Fly Cutter Vs. Face Mill

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phillip
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Fly Cutter Vs. Face Mill

Post by phillip » Sat Sep 01, 2012 8:16 pm

When squaring and such, What is better, Fly or Face? Is one better than the other?

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GlennW
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Re: Fly Cutter Vs. Face Mill

Post by GlennW » Sat Sep 01, 2012 8:26 pm

One is a whole lot cheaper!

A fly cutter is easy to make and grinding a HSS cutter for it is too.
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!

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Richard_W
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Re: Fly Cutter Vs. Face Mill

Post by Richard_W » Sat Sep 01, 2012 11:23 pm

The first question is what kind of mill you got?

If you don't have the power or rigidity to run a face mill, then one isn't going to do you any good.

Fly cutter is good for a fine finish, but is slower due to only one cutting edge. Face mill goes much faster and works fine for most things you would do. Question is how big a face mill can your machine handle? Since we don't know what you have we really can't say.


Richard W.

phillip
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Re: Fly Cutter Vs. Face Mill

Post by phillip » Sun Sep 02, 2012 9:12 pm

Richard_W wrote:The first question is what kind of mill you got?

If you don't have the power or rigidity to run a face mill, then one isn't going to do you any good.

Fly cutter is good for a fine finish, but is slower due to only one cutting edge. Face mill goes much faster and works fine for most things you would do. Question is how big a face mill can your machine handle? Since we don't know what you have we really can't say.


Richard W.


Bridgeport Clone (Induma) 1.5 Horse J Head.

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GlennW
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Re: Fly Cutter Vs. Face Mill

Post by GlennW » Sun Sep 02, 2012 9:40 pm

Probably up to a 2" face mill and still take a decent cut.
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!

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mechanicalmagic
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Re: Fly Cutter Vs. Face Mill

Post by mechanicalmagic » Sun Sep 02, 2012 10:34 pm

phillip wrote:Bridgeport Clone (Induma) 1.5 Horse J Head.
Not a very active bunch, probably off for the long weekend.
I'll throw out my thoughts on the three types of cutters. I say three, because that's really what you have.
#1 is a flycutter. Typically a single cutting tool spinning around throwing chips all over the shop. They are inexpensive to operate, since the cutting edge is usually resharpened. A long swing allows a large surface to be cleaned up rather quickly. Heavy cuts are not usually an option, since it beats the gears in the head. Carbide lathe tools work fine for steel, HSS is my preference for Al. Good for a quick skim. Easy to make your own.

#2 is a carbide insert face mill. You have the power to run one, if you can dodge the flying blue chips. I think you can remove 1.5 cubic inches (steel) per minute with your mill. This is more of a production application, since you will be using up edge$ of carbide insert$. With the proper choice of insert, a tremendious amount of Al can be removed very quickly.

#3 is the HSS face mill (shell mill). I avoid these. Expensive, but can be re-sharpened. Requires a special holder.

Dave J.
Every day I ask myself, "What's the most fun thing to do today."
9x48 BP clone, 12x36 lathe, TIG, MIG, Gas, 3 in 1 sheetmetal.

JTiers
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Re: Fly Cutter Vs. Face Mill

Post by JTiers » Mon Sep 03, 2012 8:22 am

For me, the HSS shell end mill is the cheapest....... I have all sorts of sizes of them. I may still have the 6" diameter rougher, but I might have given that away. Tooling that is viewed as "obsolete" can be very cheap, almost free.

They are functionally equivalent to the carbide face mill, but do not have the issues that carbide has in terms of speed for good finish, etc.

Finish can be mirror-finish almost.... depending on material, speed, and feed. I got very good finish on some aluminum, which is likely the last time I took a pic when used them. (front face of this part)

Image

Holders for shell end mills are fairly easily made, at least I can make them, so you can too.

Image

Image

Image

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Richard_W
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Re: Fly Cutter Vs. Face Mill

Post by Richard_W » Mon Sep 03, 2012 11:59 am

Shell mills have there place and do work good. Trouble is you need several for when one gets dull and needs to be sent out to be sharpened. I like them, but I use carbide face mills the most.

A 2" face mill as mentioned would be ideal, if you were going to only have one face mill.

On the other hand an 1 1/2" face mill works good for getting excess material out of the way. I use one that takes three of the TPU322 inserts. It also works fine for finishing, but a fly cutter will give you the best finish with a properly ground tool.

I also use a 2 1/2" face mill that takes four TPU322 inserts. The disadvantage is due to it's size you are limited to about 1/16" cut. That is where the 1 1/2" face mill comes in to remove the excess material out of the way quickly.

Actually you will want face mills and a set of fly cutters. Fly cutters are limited by your imagination to cut angles, radius or even small dovetails with properly ground tools. Several sizes are nice to have for those odd ball parts that come along. You can see in the photo pretty much the basic needs that have served me well for several decades. The large fly cutter is new as I decided I needed two of them. It has a 3/4" shank and is 3" in diameter that takes 1/2" tools and is U.S. made. I threw the boring head in the photo just because you will probably want one of those down the road, if you don't already have one. The reason for the 3/4" shank on the boring head is it allows me to use it in other machine that have a # 40 or# 50 taper. An R8 shank would limit where I could use it.

Richard W.
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