Subject: Re: End Mill 4 flutes vs 2

From: Roger M Weppelman <[email-masked]>
Date: 2 Jul 1996 19:30:58 GMT

>
>Anyone why both two and four flute end mills are available.  Where and
>when and why would I use each?
>
>Thanks,
>John
>

John,

It is a good question. I am no expert but here is the way I see it. Four flute mills 
can cut faster since they bring to bear twice as many cutting surfaces per 
revolution and this also helps with heat dissipation. On the other hand, two flute 
mills are easier to sharpen and are quite a bit cheaper. In addition most two flute 
mills are center cutting and can do plunge cuts while most four flute mills are not 
center cutting (but, four flute mills which can center cut are available). So, 
except for cost and ease of sharpening, I would normally chose a four flute over a  
two flute. I look forward to seeing the other responses.

Roger Weppelman

---

From: [email-masked] (John Ingham)
Date: Wed, 03 Jul 1996 01:01:26 GMT

On Tue, 02 Jul 1996 17:09:47 GMT, [email-masked] (John Dammeyer)
wrote:

>Hi,
>Pioneers are the ones, face down in the mud,
>with arrows in their backs.
>Automation Artisans Inc.      Ph. 604-544-4950
>6468 Loganberry Place         Fax 604-544-4954
>Victoria BC CANADA V8Z 7E6
>
Two flute EMs are for softer metals, alu, copper, brass etc. They have
more chip clearance and rake and are used at higher speed and feed
rates for higher cubic inch per minute metal removal rates... they
tend to carve out material... much like a wood carvers tool. The four
or more fluted tools are generally for harder materials...stainless
steel, steel, monel and are  at slower speeds and are closer to
pushing the metal off due to rake although still very positive not
nearly as much as two flutes end mills. Careful examination of mill
geometry to match material being cut is one of many things a good
machinist watches for.
Machinists Exchange Online

On the Web:
http://www.machinists-exchange.com

email:
[email-masked]

---

From: Leonard Dye <[email-masked]>
Date: 3 Jul 1996 01:36:29 GMT

>when and why would I use each?

Typically a four flute end mill is used for steels and two flutes are 
used for aluminum. Higher chip loads are obtainable when machining 
aluminum and the two flute has additional chip clearance in the flute 
trough to prevent overloading. A four flute end mill will have additional 
strenght needed for the higher cutting forces of steels.

-- 
Leonard Dye
[email-masked]

innovative CNC machine tools
http://home.earthlink.net/~xltool/
Flush-Cut coolant induced milling adapters

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From: [email-masked] (John Dammeyer)
Date: Tue, 02 Jul 1996 17:09:47 GMT

Hi,

Thanks,
John

---

From: edwin bailen <[email-masked]>
Date: Thu, 4 Jul 1996 19:28:23 -0500

> two flute. I look forward to seeing the other responses.
There was a posting here a few months back that pointed out that the 
two-flute design is best for slotting.  When slotting with two flutes, only 
one edge is cutting at a time and the direction of the tool can be easily 
controlled.  With four flutes, more than one edge is cutting, and the 
tool tends to walk sideways.

At least that's what I think I remember reading.

Ed Bailen

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From: [email-masked] (Mark Fraser)
Date: 5 Jul 1996 04:35:23 GMT

4-fluters have a flute at 90 degrees to the flute currently at the deepest 
point of cut [sideways] - it helps to push the cutting flute into the
workpiece, making for grabbing in softer metals....  pretty much as the
other responders have said.  I experienced this first hand trying to make
some cuts for a spline.....  won't try the 4-fluter again.... at least not
without extra rigid everything....
/mark

edwin bailen ([email-masked]) wrote:

: On 2 Jul 1996, Roger M Weppelman wrote:

: > >
: > >Anyone why both two and four flute end mills are available.  Where and
: > >when and why would I use each?
: > >
: > >Thanks,
: > >John
: > >
: > 
: > 
: > John,
: > 
: > It is a good question. I am no expert but here is the way I see it. Four flute mills 
: > can cut faster since they bring to bear twice as many cutting surfaces per 
: > revolution and this also helps with heat dissipation. On the other hand, two flute 
: > mills are easier to sharpen and are quite a bit cheaper. In addition most two flute 
: > mills are center cutting and can do plunge cuts while most four flute mills are not 
: > center cutting (but, four flute mills which can center cut are available). So, 
: > except for cost and ease of sharpening, I would normally chose a four flute over a  
: > two flute. I look forward to seeing the other responses.
: > 
: > Roger Weppelman
: > 
: > 
: > 
: There was a posting here a few months back that pointed out that the 
: two-flute design is best for slotting.  When slotting with two flutes, only 
: one edge is cutting at a time and the direction of the tool can be easily 
: controlled.  With four flutes, more than one edge is cutting, and the 
: tool tends to walk sideways.

: At least that's what I think I remember reading.

: Ed Bailen

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From: [email-masked] (Justin Crom)
Date: 5 Jul 1996 20:01:00 GMT

In article <[email-masked]>, [email-masked] says...
>without extra rigid everything....
In his workshop book, the late G. H. Thomas provides an interesting analysis of 
2 lipped vs. 4 lipped cutters.  As several have mentioned here, the 2 flute 
variety is recommended for slotting.

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From: PPIERCE <[email-masked]>
Date: Fri, 05 Jul 1996 16:39:04 -0700

Justin Crom wrote:
> 
> In article <[email-masked]>, [email-masked] .....
> ..... mentioned here, the 2 flute variety is recommended for slotting.

I took me quite a while to figure out what Lautard meant by "slot drills"

Paul in AJ AZ

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From: [email-masked]
Date: Sun, 07 Jul 1996 12:42:12 GMT

>Victoria BC CANADA V8Z 7E6
i hardly ever use 4 flute mills. the two flutes are much stronger an
will hog metal much faster. in soft metals 2 flute is the only choice
for anything except playing around.  in a  shop where time is money
the mills are allways pushed to the limit. everyone i know has found
that 4 flute load up easier, break easier. the only time i use 4 flute
is when i'm facing off ends of parts that are 2-4 inches thick in one
pass, then i use a long 3/4 or 1' 4 flute. well anyway it seems to be
personal choice does'nt it? what about 3 flute? are they the happy
middle? 

danny