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The brother of one of my ex-wives, works for an industrial supplier, that sells machine shop supplies and equipment, in Central and South American, they don't actively sell in the US. We were friends before, I married his sister and remained so after the divorce. From time to time, he sends me samples, I buy overstocks and generally get a big box of stuff, for a small cash outlay.
A while back I bought about 100 HSS end mills, in 1/4", 5/16", 3/8", 7/16" and 1/2" sizes (for about $1/ea). They are sourced out of Korea, in a plain plastic sleeve, with only the size and Korea on the shank. According to the ex-BIL, they are mid-grade, meant to be private labelled by the end supplier, as their house brand. I been using them and they (at least for me) have been great. When I opened a tube this weekend for a small job, I noticed something I hadn't seen before.
I opened a 3/8" tube, out popped a 3/8" HSS end mill with a 1/2" shank, I looked at a couple of others, some were 3/8" with a 3/8" shank, and (2) were 3/8" with a 1/4" shank. Almost all of the other end mill I have in the shop, have a cutter and shank the same size, a few of the 1/8" and 3/16" I have are on 3/8" shanks. Now the question, is it common to offer all these different shank sizes? Is it so, you can limit the number of collets needed?
If you set them side by side the fluted end seem identical, same helix, same cutter edge shape the only difference seems to be the shank. I have lots of collet so they are all usable, but the shanks are different.
I'd post a picture, but I'm in Northern Vermont, working for the Great State of Vermont (their words not mine).
I do appreciate your responses.
jack
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Jack,
I've seen the different size shank thing with metric tools but rarely with inch sized ones over 1/4" cutting diameter. Usually when you see that it's a case of using a larger diameter shank on end mills well under 1/4". I have some a 3/16" mill with a 1/4" shank, and many different sizes under 1/8" that all have 1/8" shanks, including the (5) 1/32" solid carbide end mills I'd recently bought.
My theory is that the larger shanks make it easier to control runout from grinding when it's a bigger shank and holder.
Ken
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(01-12-2015, 07:55 PM)the penguin Wrote: I'd post a picture, but I'm in Northern Vermont, working for the Great State of Vermont (their words not mine).
Jack, does the "Great State of Vermont" not allow pics? 
Steve
Busy Bee 12-36 lathe, Busy Bee Mill drill, Busy Bee 4x6 bandsaw, Homemade 9x17 bandsaw, Ad infinitum.
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The following 2 users Like the penguin's post:
EdK (01-13-2015), PixMan (01-13-2015)
(01-13-2015, 07:55 AM)stevec Wrote: (01-12-2015, 07:55 PM)the penguin Wrote: I'd post a picture, but I'm in Northern Vermont, working for the Great State of Vermont (their words not mine).
Jack, does the "Great State of Vermont" not allow pics?
Steve
I'm in the Great State of Vermont, the end mills are in the shop back in Syracuse. That would take an incredibly big telephoto-lense to see them from here
jack
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(01-12-2015, 11:30 PM)PixMan Wrote: ..... and many different sizes under 1/8" that all have 1/8" shanks, including the (5) 1/32" solid carbide end mills I'd recently bought.
My theory is that the larger shanks make it easier to control runout from grinding when it's a bigger shank and holder.
Ken
Just curious Ken, but what kind of machine do you have that has the spindle bearings/run out, rpm, and feed rate necessary to be able utilize a carbide end mill of that size? You been holding out on us?  
Willie
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(01-13-2015, 10:10 PM)Highpower Wrote: (01-12-2015, 11:30 PM)PixMan Wrote: ..... and many different sizes under 1/8" that all have 1/8" shanks, including the (5) 1/32" solid carbide end mills I'd recently bought.
My theory is that the larger shanks make it easier to control runout from grinding when it's a bigger shank and holder.
Ken
Just curious Ken, but what kind of machine do you have that has the spindle bearings/run out, rpm, and feed rate necessary to be able utilize a carbide end mill of that size? You been holding out on us?
You've seen it. My milling machine is a 1983 vintage Alliant that is a Taiwanese made Bridgeport clone with a top speed of 4500 rpm. Nowhere near proper speeds for a 1/32" (0,8mm) carbide end mill, but I got the pack of 5 for less than one good HSS end mill.
When I used one of them recently I had the rpm up at top end and was very surprised that I didn't break the end mill going that slow. It actually cut pretty nice.
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(01-14-2015, 08:12 AM)PixMan Wrote: Nowhere near proper speeds for a 1/32" (0,8mm) carbide end mill, but I got the pack of 5 for less than one good HSS end mill.
When I used one of them recently I had the rpm up at top end and was very surprised that I didn't break the end mill going that slow. It actually cut pretty nice.
That is what I was curious about. From what I have read in the past, if you aren't running a bazillion rpm and a consistent micro feed rate, it's sure death for a carbide tool that small. Just how slow of a feed can you get on your mill?
I was just wondering how you managed to pull it off. I've tried it myself in the past. Of course I don't have anywhere near the mill you do, and the instant the tool lightly touched the part it snapped off like a strand of glass thread. Which was just what I expected to happen honestly. So what is your secret to success if I may ask?
..... DOH! It just occurred to me you have a CNC setup. Never mind. 
Move along folks, these aren't the droids you are looking for....
I have been toying with the idea of getting the speed increasing hand piece (35,000 rpm) for one my Foredom tools and mounting it to the quill of my mill and giving that a try. I would still have a problem with the feed rate, but thinking I may be able to get away with something like "chain drilling" a slot first then going at a finish pass? I dunno.... 
Willie
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Willie,
I didn't use the CNC of my machine with the 1/32" end mill. The operation I used one on was that "sight leaf" that I'd made for dallen, milling the graduations. While the end mill was cutting full width is was only .0075" (about 0,2mm) deep.
I fed it by hand on the job.
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did a damn fine job of it too if I may say so!!!
Dallen
dallen, proud to be a member of MetalworkingFun Forum since Apr 2012.
If life seems normal, your not going fast enough! 
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The following 1 user Likes Highpower's post:
Mayhem (01-15-2015)
(01-15-2015, 07:40 AM)PixMan Wrote: Willie,
I didn't use the CNC of my machine with the 1/32" end mill. The operation I used one on was that "sight leaf" that I'd made for dallen, milling the graduations. While the end mill was cutting full width is was only .0075" (about 0,2mm) deep.
I fed it by hand on the job.
Ahhhh, OK. Still, you must have a very deft touch on the handles. 
I equate that to drilling a #80 sized hole on the mill using the quill feed. You certainly can't "feel" how much pressure you are putting on the drill with all that mass. (Thank goodness for sensitive drill chucks!)
Even at a .0075" DOC, it takes some real talent and experience to not have snapped such a tiny carbide tool.
Ditto on what David said about the job you did on his sight ladder. Excellent. 
Willie
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