Richon Tools order

[chucketn]

???
I received my large order of end mills from Richon Tools today. I purchased pairs of cutters, from 1/16” to 5/8”, 2 and 4 flute, and some metric ball end mills. They came in individual plastic tubes, wrapped in a plastic bag, inside a very tough plastic outer bag.
I opened a few for a look. I was surprised to find several had what appear to be chips in the end cutting edge. At first I thought they were just the profile where the flutes met the cutting edge, but not all of them have this chip. Is this normal? I really don’t want to use them if they are damaged/defective.
Also, to preclude abuse of my new tools, does anyone have or know of a spreadsheet for determining feeds and speeds based on mill cutter diameter? Is there a simple formula that I can put into Excel that would give me a starting RPM, based on cutter diameter and material such as steel, aluminum, or brass?

Chuck in E. TN

 

[portlandron]

Some end mills have a small area removed on the cutting edge of the end cutter. I would say if the "chip" is the same size and in the same place on each flute then that's the way they were made.

 

[chucketn]

That's just it, not all the cutting surfaces, even on the same cutter, have them.
I'll try to figure out how to draw a picture, or post photos.

Chuck in E. TN

 

[Tin Falcon]

http://littlemachineshop.com/Reference/CuttingSpeeds.php#Milling

Speed(RPM)= 12 V
Pi D

12 converts feet to inches
V surface feet per minute cutting rate of material.
D Diameter of cutter

feed = (inches per tooth) x (number of teeth) x (Spindle rpm)

Vary the DOC(depth of cut based on machine size and power)

While you can make a spread sheet there are many charts already published like the machinery hand book
or just use a hand held calculator.
Tin

 

[rklopp]

You can figure out the speed in your head if you remember: 1" diameter at 400 RPM in mild steel with HSS cutters.

The speed for other diameters is inversely proportional, i.e., run a 1/2" cutter at 800 RPM and a 2" cutter at 200 RPM.

Double the speeds for aluminum, even triple or more for leaded brass (though it's not a necessity). Go 2/3 the speed in cast iron.

Double the speeds at the very least for carbide cutters. Thus, you can easily run a 1" diameter faster than 1600 RPM in aluminum with carbide.

These rules of thumb work for turning and milling. In turning, the relevant diameter is the workpiece diameter. In milling, it's the cutter diameter.

 

[chucketn]

After digesting the input here and on a couple of other forums, I have concluded that the Richon end mills are not chipped. There were, however, a few other problems with the order. I had ordered a pair of 10 mm ball Nose end mills and received a pair of straight 10 mm end mills, one extra ½” 2 Flute, and 2 extra 3/8” 4 Flutes and a substituted part # for the 3/16 4 flutes.
I emailed Peter at Richon to apologize for the misunderstanding of the “Chipped” cutting edges and point out the other errors.
Next step is to actually cut something! I will comment here as to cutting quality later, that is if this “Noob” can determine quality!
I also will work on building an Excel based feed and speed Ballpark Calculator that I can enter material and cutter diameter to get a conservative RPM setting.
Thanks to all that commented on this thread.
Chuck in E. TN

 

[Swede]

Chuck, it sounds like you are in the beginning stages of accumulating milling cutters. I don't know if you are an eBay guy or not, but there are some outstanding deals to be had on eBay, with one caveat - be sure the cutters are advertised as new, totally new, never used... you get the idea. I'd never buy used cutters on eBay, or even supposedly "sharpened" cutters.

The reason I like eBay so much for general purchases - you can buy brand new, name-brand cutters at ridiculous prices, cutters from companies like Sossner, Niagra, etc. And these really are (IMO) worth their premium over import cutters.

Big shops buy cutters by the case. We look at a pair of 1/2" carbide cutters like crown jewels. A big shop would buy 100 of them, use 83 for a contract, and then sell the rest as NOS (New Old Stock) to people like us!