NEXT GENERATION TOOLING
  • Home
    • Schedule
    • Training
  • About
    • History
    • Contact
  • Territories
    • NorCal & N-NV
    • SoCal & S-NV
    • Mountains
  • Principals
    • Tooling >
      • 2V Industries
      • BIG Daishowa
      • Champion Storage
      • Drill America
      • Jewell Group
      • Mapal
      • Martindale Gaylee
      • OSG Tool
      • Performance Micro Tool
      • Platinum Tooling
      • TechniksUSA
    • Workholding >
      • BIG Daishowa
      • Earth Chain
      • Jergens
      • mPower Workholding
  • Promotions
  • Events
  • News
  • Technical

The BIG-PLUS Difference

1/22/2020

0 Comments

 
The Big Plus Difference
Spindles and tool holders are in a constant battle with the forces of nature, with this battle becoming more and more difficult with heavier cuts and longer projections. Chattering and deflection have always been the bane of machinists’ existence, so much so that the sight of a long and slender toolholder will immediately cause goosebumps.

If you understand why a long tool holder behaves the way it does, you’ll know that there are ways to fight back against this bending. Every machinist knows that short and stubby holders are more resistant to deflection than long and slender holders. You’ve also probably heard that, if possible, you’ll want most of your cutting forces to be axial rather than radial.

Not only does this fight chatter in operations like boring, but your spindle also is better equipped to handle loads in this axis. However, these options aren’t always going to be on the table, especially in unavoidable long-reach situations and many milling operations.

In this constant battle with tool deflection, much time and effort has been spent designing shorter holders, stiffer tools, and clever anti-vibration geometry and materials. But oftentimes, the body diameter(s) of the holder can be overlooked as a means of increasing rigidity, especially in situations where it is all you have to work with. This is a serious shame, as you’ll soon discover.

The concept of dual-contact technology has been around for years, existing in many different forms but always with the same goal of capitalizing on this untapped potential of rigidity. For those who don’t know, dual contact refers to the shank contacting the spindle taper and the spindle face simultaneously.

Oftentimes, the solution involved ex post facto alterations to the spindle or tool holder, such as using ground spacers or shims to close the gap, for example. In other words, there was no standard solution, and if you wanted dual contact, you would have to be prepared to spend time and money either buying modified tool holders or modifying them yourself to adapt them to your spindle.

BIG-PLUS emerged as a solution to this issue. Essentially, both the spindle and tool holder were ground to precise specifications so that they closed the gap between spindle face and flange in unison (while depending on very small elastic deformation in the spindle). What this meant is that operators were able to confidently switch BIG-PLUS tooling in and out of a BIG-PLUS spindle and achieve guaranteed dual contact.

Not only that, but standard tooling could still be used in a BIG-PLUS spindle if necessary, and vice versa.

Though not technically an international standard, it’s been adopted by many machine tool builders because of the clear performance improvements and simplicity. In fact, BIG-PLUS spindles come standard on more machines than you would think. We often come across operators that have machines with BIG-PLUS spindles and don’t even realize it.
big-plus flange vs conventional toolholder engagement
How exactly does dual contact help with tool rigidity? The torque (or moment) exerted by the cutting forces is maximized at the point where the holder and spindle meet, the base of the tool holder. With standard CAT40 tool holders, this would be the gage line diameter. When the holder contacts the spindle face via BIG-PLUS, the effective diameter would be the larger diameter of the v-flange, since this is the new anchoring point of the holder and spindle. So, you are beefing up the diameter at the point where the reactionary force is greatest.

It’s not too much of a leap to conclude that a larger effective diameter will give you more rigidity. That being said, you may still be asking yourself: does such a seemingly small increase in diameter really make a difference? To understand the effect of BIG-PLUS, you must understand the physics behind it.

Imagine a simple scenario in which a tool holder is represented by a cylindrical bar that is fixed at one end and free-floating at the other. In other words, a cantilever beam. If you think about it, this is essentially what a tool holder becomes once it’s secure in the spindle. Now, let’s introduce a radial force F that acts downward at the suspended end of the bar, which represents a cutting force you would encounter when milling or boring, for example. The bar, as you might expect, will want to bend downward. It’s similar to how a diving board bends when someone stands at the end, though less exaggerated.
Big Plus deflection drawing
It’s possible to predict the amount of deflection (or inversely, bending stiffness) at the end of this hypothetical bar if you know its length, diameter and material. The expression below represents the stiffness k at the end of the bar where d=diameter, L=Length and E=Modulus of Elasticity
(this depends on the bar material). The greater the value of k, the stiffer (or more rigid) our bar will be.
Picture
I won’t ask you to do any math here, I just want you to look at the equation. We can see that increasing d will increase the value of k, while increasing L will decrease the value of k, since it’s in the denominator of the equation. This certainly makes sense if you think about it: a short and squat bar (large d, small L) will be more rigid than a long and slender bar (small d, large L). 

Something interesting to note is that d is raised to the 4th power, while L is only raised to the 3rd power. Diameter affects rigidity an entire order of magnitude more than the length does. This is where the power of BIG-PLUS comes from and is why a small increase in diameter can have such a powerful effect on performance.
Big Plus Strict gage control surface finish
For a CAT40 tool holder, the gage line diameter is Ø44.45 mm and the flange diameter is Ø63.5 mm. Let’s imagine two bars of identical length and material, so L and E remain unchanged. One bar has a diameter of Ø44.45 mm (standard CAT40) and the other has Ø63.5 mm (BIG-PLUS CAT40).

If you were to plug these values into the above equation for comparison, you would find that the BIG-PLUS holder results in a k value that is around 4 times greater than the standard bar. Based on this comparison, you could say that a BIG-PLUS holder is 4 times as rigid as an identical standard CAT40 holder, because it is 4 times as resistant to deflection.

Think of the tool life and surface finish improvements you would see with a tool that is 4 times more rigid, not to mention the reduction in fretting and potential for reduced cycle time. You would get similar results if you were to make the same comparison for CAT50, BT40, BT30, etc.

Big Plus Comparison of Deflection Chart
If you’re still not convinced, we can also compare the rigidity in this way: Let’s say there is a Ø63.5 mm BIG-PLUS CAT40 bar of some arbitrary length. One of our more common gage lengths is 105 mm, or just over 4 inches, so let’s use it as an example. 

You’re probably wondering, at what length would a comparable standard CAT40 holder have an equal stiffness? If we take our stiffness expression and set it equal to itself (one side representing BIG-PLUS, the other non BIG-PLUS), we can plug in this BIG-PLUS holder length and our known diameters to find our unknown non-BIG PLUS length:
Big Plus Stiffness Formula
What does this mean? A BIG-PLUS holder of around 4 inches or 105 mm in length will have equal rigidity to a standard CAT40 holder of around 2.5 inches or 65 mm in length. Any experienced machinist will know quite well the difference in rigidity between a 4-inch long holder and a 2.5-inch long holder.

If this is true, we can say that implementing BIG-PLUS is equivalent to a 40% reduction in length in terms of rigidity. Theoretically, a BIG-PLUS tool holder will behave like a standard tool holder that is nearly half of its length! 

Obviously, we’ve used simple and idealized cases here to represent the complicated and dynamic world of metal cutting. Tool holders, of course, don’t have uniform body diameters or materials and the cutting forces usually aren’t acting in one direction in a constant and predictable way. If our holder necks up and down to different body diameters along its length, which is realistically what happens, each of these sections would be its own microcosm of “beam” that would influence the overall behavior (at that point, finite element analysis on a computer becomes the only practical way to predict behavior). 

So, will the advantage of BIG-PLUS really be as dramatic as our hand-calculated classical beam theory suggests? Probably not, but it depends on the tool holder/tool. Most cases will follow our simple model quite closely in practice; others not so much. If nothing else, we’ve demonstrated how dramatically the flange contact of BIG-PLUS can influence rigidity, at least in a purely mathematical sense. 

As if you needed any more reasons to be on the BIG-PLUS bandwagon besides increased rigidity, you will also eliminate Z-axis movement at high speeds, improve ATC repeatability and decrease fretting. This means that you will take heavier cuts, scrap less parts, and increase tool and spindle life.
BIG-PLUS isn’t a new idea by any means, but with a proven track record of tackling tough jobs, it’s hard to imagine working in a modern machine shop and not taking advantage of what it has to offer.

If you’re still not convinced, we can also compare the rigidity in this way: Let’s say there is a Ø63.5 mm BIG-PLUS CAT40 bar of some arbitrary length. One of our more common gage lengths is 105 mm, or just over 4 inches, so let’s use it as an example. 

You’re probably wondering, at what length would a comparable standard CAT40 holder have an equal stiffness? If we take our stiffness expression and set it equal to itself (one side representing BIG-PLUS, the other non BIG-PLUS), we can plug in this BIG-PLUS holder length and our known diameters to find our unknown non-BIG PLUS length:
0 Comments

    Technical Support Blog

    At Next Generation Tool we often run into many of the same technical questions from different customers. This section should answer many of your most common questions.

    We set up this special blog for the most commonly asked questions and machinist data tables for your easy reference.

    If you've got a question that's not answered here, then just send us a quick note via email or reach one of us on our CONTACTS page here on the website
    email us

    Authorship

    Our technical section is written by several different people. Sometimes, it's from our team here at Next Generation Tooling & at other times it's by one of the innovative manufacturer's we represent in California and Nevada.

    Archives

    March 2023
    February 2023
    January 2023
    December 2022
    November 2022
    October 2022
    September 2022
    August 2022
    July 2022
    June 2022
    May 2022
    April 2022
    March 2022
    February 2022
    December 2021
    November 2021
    October 2021
    September 2021
    August 2021
    July 2021
    June 2021
    May 2021
    April 2021
    March 2021
    February 2021
    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    March 2020
    February 2020
    January 2020
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    March 2019
    January 2019
    September 2018
    June 2018
    April 2018
    February 2018
    December 2017
    November 2017
    October 2017
    August 2017
    June 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    August 2016
    March 2016
    February 2016
    January 2016
    November 2015
    August 2015
    July 2015
    May 2015
    April 2015
    March 2015
    November 2014
    August 2014
    July 2014
    December 2013
    November 2013
    September 2013
    July 2013
    March 2013
    December 2012
    March 2012
    November 2011
    May 2011
    March 2011
    January 2011
    December 2010
    November 2010
    October 2010

    Categories

    All
    5th Axis
    Aerospace
    Allied Machine
    Aluminum Oxide
    Angle Head
    AT3
    Balance
    Bellmouthed Hole
    Big Daishowa
    Big EWA Automatic Boring
    Big Kaiser
    BIG Plus
    Blue Photon
    Bone Screws
    Boring Tool
    Carbide
    Carmex Precision
    CBN
    Centerline Deviation
    Ceramic Black
    Ceramic End Mill
    Ceramic Inserts
    Ceramic Oxide
    Ceramic Whiskered
    Ceramic White
    Chamfer
    Champion Tool Storage
    Chip Breaking
    Circular Saw
    Class Of Fit
    CNC Lathe Tooling
    Collet
    Collet Chuck
    Collet ER
    Composites
    Covid-19
    Deep Hole Boring
    Deep Hole Drilling
    Drilling
    Dual Contact
    Dyna Contact Gage
    Dyna Force Tool
    Dyna Test Bar
    EMO
    End Mill
    Exotap
    Facemill
    Fixturing
    Fretting
    Gaylee Saw
    Hard Turning
    Heimatec
    Helical Interpolation
    Hohl Shaft Kegel
    How Its Made
    HSK A
    HSK-A
    HSK E
    HSK-E
    HSK F
    HSK-F
    HXL Tap
    Hy Pro Tap
    Hy-Pro Tap
    IMTS
    Jergens
    Kurt
    Lang
    Live Tooling
    MA Ford
    Maintenance Cart
    Mapal
    Martindale Saw
    Material: Aluminum
    Material: CFRP
    Material: D2
    Material: Hastelloy
    Material: Inconel
    Material: Peek
    Material: Stone
    Material Titanium
    Material: VC-10
    Metric Course Thread
    Metric Fine Thread
    Metric Thread Chart
    Microconic
    Micromachining
    ModLoc
    Modular
    Mogul Bars
    MPower
    No Go Too Loose
    NTK
    NTK HX5
    On Site Training
    OptiMill-SPM
    OSG Tap & Die
    Oversized Thread
    Parlec
    PCD
    PCT Firm Hold
    Platinum Tooling
    Projection Length
    Pull Studs
    Reamer
    Retention Knob
    Rotary Toolholders
    Rotary Toolholders BT
    Rotary Toolholders CAT
    Rotary Toolholders HSK
    Rotary Toolholders Hydraulic
    Rotary Toolholders Shrink
    Rough Thread
    Runout
    Runout Axial
    Runout Radial
    Saw Selection
    Short Tap Life
    Sialons
    Silicon Nitride
    Smart Damper
    Speed Increaser
    SpeedLoc
    Speroni STP Essntia
    Spindle Mouth Wear
    Swiss
    Swiss Machining
    Taper Wear
    Tapping Feed
    Tapping; Form
    Tapping IPM
    Tapping: Roll
    Tapping RPM
    Tapping Speed
    Tap Tolerance
    Technical Training
    Technicrafts
    Techniks USA
    Thread Milling
    Thread Whirling
    T.I.R.
    Tolerance
    Toolchanger Alignment
    Toolholder Taper
    Tool Presetter
    Torn Thread
    Troubleshooting
    UNC Thread Size
    Undersized Thread
    UNF Thread Size
    Unilock
    Vises
    Workholding

    RSS Feed

Picture

About
Contact
TOOLING
WORKHOLDING
EVENTS
NEWS
TECHNICAL


Established 1995
​

Next Generation Tooling
10240 Cavalletti Drive
Sacramento CA 95829
916.765.4227
Northern California
23 Maxwell Street
Suite B
Lodi, CA 95240
Southern California
22343 La Palma Avenue
​Suite 126
Yorba Linda, CA 92887
© 2023 Next Generation Tooling, LLC. 
All Rights Reserved
Created by Rapid Production Marketing

Find us on Instagram @nextgentool

  • Home
    • Schedule
    • Training
  • About
    • History
    • Contact
  • Territories
    • NorCal & N-NV
    • SoCal & S-NV
    • Mountains
  • Principals
    • Tooling >
      • 2V Industries
      • BIG Daishowa
      • Champion Storage
      • Drill America
      • Jewell Group
      • Mapal
      • Martindale Gaylee
      • OSG Tool
      • Performance Micro Tool
      • Platinum Tooling
      • TechniksUSA
    • Workholding >
      • BIG Daishowa
      • Earth Chain
      • Jergens
      • mPower Workholding
  • Promotions
  • Events
  • News
  • Technical