Good place for sourcing end mills?

GunsOfNavarone

GunsOfNavarone

Registered
Registered
Joined
Jun 26, 2018
Messages
1,733
I have researched enough about end mill materials, coating, designs and purposes that I have enough comfort there's that I won't those questions however, any suggestions on a place to get decent end mills? My used PM-727M came with some nice ones from a place local here Colorado Mold Supply. Seems to be too quality and great performance but possibly expensive to very expensive (here's a link, let me know your thoughts) I don't mind so much if the last/perform, but also I am a novice, mistakes will be made. I'm not sure I should experiment with a 75-100 dollar end mill.
Colorado Mold Supply,
A small set maybe a cost effective way, but haven't had much luck but with Amazon and those are probably Chinese-ium or Grizzly with are a bit expensive for what I'm guessing is also Chinese.
Any links would be very appreciated as word of mouth is the best way of sourcing good products...
 
An ebay seller: carbidetoolco. sells 1/2" stub refurbished carbide end mills, $6.83. I have some and they are excellent.American made, leave a great finish.
 
As a novice, the first thing you should learn about is feeds and speeds. There are plenty of formulas and programs available on the web, and free slide rule types can often be had free from the bigger makers of tooling. Actually, in the real world, I have this simple speed formula in my head (with sample equations:)

(Surface feet per minute) (times 4)
______________________________________ = Spindle RPM
(cutter diameter in inches)


1018 steel at 90 sfpm X 4
____________________________ = 720 RPM
1/2" end mill


6061-t6 aluminum at 400 sfpm X 4
______________________________________ = 6400 rpm
1/4" end mill


None of this is critical (but it does matter!), and other factors enter into the equation as well, so those numbers, or somewhat slower, might be a starting point on my knee mill. As far as feed rate goes, there are formulas out there you can use, which usually are giving tool movement per tooth based on material, cutting tool, and tooth count (and outputting feed per tooth.) You can also simply make the tool work hard enough to cut real chips, no crumbs or powder, but at the same time not hard enough that the machine and tool complain too much. Abusing cutters dulls them and breaks them. Start with known common machining metals instead of mystery metals, nothing at all exotic, make sure that all axes are locked except for the one you are using, make sure the setup is rigid, and cut some metal!

You will find that going by the book does not always achieve optimum results. Learn what you are looking for, and know what you should adjust and in which direction to improve the cut and make the tool and machine happy. You will dull and break some end mills along the way, even pros do it, but it will just be worse if you use cheap or dull used tools. The good ones, in good condition, and run under the correct conditions, will make you look like a pro. Use some of each while you are learning. We learn on the machine by experience, though some useful study and a good mentor is a BIG help, especially at first.
 
Trip said:
Search ebay for resharpened end mills . some really good deals can be had .
Click to expand...
pacifica said:
An ebay seller: carbidetoolco. sells 1/2" stub refurbished carbide end mills, $6.83. I have some and they are excellent.American made, leave a great finish.
Click to expand...
That is a really good price for carbide end mills, but I recommend that the OP starts out with standard high speed steel tooling, and learn how to work with it first. Not pushed too hard, and on softer materials, HSS is less demanding of proper technique,
 
I would suggest using Bob's formula to make up a chart of the speeds of your machine vs sizes from .25 to 3 inches to give the sfm.
list the target sfm for various materials below and you have an easy reference at the mill.
If you have to err, go for a little less sfm rather than too high. Your tools will last much longer.
Best of luck.
 
Bob Korves said:
That is a really good price for carbide end mills, but I recommend that the OP starts out with standard high speed steel tooling, and learn how to work with it first. Not pushed too hard, and on softer materials, HSS is less demanding of proper technique,
Click to expand...
With my machine topping out at 1700 rpm...I'm not sure Carbide tools are a good option for me?
I have been browsing ebay, though I'm uncomfortable with purchasing there. It is so hard to know where the tool is from or what kind of resharpening job they have done. I'd really like to have a decent set of new, but do I need to spend 70 to $100/ea to get a decent tool. I have no idea!
 
Last edited:
I've found many opportunities to buy multiples of small HHS and carbide end mills on Ebay. The last, five 3/8 solid carbide, 6 flute double end mills for about $5.00 ea.
This was a couple of months ago, they're still out there.
 
The type of mill you select is not only dependent on the speed you intend to cut, but also dependent on the material you intend to cut. Personally I prefer HHS mills for the bulk of the work I do. In total I have in the neighborhood of 1,000 different end mills with the vast majority being HSS. I would guess there are less than 50 carbide mills in the lot.

Most of my mills were acquired through equipment dealers, flea markets, and eBay. I did buy a number from Enco, but those were specialty mills for specific jobs. I do wish they were still around, because their prices for name brand mills were considerably less than most other vendors. I have found over the years that eBay lots can be a bargain if you're willing to look at lots of 25 pieces and larger. I have bought lots as large as 50 and more. When buying in larger numbers unit prices are generally considerably less expensive.

If I don't want to bother with sharpening them I usually inspect the pictures religiously. If I see anything the seller may have missed I ask questions. I usually only look at "Buy It Now Lots" that accept "best offers". From time to time I have purchased known damaged end mills that still can be sharpened. For those I would guess I've paid in the neighborhood of $2.00 per unit on sizes 1/2" to 1 1/2". For sizes 3/8" and under I try to buy "New" or "New Other". I find the smaller sizes more of a PIA to sharpen, especially when the prices for new, name brand quality ones are reasonably priced.
 
You must log in or register to reply here.
Back
Top