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torker
02-05-2012, 10:32 AM
Hey guys! Just wondering...what is the limit on size for shell mills/face mills for 40 taper verticle (turret)mills?
I'd really like to have another 50 taper horizontal but a verticle would be handier overall. I have some of my 50 taper tooling left and a couple of 6" shell mills that I really like. I'm bettin they'd be too big for a 40 taper setup tho??????
Thanks!
Russ

PixMan
02-05-2012, 10:56 AM
The size you use isn't as much a factor as is how much LOAD you put on it. How much HP does the 40 taper spindle have at hand?

On a typical 15 or 20HP CAT40 spindle, I usually see nothing bigger than a 4" cutter, sometimes only 3". That may have as much to do with the distance between toolchanger pockets as it does cutter efficiency and diameter.

What machine and how much torque/HP is there? Does it have a toolchanger to be concerned about?

torker
02-05-2012, 11:06 AM
I realize that I can put a 2 foot diameter cutter on any mill...and not cut with it. I'm just asking what would be typical on a turret mill...guess I shoulda said...in the 2 to 3 hp range. BTW..I ran these shell mills on an old horizontal with 3 hp and they worked great. And no...there is no tool changer...just a plain old manual turret mill I'm thinkin of buying.
Thanks!
Russ

wierdscience
02-05-2012, 11:38 AM
Russ,on our old Polamco mill at work I have a 4" and a 6" and seldom ever run the 6"
The machine is NT40 taper both vertical and horizonal with the vertical spindle being 3-1/2hp IIRC.

These shell mills are nice-

http://www.glacern.com/fm45

Black Forest
02-05-2012, 11:44 AM
What is the difference between a shell mill and a face mill?

wierdscience
02-05-2012, 11:48 AM
What is the difference between a shell mill and a face mill?

IIRC a Shell mill is one where the shank is a seprate piece from the cutter itself and a Face mill is one type of Shell mill.

There are also Shell Reamers where the shank is a seperate piece from the Reamer itself.

PixMan
02-05-2012, 12:11 PM
Shell mills are usually high speed steel cutters which have a precision ground bore and counterbore to mate with the pilot diameter and cap screw of a shell mill holder. I found lots of HSS shell mill images using Google Images, but wasn't inclined to copy and paste them.

Face mills are now usually carbide insert cutters that use shell mill arbors for mounting, and the term is most-often used when referring to a 75º, 45º or other lead angle type of mill rather than a 90º shoulder mill. You can mill a face with a shoulder mill, but you can't mill a shoulder with a face mill!

BTW, those FM45 face mills are OK for sub-5HP machines, but I have two friends (who both own small job shops) who have stopped using theirs on there 7.5 and 10HP CAT40 spindles. The cutters seem to be a little weak in the insert pocket. Note the close-up of cutter where it shows the insert nested in the pocket with just a thin strip of metal to register the insert edge, but a relatively large diameter hole drilled as a corner relief. I'd shop for a good (if used) Coromant R245, Kennametal KSSR, Valenite VSR or Walter F2334 if I wanted something that could take an accidental hit or insert failure.

wierdscience
02-05-2012, 12:22 PM
Apparently the terms get used fairly loosely-

Insert Shell Mill-

http://news.thomasnet.com/fullstory/High-Feed-Shell-Mill-Cutter-yeilds-high-level-of-material-removal-584989

J Tiers
02-05-2012, 12:47 PM
Regular HSS shell mills and shop made holders


http://img.photobucket.com/albums/0803/jstanley/shellmillarb5.jpg

Black Forest
02-05-2012, 01:05 PM
Regular HSS shell mills and shop made holders


http://img.photobucket.com/albums/0803/jstanley/shellmillarb5.jpg


OK now I know what you mean. A Walzenfräser!

torker
02-05-2012, 01:07 PM
My favourite one is a Kennametal 6". It is listed in their catalog as a shell mill. I really don't care that it was meant for a 25 hp machine or whatever...it worked fantastic on my ol Ohio...top rpm 484. I kept it as I was hoping for another heavy horizontal one day.
I've never ran or owned a 40T vertical turret so I'm wondering if it would handle the cutter size ok with light cuts? Say .050 or so...
My Ohio could take .150 doc with ease but I'm not fooling myself when it comes to turret machines. I'm just trying to avoid another wimpy R-8. I kept a bunch of R-8 tooling as well but would like a heavier taper.

Black Forest
02-05-2012, 01:53 PM
Hey Torker, I have a horizontal mill I will give you. You just have to come get it. 7.5 hp MT5 tooling. I have lots of tooling for it. Power feeds and rapid traverse on XYZ. Only weighs around 4500 lbs. Then you can use your shell mill with confidence.

torker
02-05-2012, 02:06 PM
Hey Torker, I have a horizontal mill I will give you. You just have to come get it. 7.5 hp MT5 tooling. I have lots of tooling for it. Power feeds and rapid traverse on XYZ. Only weighs around 4500 lbs. Then you can use your shell mill with confidence.
He he...thanks! I just sold one awile back...weighed almost 7000 pounds....nice big 50T van Norman. I'd prolly need a boat to come get yours huh? LOL!

Black Forest
02-05-2012, 02:09 PM
NO a Ford dually would work.

torker
02-05-2012, 02:10 PM
NO a Ford dually would work.
Yabut...they get wet...

Black Forest
02-05-2012, 02:11 PM
Sillly boy, roll the windows up!

DFMiller
02-05-2012, 02:33 PM
Hold you breath and drive really fast.
Don't make any wrong turns and you will be fine.
Dave

dian
02-05-2012, 04:11 PM
hm, ill come and get it tomorrow, have you got a gablerstapler?

Black Forest
02-05-2012, 04:20 PM
No gabelstapler but I have a excavator that will lift it!

PixMan
02-05-2012, 05:15 PM
Perhaps a bit back on topic, but...

These are face mills, which just happen to be mounted on R8 shell mill arbors. Except, that is, for the smallest one. That one s an integral shank style.

http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/IMG_0988-r.jpg

torker
02-05-2012, 06:37 PM
Ya...seems funny that Kennametal still calls cutters similar to mine...Shell Mills...
http://www.kennametal.com/e-catalog/ProductDetail.jhtml?XMLArg=10632.xml&MMNumber=2881954&fromloc=srch&parentId=2881954&sid=null

wierdscience
02-05-2012, 09:25 PM
Perhaps a bit back on topic, but...

These are face mills, which just happen to be mounted on R8 shell mill arbors. Except, that is, for the smallest one. That one s an integral shank style.

http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/IMG_0988-r.jpg

Isn't that 4" one mounted on that R-8 shank just a little bit ridiculous?:)

hardtail
02-05-2012, 10:31 PM
Judging by wear the bigger they are the less they were used........?

I can't really say with my limited machining experience but I have some face mills in the 3" range on 40 and hp seems limiting......the more important factor maybe how many inserts are on it?.......Guess thats irrelevant on a shell mill since you can't change it.......

That said I've seen pics on here of someones homemade cutter out of a 12" flexplate or something for resurfacing cylinder heads and it seemed to prodice good results. I would have thought the flexplate would deflect too much but there wasn't many cutters IIRC.......

PixMan
02-05-2012, 10:41 PM
The big ones are indeed rarely used because:

a) I have a 1HP Bridgeport. All but the smallest one can bring the machine to its knees begging for mercy.
b) The two biggest ones were just about brand new when the photo was taken.

I've seen those 10" and bigger cutters for use on low HP machines for skim cuts on head and blocks. They usually have only one or two cutting tips, often just brazed carbide.