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ligito
05-02-2007, 08:37 PM
I need to buy some end mills and I can't find the thread from a couple of months ago that gave some sources.
I have been looking at Enco but am unsure of what to buy.
I would like to get some starter sets, or individual mills in both double end and single end. I plan to cut steel and would like to have some center cutting abilities.

Should I get carbide?
3/16--7/16
Any suggestions for some low cost mills and types?
And what is available for angled edge milling, or is something else used for this?

Mark Hockett
05-02-2007, 08:59 PM
ligito,
What type of machine will you be using the end mills on? Most carbide EM's need higher RPMs, accurate chip control and a very rigid machine or they will chip. HSS EM's are much more forgiving, especially if you are just learning and tend to run at slower then normal speeds. Good quality HSS end mills will give you lots of service if used properly.

Carld
05-02-2007, 09:38 PM
For general machine work use HHS or Cobalt. Carbide chips to easy for general use. If you live in a large city or close to a tool regrinding shop call them. They may have regrinds that they can sell you.

ligito
05-03-2007, 12:43 PM
I'm a beginner, with a Jet JMD-18 Mill/Drill and I run it as slow as it will go.

I used a 5/16 carbide end mill the other day and destroyed a 1/2 in steel part, as I didn't see that my table feed was still moving. It sure did cut real fast. Not at all like the HSS that I used earlier.

Are there any Enco part numbers you'd suggest?
I will call my local saw sharpener to see what they have.

SGW
05-03-2007, 01:12 PM
While you're learning, "quality import" HSS end mills may be the way to go. Then when you whack them (you will), you won't feel so bad. As you gain experience, you'll get to the point where you'll be able to appreciate the superior performance of top-quality end mills (Niagara, Weldon, Putnam, etc.) and they'll last long enough to make the extra cost worthwhile.

Coated end mills can be an advantage, but I get the idea that a lot of cheap end mills are coated in an effort to "powder the pig" and make them seem better than they are. Coating a poor-quality end mill doesn't make it a good end mill.

I don't have much experience with carbide end mills.

Get a copy of the MSC catalog www.mscdirect.com and the Travers catalog www.travers.com for more extensive selections.

hitnmiss
05-03-2007, 01:15 PM
Good quality EM in HSS are somewhat spendy. I use the ATRAX enco brand (all carbide I think) and like them OK (older cnc Bridgeport but still fairly tight)

I've had a few OSG HSS end mills that you have to be carefull pickng up they are so sharp, cut very well.

I'd give the ATRAX a try.

Mark Hockett
05-03-2007, 08:20 PM
ligito,
The way my shop works is I have different end mills for different applications. I keep the cheap import end mills for what I would call utility use, such as cleaning up a chunk of steel thatís been welded on or any use where I might damage the cutter. These would be like the Enco import cutters that usually run about $3.00 for a 3/8" EM. Enco sells these in sets, which include many sizes in 2 and 4 flute styles. Enco has the 10 pieces 3/16" to 3/4" sets on sale for $19.99 in 2 flute and 4 flute styles. That might be a good place to start until you learn to control the feed and how much depth of cut to take. Then add better quality EM's when you need them. It wont hurt the pocket book so bad throwing a $2 EM in the trash instead of a $25 one if you crash it.

I also stock good quality HSS cutters. I use these on my manual mill and on plastic in my CNC mills. One brand I like is YG but there are many brands available that work just as well. These EM's will usually cost $8.00-$25.00 for a 3/8" EM. These usually have a noticeably better finish and require less force to cut due to the better cutter geometry. The Enco equivalent would be the Putnam brand. The OSG cutters are very nice too.

I also stock many different carbide EM's. These days in a production environment it is important to have the proper EM for the type of material being cut. On my CNC mill my speeds and feeds are a lot different from what you would use on your manual mill. On aluminum I use one spindle speed for all carbide cutters up to 3/4", 7500 RPM, thatís as fast as my machine spins. I just adjust the feed rate so that I have the correct chip load for the size of cutter. The job I am running right now is using a 3/8" 3 flute EM running at 7500 RPM, 160" per minute and .4" depth of cut. I have run about 900 parts; the cutter looks like new and is still sharp and making perfect cuts. The same cutter would last about 15 minutes on a manual mill. For aluminum I usually use 3 flute uncoated end mills. For steel and stainless I use 3, 4 and 5 flute ALTiN coated EM's.
One of my favorite carbide cutters is the Swift Carb brand, (http://www.swiftcarb.com/)
I don't like the Atrax cutters. I was using a brand new one on my CNC mill and it was chattering and leaving a poor finish, I switched to a Swift Carb EM and kept all the speeds and feed the same. The chatter went away and the finish was better. I then was able to speed the feed up another 50% and the cutter still worked great.

I also stock the cutters in different helix angles. I use low or moderate helix cutters for roughing and high helix cutters for light finish cuts.

Like I said what works for my shop is not the same as what will work for yours. Many people think that carbide is the answer. If you are using a manual mill you most likely will have to use the conventional cut direction when cutting. CNC machines use a climb cut direction when cutting. When using a conventional cut you recut many of the chips, which is very hard on a carbide EM. Climb cutting ejects the chip better so you don't recut chips as much.

I hope this helps you make a decision,

Carld
05-03-2007, 10:38 PM
I don't think you will find end mills at a saw gringing shop. You will have to look for an industrial tool grinding shop.

ligito
05-05-2007, 02:00 PM
I don't think you will find end mills at a saw gringing shop. You will have to look for an industrial tool grinding shop.

You're right, they didn't have any.

timcasbolt
05-05-2007, 09:57 PM
You can often get end mills on ebay that are worth the trouble. Picked up 10 reground 1/2" carbide recently that were about 15/32". Single end, center cutting. $20 plus about $8 or $10 for shipping. Great for general purpose hogging or whatever. Many other deals out there if you look, but it's definitely buyer beware.

BadDog
05-05-2007, 11:20 PM
Look to your local surplus shops. Or friends working in CNC shops. Either source will likely be able to get you cutters that were pulled on a time table. Production CNC shops can't afford to run a cutter till it dulls, chips or breaks. If they did, they would get too much scrap. So they evaluate the minimum amount of time they can expect a cutter to last, and pull them at that sweet spot. Cutters are too cheap to risk scrapping 10 parts because you didn't know the cutter was dull/chipped and the finish it ruined. Many of these are still perfectly good, and I can get top quality US made 1/2" solid carbide 3 flute rougher's for about $7 each all day long. Smaller are cheaper of course. You can also get resharps about the same price. In that case, they apparently have some tolerance that is required. Some of the shops send cutters to resharpen, but they wind up a bit under tolerance and the shop wouldn't run them. I've got some like this too, you just can't count on the diameters since they are 0.010 or more undersize.

I've got probably 50 lbs of carbide cutters in my box. Only down side is you don't find HSS like this. <shrug> I'm generally happy to run top grade carbide for less than most comparable sized ChiCom HSS bits. The major problem here is that I can't run anything smaller than 1/4" fast enough on my Bridgeport, and 1/4" is really too slow.

So, I do have HSS that I've picked up at machine shop auctions (from their tool room supply) and surplus (indirectly coming from the same sources). I wouldn't want to be completely dependent on carbide as sometimes it's clearly NOT the right choice. So I've got several dozen different HSS cutters too, most cost me under $4 each, some much less.

Buckshot
05-06-2007, 07:14 AM
........Hi, my name's Rick and I'm an endmill junkie :-) Endmills are completely fascinating to me. Kind of like jewelry to women I suppose. I won't even have a competant milling machine until probably the spring of next year. All I have now is a milling attachment for my lathe, and the mill portion of a bottom of the line Harbor Freight mill/lathe combo machine.

But for the past 3 years that hasn't kept me from accumilating a very wide variety of endmills, from an equally wide group of sources. I probably have 50 lbs of Boeing re-sharps, which for a hobbiest are super. They were high quality to start out and were nicely re-sharpened and then dipsealed. Some sharp cornered, some radiused with the info on sticky paper under the dip seal.

Then a bunch of brand new Hanita, Niagara, Weldon, Putnam, Fastcut, Cleveland, OSG, etc. It seems on E-Bay that sometimes you're the only one there bidding on endmills. Not too often, but it happens. My biggest coup was a couple years ago when I got 4 new Hanita 4 flute, 1" centercutting endmills for $18. What in God's name I'd ever do with them I don't know but they sure are pretty!

A good thing to do would be to get yourself a book on cutting tools. I have one from Bendix that was printed in the early 80's, but so far as HSS goes is still current. It deals in great depth with drill, taps, reamers, and endmills, SPM, feeds, DOC's chip loads and etc & etc.

Also, do NOT toss broken endmills. They can be ground into great boring bars, and lathe tools. The shanks may be cut off and used for locating dowels, punches and such.

Rick

cybor462
05-06-2007, 11:30 PM
Heah Rick the next logical step for you is to sharpen them. I would send you loads. I bought all kinds off ebay and most said sharp or resharpened and what I got was dull burnt cutters.

I am sure many others would do the same. Make your love of EM payoff!;)