# Why can't I find straight concrete drill bits?



## Mr Chips (Mar 23, 2008)

The reason the bit from the box of anchors probably worked best is because it's a rotary bit, not a hammer drill bit

the problem is probably not the bits but that you are hammering into cinderblock. Get a rotary masonry bit, and use in rotation only.


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## DawsonMobley (Dec 8, 2010)

The bits are bent before I ever use them them the first time. Here's a quick vid of the unused Skill brand 1/4 inch bit I just bought tonight after returning the Bosch brand 1/4 inch bit, that actually wobbled worse.



I don't know if this is the norm for concrete bits or If I'm just incredibly unlucky?

That much wobble makes it extremely difficult to get the hole started on my mark and it makes the hole too big so my anchors just want to spin when I try to put a screw into them.


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## Bud Cline (Mar 12, 2006)

You are using a hammer drill and drilling into concrete block and you are complaining about a 1/32" deformity? Are you kidding?


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## DawsonMobley (Dec 8, 2010)

Bud Cline said:


> You are using a hammer drill and drilling into concrete block and you are complaining about a 1/32" deformity? Are you kidding?


No, i'm not kidding, that was the least bent bit I have found, most of them have been 1/8th inch of wobble or more as in the video above and that enlarges the hole enough that my anchors fit too loose and makes it nearly impossible to get the hole started on my mark.

Do you think it's acceptable for a brand new unused drill bit to wobble that much at the tip?


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## Bud Cline (Mar 12, 2006)

I don't suppose anyone should expect to start a perfect hole exactly on mark in a cinder block to begin with.

If you'll watch your own video you'll see that the drill bit is perfectly straight when the RPMs are maxed. What's wrong with that?

Use a center punch and hammer to chip out a small starter hole. Then max-out the drill and place it in the starter hole. Once you have a hole started push on the machine to fully engage the hammer (if you think you need a hammer).

Drill bits come in different sizes you know and so do the anchors.

Write your congressman and tell him to keep allowing companies to import Chinese goods and inside of five more years China will have all the jobs and the U.S. will have 75% unemployment.


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## PaliBob (Jun 11, 2008)

Dawson, Don't blame the Bit, blame the *'chuck'*.
.


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## DawsonMobley (Dec 8, 2010)

PaliBob said:


> Dawson, Don't blame the Bit, blame the *'chuck'*.
> .


it's not the chuck, my regular drill bits spin perfectly true in it and the wobbly bits are just as wobbly in my other two drills as well.


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## DawsonMobley (Dec 8, 2010)

Bud Cline said:


> I don't suppose anyone should expect to start a perfect hole exactly on mark in a cinder block to begin with.
> 
> If you'll watch your own video you'll see that the drill bit is perfectly straight when the RPMs are maxed. What's wrong with that?
> 
> ...


Good tip on using a punch to start the hole, I hadn't thought about trying that.

On your other point though, the bit doesn't straighten out with rpm, the rpm's simply hide how bent it is. When something out of true spins fast enough (rather it's a wheel or a bit) the eye loses the ability to perceive the out of round condition. 
You can easily see the center point of the bit move nearly 1/8 inch up and down at slow speed and that doesn't change at higher speed, just your ability to perceive it changes.


Any way, I'm done arguing about it since no one here seems to think a drill bit should be straight for some reason

Thanks for the input.


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## DangerMouse (Jul 17, 2008)

All of MY bits are straight..... 

perhaps the ones you bought are "Made in *you know where*" crap?
Most of the BB stores sell them....

DM


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## DawsonMobley (Dec 8, 2010)

DangerMouse said:


> All of MY bits are straight.....
> 
> perhaps the ones you bought are "Made in *you know where*" crap?
> Most of the BB stores sell them....
> ...


What brand are your bits?


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## DangerMouse (Jul 17, 2008)

All different, I'm sure, I've had them for many years.
As old as they are though, I'd wager all Made in USA.
I'd go look, but they're out in the tool shed and it's cold out there! lol

DM


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## piste (Oct 7, 2009)

DawsonMobley said:


> I'm getting extremely frustrated. I have bought four different brands of masonry bits for my hammer drill in 1/4 and 3/16 sizes in the last few days and every one of them has been bent to some degree towards the cutting end of the bit. I search online but find no one else complaining of this problem so have I just had extraordinarily bad luck or what?
> I am putting up shelving on cinder block walls and the anchors need a certain size hole to work properly. The wobbly ended bits just wallow out the hole so big the anchor spins when I put a screw in it. I even tried some Bosch hammer drill bits and two of the three I bought were bent worse than some of the cheaper brands I tried. Ironicly the cheap 1/4 inch bit that was included with a box of anchors I bought is the closest to being true that I have gotten my hands on so far but even it is about a 32nd out of true at the tip.
> 
> I'm mainly just venting but if any one can shed some light on why it seems most concrete drill bits are not true right out of the package, I'm all ears


GREAT post. You are not alone. I had the very same experience in recent months and found it very frustrating. I was like...WTF??? I have NO idea why seemingly EVERY manufacturer can make regular wood bits of all sizes that are perfectly true ...yet virtually ALL masonry bits are noticeably bent to the naked eye!! If someone can shed light on that....I'd be very curious.

I've been trying to drill into brick...got some Vermont American which quite ironically given a name like that.... I believe are made in China indeed...and are the very same ones that Sears sells as Craftsman. In my case I'm using a pure rotary drill and that combo hasn't worked very well at all. I have used Tapcon screws in the past and have recently been advised to use THEIR masonry bits...have picked one up but haven't had a chance to try it yet. Also determined that a rotary drill into masonry...at least MY bricks...works very poorly and need to get myself a hammer drill.


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## Mr Chips (Mar 23, 2008)

Haven't used any in a few years, but GALAXY always offered very good, made in USA masonry bits, that fit in a jacobs style chuck ( just make sure you don't hammer with the rotary only bits)

http://galaxydrillbits.com/bit106


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