Face Mill Heads - how useful are these two

[7milesup]

Hi guys. I purchased these two face mill cutters on an auction a while ago. They must have been in a box of other stuff I wanted needed because I don't recall specifically looking for face mills.

I have a Sharp mill with R8 and ER40 tool holding capability.

The first one is a 4" Octo mill. SECO R220.43-04.00-07S Here is a link to a description of the cutter (although that one has a W suffix whereas mine has an S). According to the SECO website, the interface is for a Cat40, C6, C8, and a few others that I have no idea what they are.

The second one is a Kennametal KSHR200HN5345C3. Here is a link to this one. It is a 2" Kennametal Dodeka that will interface with R8 and other machine-side systems.
I know very little about face mills (shell mills?), but one thing I did notice is the 4" one has a rather significant "positive" rake to the cutters, whereas the 2" cutter has a "negative" rake.
So, the question is, what do I do with these? It seems that the 2" cutter would be great for my mill, whereas the large one is maybe for a large Haas or other very rigid CNC machines.

 

[cathead]

You could make some holders in R8 or in ER40. It's not that hard to do. It would be a few enjoyable hours
spent in the shop and the end result would be that your machining capability and ability too would be enhanced.
I think your mill would power any of them.

 

[JimDawson]

The 4'' face mill would just tear up your machine. It needs at least a 40 HP spindle and a machine to match to really use it properly. The biggest face cutter we use on the Haas (7.5 HP) is 1.5'' and only in aluminum.

The 2'' would work OK on your machine for very light facing cuts. I have a machine about the same size as yours, and I do have a 2.5'' facing cutter. It only gets used for very light facing cuts, not more than about 0.025'' DOC. I bought it specifically to make skin cuts for a job on aluminum bar stock that needed a specific surface finish and texture. Rarely do I use cutters >1/2'' dia.

 

[benmychree]

A shell mill arbor should be available for any of the cutters. The term shell mill applies to HSS tools, The term face mill is usually applied to carbide insert cutters such as you show.

 

[KC36330]

the positive rake makes a great finish cut, it can't take a heavy cut so the demand of your machine isn't high, the negative raked is just the opposite, it's designed for removing material and needs power and stability so the 4" would be more ideal for keeping IMO then the smaller negative raked... i don't know your machines capabilities, just speaking in general.

 

[7milesup]

the positive rake makes a great finish cut, it can't take a heavy cut so the demand of your machine isn't high, the negative raked is just the opposite, it's designed for removing material and needs power and stability so the 4" would be more ideal for keeping IMO then the smaller negative raked... i don't know your machines capabilities, just speaking in general.

The 4'' face mill would just tear up your machine. It needs at least a 40 HP spindle and a machine to match to really use it properly. The biggest face cutter we use on the Haas (7.5 HP) is 1.5'' and only in aluminum.

The 2'' would work OK on your machine for very light facing cuts. I have a machine about the same size as yours, and I do have a 2.5'' facing cutter. It only gets used for very light facing cuts, not more than about 0.025'' DOC. I bought it specifically to make skin cuts for a job on aluminum bar stock that needed a specific surface finish and texture. Rarely do I use cutters >1/2'' dia.

Hmmm. That looks like two opposing views.

I realized that I did not include a very good picture of the 4" face mill and associated rake angle. I consider that a "positive" rake angle. Just want to make sure I have the terminology correct.

 

[JimDawson]

Here is a pretty good explanation from my friend Google. http://www.minaprem.com/machining/c...itive-rake-negative-rake-and-zero-rake-angle/

My comment is based more on the cutter diameter than anything else. It's just too large for your machine. The required torque increases roughly as a function of the square of the diameter.

 

[Winegrower]

I imagine Jim is correct for getting the total performance from that 4”. However, I have a 5” face mill, and it works great on the bridgeport for surfacing steel or aluminum, where I take pretty shallow cuts, maybe 0.01“. I like it because for most sized parts I make there are no lap lines, and on bigger parts fewer of them.

 

[KC36330]

Hmmm. That looks like two opposing views.

I realized that I did not include a very good picture of the 4" face mill and associated rake angle. I consider that a "positive" rake angle. Just want to make sure I have the terminology correct.
View attachment 418488

i'll stick to my original point of view. i guess it's more a personal preference, more cutting edges so less heat, and at the end of the day a much better finish at the cost of a shallower DOC....

 

[davidpbest]

I have a Haas 4" face mill that I use on my (less than Sharp rigidity) PM-935 mill, and it has a positive rake octagon insert like the ones you show. The limitations of a face mill this size on Bridgeport-like machine is depth and width of cut. With the 4" on my PM-935, I can easily plow off 0.100" depth of cut, full diameter in 6061. In 1018 or 303 the limit is more like 0.020" DOC before the machine is thrown out of tram. That said, I have found that a 2" face mill is more appropriate for harder materials on this type of mill. Several videos among these photos that demonstrate use of both 4" and 2" on my baby Bridgeport are here if you're interested.