glass. The bits we recommend for glass use a proprietary nickel bonding method. The bits we recommend for granite, concrete and rock are sintered.

I need more information..

If you need additional information or if your question was not addressed in our Tech Specs section please email our general manager, Guy Reddick.

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Drill Glass LLC
1227 Rockbridge Rd.
Suite 208-164
Stone Mountain, GA 30087


Office Hours: (Monday-Friday) 8:00AM to 4:00PM EST

All orders received by 3:00PM (EST) are shipped the same business day.

Thank you for your business. Please send questions, comments, and suggestions: Guy Reddick by email.

Thanks again!