Dremel 664DR Diamond Drill FlipBit

Ok I read the instructions. Had water on the ready! Went slow! Did not force the bit! And oh it went through beautifully but the instant it went through It (the bit) broke!!!! It’s easy to use. Cuts great but it’s a waste of money to pay that much for one bit to break that easy!!! I just wanted to revise my review due to the kindness and support I received from The Robert Bosch Tool Corporation. I called and explained what happened and Andy M was very helpful and understanding concerning my problem. He promptly addressed the situation and mailed me out not only one replacement but 2. Now that’s what I call AWESOME Customer support. Something more companies should take advice from. Thank you Andy M !!! You’re the BEST!

Unfortunately I dropped my dremel one night and snapped tip off , so I needed another. These aren't always in-stock in big box store. This is name brand and the quality you would expect when you use it properly just don't drop it like I did. LOL. You can see in second picture what I use these for. I went ahead and bought 2 so I wouldn't be without. I really do like that I have a thin more precision side and a thicker side that cuts through faster

I do not recommend for drilling agate. Bit will dull quickly or break even under water. Never use dry for drilling stone. Works well for materials of 7 or less on mohs hardness scale.

Seems good. It works both ways.

Useful for drilling stone for jewelry making. I put the stone in water on a piece of wood and have a nice hole in no time. I would recommend.

Looove this bit. Perfect for drilling seaglass! I just wish the bit would last longer as each end only gets through 10 pieces at most.

Broke on 3rd use. Didn't drill well either. It didnt appear to be any stronger than a regular bit. Waste of money.

Perfect diamond drill bit for my glass pieces.

Have drilled through rocks and sea glass, still going strong. Needs to drill under water to preserve the tip and it will serve you well

Does what it's supposed to do.

Llegó a tiempo, si sirve para su propósito, buen precio (solo lo he usado una ves pero funcionó excelente)

At first I was so pleased. Thought it was great. Love the small sized hole in my glass. Then the bit snapped off. Consulted with Dremel, and made sure I was doing everything right. Got another bit and it broke on hole 6 or 7, but no worries, I had bought a back up. Broke in 4. Using the other side (larger size) is disappointing too. My black glass snowman hats defeat these bits. Boring 1/3 way through in 3 minutes?… On to the next bit… no better. So not worth what I paid. Would be lovely if I could consistently drill holes in my 3 mm pieces of glass.

I tried to drill a small hole into a quartz stone and the drill bit snapped as soon as it touched the stone. I have a lot of dremel products and have never had a problem. Very disappointing.