End mills.. need help.

My rule of thumb for tightening a drawbar is finger tight, followed by between a half- and two-thirds of a turn with the vise or drawbar wrench, while holding the brake of course. Usually I just do about a half turn. Over-tightening, of course, can break drawbars or strip threads.

But as to the OP - a set of collets will do you just fine. If you were to get a roughing end mill - then I would consider a solid holder. But even then, I wouldn't worry too much about it.

For types of end mills - square or flat end mills are for standard work. They are what you need most of. Ball-nose end mills create a whole radius - a 1/2" ball end mill will make a 1/4" radius or half of a 1/2" diameter. Not really too useful unless you need radii, or in 3D contour milling on a CNC... neither here nor there.

But a bull nose end mill, or a corner radius/chamfer end mill, can be useful. These are flat end mills with a small radius or chamfer on the edge. This results in a stronger edge, allowing higher feed rates without chipping. Then again, on a smaller machine, it can also induce chatter.

If I was you starting out, I would buy one of the common sets of 2 and 4 flute end mills you see on Enco all the time - they go from 3/16 to 3/4 diameter. Buy a set of collets that accompany that set of end mills - the shanks are 3/8, 1/2, 5/8, and 3/4. That'd be somewhere around $120. That would get you started in terms of milling cutting tools and holders.
 
Every tool shop I have worked in had a set of end mill holders and they all had a hefty layer of dust on them from lack of use! And all used the R8 collets except for one 1947 South Bend mill, now in my possession, that used a pain in the neck mongrel collet system.
We did use a holder once because for some reason, and I can't remember why because it was probably 40 years ago, we needed the extra reach.

The biggest problem I encountered was apprentices over tightening collets to the point you needed a hammer to loosen them. We had one kid who couldn't have weighed 120 pounds soaking wet but he could tighten a draw bar so tight it would make your eyes bleed trying to loosen it. A couple of good raps on the knuckles helped considerably (probably not an acceptable cure these days!)

John
 
I origionaly used mt3 collets when i got my bench mill, i would change to a chuck for any drilling, that changed the height a lot and required putting the head up to give room for chuck and drill bit, now i hold everything in an er32 collet holder that goes in the mt3 spindle.

holdes from 2mm to 20mm with no gaps. I havent had anything come lose on me yet.

Stuart
 
I have the same mill. I use an R8 chuck holder for ER32 collets.
Work great, have never had a problem.
Jim
 
So my finalized starter tool list is as follows. PLEASE chime in if there is something really important missing.

1Set of 2&4 flute Endmills HSS-TiN

1 set of small and one set of large ball tip endmills. The large set has 7/8" shanks.

1 3/4" chamfer tool. I assume it can chamfer from 3/4" max size and down (smaller chamfers). If I am wrong please let me know!

1 set of fly cutters with 3/4" shanks... and a piece of tool steel.

I'll be using R-8 collets.

I have a milling book with a project for making a boring head, so I plan to make that and save the money.

With any luck, I should be ordering the machine and all the other goodies Monday or Tuesday.
 
Did I miss seeing a call out for a work-holding device? You'll either need a vise (4" or 5" most likely) or a clamping set of some sort.

I got the 10 piece 2/4 flute cutter set from Grizzly when I bought my prior mill, and it's been fine. Enco right now has a 20%+free shipping sale until Sunday night in case you can't get it all from Grizzly or HF. Way oil and cutting oil would be good investments.

Are you doing Harold Hall's boring head project? That's the one I did, but I don't see it saving you much money (if that's your goal.) I probably spent $80 in materials (which included the R-8 arbor), and you can buy a MIC set for that much. However, mine works really well, I'm proud of it and it was a terrific project. You can see the results in this thread: http://www.hobby-machinist.com/showthread.php?t=22120

-Ryan
 
Pat of TN said:
But a bull nose end mill, or a corner radius/chamfer end mill, can be useful. These are flat end mills with a small radius or chamfer on the edge. This results in a stronger edge, allowing higher feed rates without chipping. Then again, on a smaller machine, it can also induce chatter.

If I was you starting out, I would buy one of the common sets of 2 and 4 flute end mills you see on Enco all the time - they go from 3/16 to 3/4 diameter. Buy a set of collets that accompany that set of end mills - the shanks are 3/8, 1/2, 5/8, and 3/4. That'd be somewhere around $120. That would get you started in terms of milling cutting tools and holders.
Click to expand...

Which Enco set would you recommend? I can't find anything in their catalog with a bull nose other than lathe tooling.

Thanks!
 
You must log in or register to reply here.
Back
Top