# Proper bit for a 1" diameter pocket?



## DavidGiles (Dec 12, 2012)

First post here, so I might as well start off with a dumb question.  I need to create a simple pocket as shown in the attachment, and I'm not sure what bit to use. It needs to be a 1" diameter circular pocket with a depth of 1/2" and with a reasonably clean/flat bottom.

Could I just use a basic 1" diameter plunge cutting bit, like an Amana 45236, and plunge straight down to the depth I need? Seems to me like it would work, but would I end up with a conical projection on the floor that matches the central indention in the end of the bit? I assume bits like this one are intended to move along a channel (dado) which automatically cleans the bottom as the bit moves, but will it clean the bottom if it doesn't move in any direction except up/down? If not, is there a bit with a flat bottom that WILL give me a perfectly flat bottom in the hole?

Thanks!

David


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## jschaben (Jun 21, 2009)

DavidGiles said:


> First post here, so I might as well start off with a dumb question.  I need to create a simple pocket as shown in the attachment, and I'm not sure what bit to use. It needs to be a 1" diameter circular pocket with a depth of 1/2" and with a reasonably clean/flat bottom.
> 
> Could I just use a basic 1" diameter plunge cutting bit, like an Amana 45236, and plunge straight down to the depth I need? Seems to me like it would work, but would I end up with a conical projection on the floor that matches the central indention in the end of the bit? I assume bits like this one are intended to move along a channel (dado) which automatically cleans the bottom as the bit moves, but will it clean the bottom if it doesn't move in any direction except up/down? If not, is there a bit with a flat bottom that WILL give me a perfectly flat bottom in the hole?
> 
> ...


Hi David - I like Amana bits but they have a bad habit of billing some of their bits as "plunging" when, in fact, they will only effectively plunge in a "ramping" operation, that is, while moving the router. MLCS does have true plunging straight bits which feature an extra cutting blade across the bottom of the bit. Amana has some similar but they are called "super plunge" bits. Here's a link to the MLCS bits:

MLCS Plunge Cutting Straight Router Bits

I suspect you would burn the bit you referenced up before you made the 1/2" depth of cut because of the heat generated at the center. Another issue with that bit is the 1/4" shank which, in addition to the heavy stress on a small shank, also reduces the heat sinking capability of the bit.


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## harrysin (Jan 15, 2007)

John is spot on with his answer.


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## jw2170 (Jan 24, 2008)

Welcome, David.

Also, there is no dumb question. But sometimes ,not yours, we get amusing ones......

The collective force is here to help you.


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## JCJCJC (May 15, 2012)

I've had good experience with bits like this from George Hsu on Ebay. He used to do a similar bit with a longer shank, it might be worth asking him about it. However, going by the dimensions given there, with the router bottomed-out and reaching an inch into the hole, you'll still have 7/8" to grip in the collet which ought to be enough.


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## AndyL (Jun 3, 2011)

Hi David, you could also consider drilling the holes with a Forstner bit.


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## JCJCJC (May 15, 2012)

AndyL said:


> Hi David, you could also consider drilling the holes with a Forstner bit.


No Andy, he wants a perfectly flat bottom. A forstner will leave an indentation in the middle, won't it? Well, mine do!


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## DavidGiles (Dec 12, 2012)

Thanks for the welcome and for the great advice guys! :thank_you2:

That MLCS Plunge Bit sounds like it should do the job quite nicely. I did say I wanted a perfectly flat bottom, but actually a small central indention at the bottom wouldn't be a problem (just didn't want any *protrusions *at the bottom), so the Forstner bit should be okay as well.

But I do want exceptionally clean edges of the circle on the surface of the board, so will the plunge bit (in a router) or the Forstner bit (in a drill press) be better in that regard? FYI, the boards being used are Melamine with MDF substrate.

Thanks again!!

David


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## rwbaker (Feb 25, 2010)

Good Morning Andy, Had the same problem about a year ago and I used a drill press and a 1" 4 flute end mill. The fostner is a better solution if the bottom does not have to be perfectly flat or if something is going to rotate on the flat use a fostner and a 1" piece of HDPE (milk carton) to reduce the friction and provide a flat surface.

Good Luck - Baker


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## DavidGiles (Dec 12, 2012)

Thanks Baker! Yeah I wondered if an end mill might be a good choice (for example, #01720648 at mscdirect). But out of curiosity, why do you say that a Forstner bit is a "better solution"? Does it make a cleaner cut at the surface with sharper edges at the entry point?


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## Bradleytavares (Feb 25, 2012)

How about a Forsner drill bit in a drill press? These are designed for this purpose.


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## grbrico (Feb 16, 2012)

I used a bottom cutting 1/2" end mill to do the holes for a marble game I made for my sons.


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## richtink (Dec 5, 2012)

If you have enough scrap of that material, maybe you could try a few methods and let us know which works best. If it is a one shot deal, then I would use the forstner, as it has worked for me before when making pockets for hidden hinges.


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## DavidGiles (Dec 12, 2012)

Bradleytavares said:


> How about a Forsner drill bit in a drill press? These are designed for this purpose.





Bradleytavares said:


> How about a Forsner drill bit in a drill press? These are designed for this purpose.


After doing some research on Forstner bits, I came across the "Colt Maxicut" bits. Sounds like they should do a really nice job! They're a bit expensive, but this is for a production job and the $30 price isn't a deal breaker.

David


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## DavidGiles (Dec 12, 2012)

richtink said:


> If you have enough scrap of that material, maybe you could try a few methods and let us know which works best. If it is a one shot deal, then I would use the forstner, as it has worked for me before when making pockets for hidden hinges.


Thanks Rich! I do have plenty of scrap for testing, but I just don't want to spend a fortune on a wide variety of different bits trying to figure out the one we need to use.  It sounds like the Colt Maxicut forstner bit will be the first one I try. I'm betting it'll do a good job, but if not then we'll try the MLCS Plunge Bit mentioned before.

Either way, I'll let you know how it goes.

David


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## Ben I (May 21, 2010)

I agree with Andy, a forester bit in a drill press will do the job nicely. Buying a forester bit is much less expense that an end mill. 

To ensure a very clean cut: Make sure the bit is plumb and doesn't wobble. Clamp your work piece down and slowly introduce the bit to the surface of the wood. withdraw the bit occasionally to clear out the wood shavings from the bit. The get the correct depth use a piece of masking tape around the outside of the bit at the desired depth.

Regards
Ben


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## JOAT (Apr 9, 2010)

jw2170 said:


> Also, there is no dumb question.


James, sounds like you have never been an NCO in the military. Believe me, there are PLENTY of dumb questions.


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## jw2170 (Jan 24, 2008)

*NCO...Non Caring Official.....*



JOAT said:


> James, sounds like you have never been an NCO in the military. Believe me, there are PLENTY of dumb questions.


No, I have ever only been a 'grunt' or a seaman.

I do however remember some questions I SHOULD have asked.....


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## DavidGiles (Dec 12, 2012)

Ben in Cypress Texas said:


> I agree with Andy, a forester bit in a drill press will do the job nicely. Buying a forester bit is much less expense that an end mill.
> 
> To ensure a very clean cut: Make sure the bit is plumb and doesn't wobble. Clamp your work piece down and slowly introduce the bit to the surface of the wood. withdraw the bit occasionally to clear out the wood shavings from the bit. The get the correct depth use a piece of masking tape around the outside of the bit at the desired depth.
> 
> ...


Thanks for the extra tips on getting a clean cut Ben! We'll probably use a depth stop on the drill press to control depth. And I've ordered one of those fancy schmancy Colt Maxicut forstner bits so hopefully it, along with your tips, will give me the quality I'm looking for.

David


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## rwbaker (Feb 25, 2010)

DavidGiles said:


> Thanks Baker! Yeah I wondered if an end mill might be a good choice (for example, #01720648 at mscdirect). But out of curiosity, why do you say that a Forstner bit is a "better solution"? Does it make a cleaner cut at the surface with sharper edges at the entry point?


Forstner is less expensive and most people do not have a 1" Jacobs chuck - I work 50/50 in wood and metal so I have the equipment. Another good place to obtain end mills and brad point (another option) bits is W T Tool Co.

again good luck,

Baker


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## MikeMa (Jul 27, 2006)

I believe as well that a forstner bit on a drill press is better suited for this task. For a flat bottom, here is one thought that would work. Buy a second bit, and grind off the pilot. Use the first bit that has the pilot to start the hole, then finish the hole with the second bit.


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## DavidGiles (Dec 12, 2012)

Just wanted to report back. Got the Colt Maxicut forstner bit and tried it. The hole does have a small indention at the bottom in the middle, but that isn't a problem for our application, since we're putting a flat bottom object in the hole and it will just sit over the indention (an upward protrusion *would* have been a problem because it would have interfered with the flat-bottom object).

Anyway, the bit does a BEAUTIFUL job! At least when brand new.... Now I just hope it'll do 1,000 cuts this nice. 

David


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## richtink (Dec 5, 2012)

Anyway, the bit does a BEAUTIFUL job! At least when brand new.... Now I just hope it'll do 1,000 cuts this nice. 

David[/QUOTE]
Thanks for the feedback David. Good luck with the 1000 cuts, don't overheat it and it should do the job.


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## DavidGiles (Dec 12, 2012)

richtink said:


> Thanks for the feedback David. Good luck with the 1000 cuts, don't overheat it and it should do the job.


Thanks Rich!

David


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