ROYAL CNC I.D. WORKHOLDING
For Turning Applications

I.D. Workholding Advantages:

  • Allows for full access to the entire length of the workpiece so all external diameters can be turned in a single operation, guaranteeing perfect concentricity.
  • On sub-spindle machines, I.D. gripping on the second spindle eliminates the risk of surface damage that can be caused by second-op O.D. gripping of a previously-turned diameter.
  • For many parts, the engagement-length of an I.D. bore can be greater than what is available for O.D. gripping, resulting in superior rigidity and torque transmission.
  • I.D. systems tend to be more streamlined than O.D. systems, enabling better part access – especially important for use on machines with live tooling.

Bolt & Go™

Royal’s exclusive Bolt & Go™ mounting feature ensures maximum accuracy and rigidity with no adjusting required. Other systems require the mandrel to be trammed in – a hassle that wastes valuable machining time.

Oversized Flange

Borrowing from the winning design of our CNC Collet Chucks, all bodies feature an oversized flange to protect the machine tool spindle bearings from coolant penetration.

Z-Axis Repeatability

Pullback action draws the workpiece securely against a ground locating plate for maximum “dual-contact” rigidity and consistent z-axis repeatability.

Easy Installation

Royal CNC I.D. Workholding Systems include all mounting hardware, wrenches, and a custom-machined drawtube connector to ensure hassle-free installation.

Heavy-Duty Construction

Royal consistently builds products that outlast the competition, especially in the most demanding environments. Bodies, mandrels, and expanding rods are all hardened to Rc 61-63 for maximum durability.

Same-Day Shipping

Royal maintains a huge inventory of standard bodies, mandrels, and sleeves to help us achieve our goal of same-day shipping on all orders.
CNC Expanding Mandrel 3D Model

Custom Systems

If our standard line doesn’t meet your needs, give us a call to discuss your special requirements. Capabilities include:

  • Larger sizes – up to 25″ diameter
  • Extended-length systems
  • Multi-step systems for locating on multiple bore diameters
  • Automation enhancements such as ejector rings, part confirmation, etc.

Ultra-Precision Accuracy

System runout guaranteed to be 0.0005″ TIR or better.

Modular Design

Mandrel models A-E all have a common mounting interface with the body so the system can grow with your needs.

Wide Gripping Range

A broad 0.032″ expansion range (0.020″ for model A) enables many bore sizes to be covered with a single expanding sleeve.

Parallel-Grip

Royal’s double-angle design provides parallel sleeve expansion, ensuring full-length part contact and positive release when the part is unclamped.

Outstanding Tool Clearance

Royal CNC I.D. Workholding Systems have been optimized for superior tool clearance over other workholding systems.

Completely Sealed

All expanding sleeve slots are sealed to prevent contaminants from accumulating on the mandrel surface – ensuring years of trouble-free service. An internal O-ring on the drawtube connector offers additional protection.

How to Order:

  1. Choose the appropriate body assembly based upon your application.
  2. Choose the appropriate mandrel (models A-E) based upon the diameter you need to All mandrels and bodies share a common mounting interface for full interchangeability.
  3. If required, choose the appropriate part locator to provide a ground banking surface for the workpiece.
  4. Choose the appropriate expanding sleeve based upon the mandrel and diameter you need to grip.

Step 1 – Choose Body Assembly

CNC BODY – For CNC Lathes

Proudly Made In USA
Mandrel Sizing Chart
  • This body provides a precision interface for mounting the system to a CNC lathe spindle.
  • CNC body assembly incudes the hardened steel body, a custom-machined drawtube connector for hassle-free installation, and all mounting hardware.
  • Order mandrels, locators, and sleeves separately.

Dimensions

Note - dimension shown without optional part locator

SPINDLE
MOUNT
A B C D E F G
A2-5 3.75 4.34 See
Mandrel
Chart 
6.45 5.00
A2-6 4.00 4.59 7.45 6.25
140mm 3.90 4.49 7.45 6.25
A2-8 5.00 5.59 9.45 8.00

Royal CNC I.D. Body Assemblies

Filters Sort results
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Spindle Type*
PART
NUMBER
PRICE
140MM
$2,060
A2-5
$1,590
A2-6
$1,930
A2-8
$2,590

Step 2 - Choose Mandrel

  • Choose appropriate mandrel model according to gripping range.
  • All Royal mandrels have a common precision ground interface for complete compatibility with all Royal I.D. body assemblies.
  • Order body assembly, locators, and sleeves separately.

Royal Mandrels

Filters Sort results
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Mandrel
Model
Gripping
Range
C
D
E
PART NUMBER
PRICE
A
0.479–0.640
1.57
0.57
0.87
47100
$1,565
B
0.620 –0.901
1.81
0.59
1.06
47101
$1,565
C
0.870 –1.151
2.05
0.61
1.26
47102
$1,565
D
1.120 –1.651
2.32
0.60
1.50
47103
$1,565
E
1.620 –3.276
2.52
0.58
1.69
47104
$1,565

Step 3 - Choose Part Locator

  • Optional part locator bolts to the front of the mandrel and provides a precision banking surface for the workpiece to locate against.
  • Order body assembly, mandrels, and sleeves separately.

Royal Part Locators

Filters Sort results
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Fits
Mandrel
Model
Width
Outer
Diameter
Part
Number
PRICE
A
0.47
1.57
$312
B
0.47
1.57
$312
C
0.47
2.95
$360
D
0.47
2.95
$360
E
0.47
2.95
$360

Step 4 - Choose Expanding Sleeve

  • Order expanding sleeves according to mandrel models A thru E.
  • All expanding sleeves are fully sealed against coolant and chip penetration.
  • Parallel grip ensures full-length part contact for optimum accuracy and grip force.
  • All sleeves collapse 0.005" below nominal ground size to ensure easy part loading and unloading.
  • Order body assembly, mandrels, and locators separately

Royal Expanding Sleeves - Model A

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Nominal Sleeve
Diameter
Gripping
Range
Part
Number
PRICE
31⁄64″
0.479 - 0.499
47120
*
Not sealed due to limited wall thickness.
$435
1⁄2″
0.495 - 0.515
47121
*
Not sealed due to limited wall thickness.
$435
33⁄64″
0.511 - 0.531
$435
17⁄32″
0.526 - 0.546
$435
35⁄64″
0.542 - 0.562
$435
9⁄16″
0.558 - 0.578
$435
37⁄64″
0.573 - 0.593
$435
19⁄32″
0.589 - 0.609
$435
39⁄64″
0.604 - 0.624
$435
5⁄8″
0.620 - 0.640
$435
41⁄64″
0.636 - 0.656
$435

Royal Expanding Sleeves - Model B

Filters Sort results
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Nominal Sleeve
Diameter
Gripping
Range
Part
Number
PRICE
5⁄8″
0.620 - 0.651
47130
*
Not sealed due to limited wall thickness.
$481
21⁄32″
0.651 - 0.682
$481
11⁄16″
0.683 - 0.714
$481
23⁄32″
0.714 - 0.745
$481
3⁄4″
0.745 - 0.776
$481
25⁄32″
0.776 - 0.807
$481
13⁄16″
0.808 - 0.839
$481
27⁄32″
0.830 - 0.870
$481
7⁄8″
0.870 - 0.901
$481

Royal Expanding Sleeves - Model C

Filters Sort results
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Nominal Sleeve
Diameter
Gripping
Range
Part
Number
PRICE
7⁄8″
0.870 - 0.901
$481
29⁄32″
0.901 - 0.932
$481
15⁄16″
0.933 - 0.964
$481
31⁄32″
0.964 - 0.995
$481
1″
0.995 - 1.026
$481
1 1⁄32″
1.026 - 1.057
$481
1 1⁄16″
1.058 - 1.089
$481
1 3⁄32″
1.089 - 1.120
$481
1 1⁄8″
1.120 - 1.151
$481

Royal Expanding Sleeves - Model D

Filters Sort results
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Nominal Sleeve
Diameter
Gripping
Range
Part
Number
PRICE
1 1⁄8″
1.120 - 1.151
$517
1 5⁄32″
1.151 - 1.182
$517
1 3⁄16″
1.183 - 1.214
$517
1 7⁄32″
1.214 - 1.245
$517
1 1⁄4″
1.145 - 1.276
$517
1 9⁄32″
1.276 - 1.317
$517
1 5⁄16″
1.308 - 1.339
$517
1 11⁄32″
1.339 - 1.370
$517
1 3⁄8″
1.370 - 1.401
$517
1 13⁄32″
1.401 - 1.432
$517
1 7⁄16″
1.433 - 1.464
$517
1 15⁄32″
1.464 - 1.495
$517
1 1⁄2″
1.495 - 1.526
$517
1 17⁄32″
1.526 - 1.557
$517
1 9⁄16″
1.558 - 1.589
$517
1 19⁄32″
1.589 - 1.620
$517
1 5⁄8″
1.620 - 1.651
$517

Royal Expanding Sleeves - Model E

Filters Sort results
Reset Apply
Nominal Sleeve
Diameter
Gripping
Range
Part
Number
PRICE
1 5⁄8″
1.620 - 1.651
$630
1 21⁄32″
1.651 - 1.682
$630
1 11⁄16″
1.683 - 1.714
$630
1 23⁄32″
1.714 - 1.745
$630
1 3⁄4″
1.745 - 1.776
$630
1 25⁄32″
1.776 - 1.807
$630
1 13⁄16″
1.808 - 1.839
$630
1 27⁄32″
1.839 - 1.870
$630
1 7⁄8″
1.870 - 1.901
$630
1 29⁄32″
1.901 - 1.932
$630
1 15⁄16″
1.933 - 1.964
$630
1 31⁄32″
1.964 - 1.995
$630
2″
1.995 - 2.026
$630
2 1⁄32″
2.026 - 2.057
$630
2 1⁄16″
2.058 - 2.089
$630
2 3⁄32″
2.089 - 2.120
$630
2 1⁄8″
2.120 - 2.151
$630
2 5⁄32″
2.151 - 2.182
$630
2 3⁄16″
2.183 - 2.214
$630
2 7⁄32″
2.214 - 2.245
$630
2 1⁄4″
2.245 - 2.276
$630
2 9⁄32″
2.276 - 2.307
$630
2 5⁄16″
2.308 - 2.339
$630
2 11⁄32″
2.339 - 2.370
$630
2 3⁄8″
2.370 - 2.401
$630
2 13⁄32″
2.401 - 2.432
$630
2 7⁄16″
2.433 - 2.464
$630
2 15⁄32″
2.464 - 2.495
$630
2 1⁄2″
2.495 - 2.526
$630
2 17⁄32″
2.526 - 2.557
$714
2 9⁄16″
2.558 - 2.589
$714
2 19⁄32″
2.589 - 2.620
$714
2 5⁄8″
2.620 - 2.651
$714
2 21⁄32″
2.651 - 2.682
$714
2 11⁄16″
2.683 - 2.714
$714
2 23⁄32″
2.714 - 2.745
$714
2 3⁄4″
2.745 - 2.776
$714
2 25⁄32″
2.776 - 2.807
$714
2 13⁄16″
2.808 - 2.839
$714
2 27⁄32″
2.839 - 2.870
$714
2 7⁄8″
2.870 - 2.901
$714
2 29⁄32″
2.901 - 2.932
$714
2 15⁄16″
2.933 - 2.964
$714
2 31⁄32″
2.964 - 2.995
$714
3″
2.995 - 3.026
$714
3 1⁄32″
3.026 - 3.057
$714
3 1⁄16″
3.058 - 3.089
$714
3 3⁄32″
3.089 - 3.120
$714
3 1⁄8″
3.120 - 3.151
$714
3 5⁄32″
3.151 - 3.182
$714
3 7⁄32″
3.214 - 3.245
$714
3 3⁄16″
3.183 - 3.214
$714
3 1⁄4″
3.245 - 3.276
$714

*Not sealed due to limited wall thickness.
Note – sleeves larger than 2-1/2" dia. are 0.28" longer than dimension E and terminate flush with the face of the expanding rod.