Wednesday, August 29, 2012

Our Philosophy on End Mills: Geometry

Take a close look at our end mills... under a microscope. What you will find is that they look much different than most all of our competitors. 

Edge Strength
Edge Strength: Eccentric relief between primary & secondary
There are numerous variables that have an impact of cutting tool performance and tool life. We designed the tools to be used in different conditions and different machines. We spent many years perfecting the length of the primary and secondary grind in combination with the eccentric relief on our tools. The Red arrow shows the direction of typical cutting tool forces. We’ve believe that we've engineered more edge strength into our tools than any other competitor on the market which means that you can run at higher chip loads.
Double Variable Helix
Double Variable Helix
Chatter has been a persistent problem in milling for many years. Typically most shops will reduce the RPM and/or Feed to reduce the amount of chatter. Chatter is a result of natural harmonics built within the tool which is operating at it's own natural frequency.  Because traditional end mills maintained a consistent helix angle along the length of the flute, the tools tended to get in "tune". Technically, called a Frequency Response Function (FRF).  

Unequal Flute Spacing on a Raptor 3/6
The Double Variable Helix design corrects for this problem with a number of  design elements which enable out tools to run at higher RPM chatter free:
  • Variable Flute Spacing - Each flute is unequally spaced around the circumference of the end mill, creating an out-of-phase cutting action.
  • Double Variable Helix - DVH - The helix angle changes along the cutting edge which further creates an out-of-phase cutting action. 

Heat kills
With the exception of hard milling, it's pretty common knowledge that the heat should be removed with the chip and the less heat transferred to the tool the longer the tool life.  

We've taken a look at that very carefully and have designed our tools to form chips a bit differently.  Chips are formed in the outer rake face of the tools. Instead of the chip traveling all the way down into the gullet of the tools, which causes a lot of friction and heat, and then 6' & 9' formed against the core diameter, we have designed our tools to take a much heavier chip load that most competitors. 

By taking a heavier chip load the material is forced to turn on itself in the other rake face and eject from the cut without traveling down the entire length of the rake face. Think of it like throwing a tennis ball to a point 10 feet in front of you vs throwing it directly between your feet.

Friday, August 24, 2012

Our Philosophy on End Mills: Carbide Substrate

The most commonly used term for carbide is “Micro-Grain” but it does NOT really describe the differences that have evolved since the first development of “Micro-Grain” in the past 40-50 years. Fine, Ultra-Fine and Sub Micron grains are some of the current terminology that is used.

Two other commonly used terms are “toughness” and “wear resistance.” We’ve found that neither term can be used as a proper gage. Here’s why:
  • Toughness - Fracture toughness is not only a characteristic of the material but also a function of the loading conditions. Carbide rod is measured for "toughness” before geometry has been ground into the tool and a finished, ground tool can vary as much as 300% in “fracture toughness” based upon geometry alone.
  • Wear Resistance - Cutting tool wear is a result of complicated physical, chemical, and thermo-mechanical actions. Tool wear is caused by such mechanisms as adhesion, abrasion, diffusion & oxidation that all act together with predominant influence of one or more of them in different situations within the CNC machine, which is quite different from lab testing.

Cemented Carbide is similar to cement in more than name only. Cobalt is the “lime” that holds the Carbide “gravel” together. If a large chunk of carbide is exposed at the cutting edge it will fracture off just like a piece of gravel on a cement walkway edge. 
Destiny Tool Substrates compared to our competitors

Bottom Line: At Destiny Tool, through over a decade of testing, we have selected substrates that work together with our tools for optimal tool life and performance in specific materials. Our substrates range from a transverse rupture strength of 580,000 - 630,000 psi and vary in cobalt content from 10 -12% based upon the specific application that the tool was designed. You can trust that we’ve selected the correct substrate for your application material.

Tuesday, August 21, 2012

Manufacturer's Agents wanted!

We're preparing for the IMTS 2012 event and hoping to meet Manufacturer's Reps for much of the North American Market area. 

If you are a rep with cutting tool experience please plan on stopping by our IMTS booth W-2232 during the show so we can meet you and show you a little bit about our product offering. 

Our Manufacturer's representatives often assume the role of CNC Machining application consultants, offering wholesale, government and machine shop customers the best tooling recommendations from among our product offering.


  • No "Direct" to end-user sales
  • Calling on Industrial Distributors accounts 
  • Calling on Machine Tool Dealers and OEM's in their market area.
  • Providing Technical support at End User accounts

Our independent agents typically make sales presentations and solve application problems for end users, industrial cutting tool distributors, machine tool dealers and, in some instances, Machine Tool Builders. 

Agents are expected to be able to demonstrate product samples, answer the client's questions, then make recommendations on which products best fit their client's needs.

A technical understanding and use and function of Surface Footage & Chip Load is required. Agents should have a working knowledge of coatings, ISO materials classification, competitive products lines and competitive distribution channels in their market area.

We are actively seeking agents with affiliated product lines that work in CNC milling machines such as rotary toolholders, work holding and no competitive cutting tool product lines.

Our products are targeted to specific material niches which include machining Aluminum and non ferrous alloys, Stainless Steels, Hi temperature alloys such as Titanium, Inconel, Kovar, Monel and other exotics.  Our target markets are aerospace, defense, performance automotive, wind, solar, and medical market segments.

Prospective agents should have a working knowledge of manufacturing facilities in their market area and who services them at the industrial distributor level. We are actively looking for industrial distributor partners to act as regional stocking distributors in a number of markets. Agents are expected to develop targeted industrial distributors to fulfill this role in their market area.

Our Philosophy on End Mills: Introduction

At Destiny Tool we believe that and end mill is only as good as the engineering that is behind it.  We’ve cut our teeth in non-ferrous and hi-temp alloys for many years and we believe that our performance end mills are the very best available int the global market for those specific material groups.  In our view, there are four major components that make up a performance end mill:
  • Substrate
  • Geometry
  • Tolerance
  • Coating
In the next few weeks we'll be detailing out each of these to help you better understand how to apply our end mills in your CNC milling machines. Stay Tuned for more information!