TACO = T {Transparency}, A {Accountability}, C {Consistency}, O {Originality},
Revolving Die Heads DRSA [ CNC ]
External Threading Revolving Die Heads DRSA [ CNC ]
Solid Adjustable Circular Chaser Die-Heads: DRSA
📌 Purpose:
DRSA 4-Chaser Die head – Solid
Adjustable Circular Chaser Diehead
(Non-Opening Type for
Reversing Spindle Applications)
The Solid Adjustable Circular
Chaser Diehead is an ultra-light, non-opening threading solution designed
for use on machines with reversing spindles, such as rotary transfer
systems and CNC machining centers. It functions similarly to a rigid
tapping system, offering precision threading in compact, high-speed
environments.
The DRSA style diehead is
a robust 4-chaser threading tool designed for use on machines equipped with revolving
spindles. Engineered for durability and versatility, it is well-suited for
a wide range of threading applications.
🏗️ Machine Compatibility:
Model DRSA Die Heads can
be seamlessly mounted on:
v Centre
lathes
v Capstans
and turret lathes
v Semi-automatic
machines
v Drilling
machines and Milling machines
v Radial
drilling machines
v CNC,
VMC and HMC machines
v Rotary
transfer machines
v Multi-spindle
automatics with reversing spindles
v Applications
requiring rigid, accurate threading in confined or high-speed setups
🛠️ DRSA Die Head Technical Data
|
Diehead Model |
Threading Capacity (Metric) |
Threading Capacity (Inch) |
Suitable Chaser Set |
ØA |
B |
C |
ØD |
ØE |
Approx Weight (Kg.) |
|
DRSA 9/16” |
7 – 14 mm |
1/4” – 9/16” |
9/16” |
73.15 |
37.34 |
48.77 |
38.10 |
23.62 |
0.900 Kg. |
|
DRSA 13/16” |
7 – 14 mm |
1/4” – 9/16” |
13/16” |
92.20 |
41.40 |
51.56 |
38.10 |
23.62 |
3.000 Kg. |
|
DRSA 1” |
7 – 20 mm |
1/4” – 13/16” |
1” |
103.12 |
45.97 |
50.80 |
41.40 |
27.94 |
3.100 Kg. |
|
DRSA 1-1/16” |
10 – 25 mm |
3/8” – 1” |
1-1/16” |
98.55 |
41.40 |
52.07 |
41.40 |
27.94 |
3.200 Kg. |
|
DRSA 1-5/8” |
13 – 27 mm |
1/2” – 1-1/16” |
1-5/8” |
123.95 |
48.01 |
60.45 |
69.85 |
27.94 |
5.400 Kg. |
📝 Important Ordering Note: When placing an order for DRSA models,
please specify the required shank [ e.g., Straight Shank, Straight
Coolant] to ensure compatibility with your machine spindle. Additionally,
kindly purchase the appropriate chaser set based on the material you intend to
process. [ Special Shanks: Supplied on request at an additional cost,
depending on the availability of the required shank. ]
Engineered for reliability,
speed, and precision in high-performance threading operations.
🤖 Smart Function:
|
🧭
Function |
📖
Description |
🎯
Benefit |
|
🎯
Micrometric Diameter Adjustment |
Knurled screw with
engraved calibration lines |
Enables precise thread
sizing across production runs |
|
🔄 Circular
Chaser Technology |
Reduces rubbing and enhances
chip clearance |
Improves thread quality and
extends tool life |
|
🧰 Universal
Machine Fit |
Compatible with
lathes, drilling, milling, CNC, VMC, HMC machines |
Maximizes setup
flexibility across manual and automated systems |
|
🔁
Bidirectional Threading |
Supports both right-hand and
left-hand threads with dedicated chasers |
Expands threading capability for
diverse applications |
|
⚙️ High-Speed
Threading |
Operates efficiently
from 100–600 RPM |
Delivers accurate
threading at high speeds |
|
🛡️
Precision-Ground Components |
Rigid build with close-tolerance
parts |
Reduces vibration and enhances
surface finish |
|
🔧 Quick
Chaser Change |
Four-screw cover plate
for fast replacement |
Minimizes downtime and
simplifies maintenance |
|
🧪 Material
Compatibility |
Optimized for MS, CI, low carbon
steel, aluminum, copper, and steel |
Ensures reliable threading
across common industrial metals |
🔑 Key Advantages:
v Universal
Machine Fit: Universal Machine Compatibility Designed for maximum
adaptability; DRSA die-heads are compatible with horizontal lathes
for short-length threading lengths, as well as vertical drilling, milling machines and radial drilling machines
with rotating, reversing spindles - when equipped with a special MT
shank for short-length threading. They are also suitable for CNC, VMC
and HMC machines in short-threading applications, provided that each
threading cycle allows for manual door-opening to enable die-head locking. This
versatility makes them a dependable choice for both traditional and automated
machining setups.
v Non-Opening
Design: Ideal for machines that reverse the spindle to retract the tool,
eliminating the need for mechanical opening mechanisms.
v Threading
Flexibility: Supports both right-hand and left-hand threads with
dedicated chasers for each.
v Chaser
Compatibility: Accepts all standard Circular HSS chase sets, only
the proper chaser size is required.
v 4-Chaser
Configuration: Provides efficient and accurate threading for
general-purpose use.
v Material
Suitability: Optimized for ductile metals like MS, CI Casting, Low
Carbon Steel, Aluminium and Copper, and also suitable for Steel.
v Cost-Efficient
Threading: Achieve precise, high-speed threading across multiple sizes
using a single die-head - minimizing tooling costs and maximizing
productivity. Ideal for high-volume production environments where accuracy
and efficiency are critical.
v User
Requirement: For best performance, operation by a skilled machinist
& semi-skilled machinist is recommended.
v High-Speed
Output: Enables threading faster than SD Model and suited for rapid
multi-size threading at low cost.
⚡️Quick & Easy Installation – Model DRSA:
Installing Die Heads DRSA is designed to be quick and
efficient, especially for CNC machining centers and rotary transfer machines.
The DRSA model is a solid adjustable diehead that uses circular
chasers and does not open instead, it relies on reversing the
machine spindle for disengagement.
Quick Installation Guide for
DRSA Die Heads
- Prepare the Die Head
Ø Clean
the diehead and inspect for wear.
Ø Ensure
the spindle is compatible with the DRSA mounting specs.
- Insert Circular Chasers
Ø Match
the chasers to the thread size and pitch required.
Ø Slide
each chaser into its designated block slot.
Ø Secure
with screws and serrated bushings.
- Mount the Die Head
Ø Attach
the diehead to the machine spindle.
Ø Align
the diehead so the thread cutting direction matches the spindle rotation.
- Set Thread Depth and Feed
Ø Adjust
the machine’s feed rate and depth to match the diehead’s cutting range.
Ø DRSA
models are available for thread sizes from M6 to M28, depending on the
specific catalog number.
- Run a Test Cut
Ø Perform
a trial threading pass to verify alignment and thread quality.
Ø Make
fine adjustments as needed.
Chaser Sets for DRSA:
Crafted from high-speed steel
(HSS), these chasers are available in various thread angles and profiles to
suit a wide range of threading applications. Ideal for materials with hardness
up to 20 HRC.
🎯 High-Precision Features:
v Circular
Chaser Technology: Reduces rubbing, enhances chip clearance, extends
tool life, and ensures smooth thread profiles.
v 270°
Regrind Capability: Chasers can be reground through a full 270 degrees,
maintaining consistent throat geometry throughout their life.
v Heat
Dissipation: Robust chaser bodies and external mounting facilitate heat
dissipation for longer tool and machine life.
v Consistent
Thread Accuracy: Delivers uniform, high-quality threading across
large production volumes, ensuring minimal deviation and superior fit.
v Fine
Thread Diameter Adjustment: Equipped with knurled adjusting screws
and engraved calibration lines for micrometric regulation of thread size.
v Precision-Ground
Components: All critical parts are manufactured to close tolerances,
enabling seamless assembly, smooth performance, and reliable
interchangeability.
v Stable
Cutting Performance: Rigid construction and optimized cutting dynamics
reduce vibration, enhance surface finish, and extend tool life.
v Speed-Optimized
Operation: Performs efficiently within a wide RPM range (100–600),
with excellent results even on materials with hardness up to 20 HRC.
v Precision
Engineering: Designed for high-speed, accurate thread cutting,
suitable for low-volume production and heavy-duty jobs alike.
v Rugged
Construction: Built to withstand demanding production environments.
v Bidirectional
Threading: Suitable for both right-hand and left-hand threads.
v Extra-Light
Construction: Reduces spindle load, making it well-suited for high-speed
and automated operations.
v Externally
Mounted Chasers:
Ø
Allows threading right up to shoulders,
flanges, or other obstructions.
Ø
Provides excellent coolant access,
enhancing chip evacuation and tool longevity.
v Precision
Adjustability: Enables fine control over thread dimensions without
compromising rigidity or alignment.
📐 Technical Operating Range:
v Threading
Speed: Recommended threading speed: 100–600 RPM, depending on
material hardness, thread size/pitch, and chaser condition. (Always use
coolant for finish-grade threads and longer tap life.)
v Material
Hardness: 0–20 HRC
v Maximum Threading Length: Offers unlimited threading lengths on horizontal lathes, while supporting short-length threading applications on vertical drilling machines, milling machines, CNC, and VMC setups.
🛠️ Maintenance Note:
To extend the life of this tapping attachment or
any die head, die holder, or tap chuck avoid constant use at upper or lower
limit capacities. Consider rotating between two or three units for
heavy-duty applications.
🎯 Special Shanks: Please specify the desired shank type (e.g., Straight Shank, Straight Coolant) to ensure compatibility with your machine spindle. These are available upon request and may incur additional charges, subject to availability.
🔩 Key Highlights for Die Head
Maintenance
🛠️ Functional Inspection
v Chaser
Springs: Must operate smoothly no chips, no bending.
v Pins
in Block: Ensure they are straight and not fractured.
v Cams
on Die head Cup: Check edges for noticeable wear, which affects chaser
movement.
v Guide
Pins: Must be rigid within the adjusting plate. Replace if there's any
play.
📏 Alignment &
Geometry
v Adjusting
Plate: After replacing guide pins, inspect for warping. Warped plates cause
misalignment.
v Floating
Bushing: Should protrude visibly from the body hole to maintain guiding
accuracy.
🔍 Wear Components Check
v Plunger:
Remove and assess the control tip edge any damage can disrupt retraction
timing.
v Spring
Plunger: Ensure the spring retains good compression before reassembly.
🧼 Bonus Tips
v Always
clean components of chips and debris before inspection.
v Lubricate
wear points appropriately after each maintenance cycle.
v Document
findings for each die head to track performance over time.
🔧 Advantages of Circular Chasers
🌀 Optimized Shape for
Performance
v The
circular design ensures minimal rubbing just behind the cutting edge,
promoting better lead control.
v Reduces
friction and wear, resulting in smoother threads and extended chaser
life.
v The
chaser’s solid body and external mounting allow for rapid heat
dissipation and efficient chip removal ideal for higher cutting speeds.
🎯 Consistent Accuracy
v Delivers
precision threads immediately, eliminating the need for trial-and-error
adjustments.
v Features
annular thread forms with a factory-set helix angle that remains
consistent throughout the tool’s life.
🔄 Superior Regrinding
Capability
v Can
be re-ground through a full 270°, far surpassing the lifespan of
thin-blade alternatives.
v The
built-in throat grind maintains its geometry even after multiple
re-sharpenings.
v Simplified
grinding process ensures accurate, repeatable results with minimal
effort.
⚙️ Quick and Easy Replacement
v Chasers
are pre-mounted and precisely ground, enabling fast installation
without disturbing the setup.
v Replacement
takes seconds, thanks to user-friendly mechanisms like a screw turn or
reset handle—much faster than traditional systems.
🔁 Full Interchangeability
v Circular
tools are interchangeable between rotating and non-rotating heads, size
for size.
v By
adjusting the grind, the same chaser can be optimized for a wide range of
materials, enhancing versatility.
🧩 Exclusive Modular
Shanks
v Unique
to our circular chaser systems, modular shanks allow the same head to be
used across multiple machines.
v Reduces
tooling inventory, improves utilization, and minimizes downtime.
v Available
in standard and coolant-induced versions across various sizes (see pages
11).
🔩 4-Chaser Dieheads
v Offer
high production efficiency, accuracy, and cost-effectiveness.
v Their
size range and interchangeability make them one of the most versatile
threading tools available.
v Modular
shank design allows for easy adaptation to different machines and
reduces replacement costs.
🧱 Replaceable Plunger
Wear Insert
v All
dieheads include a hardened, replaceable plunger wear insert.
v Unlike
older designs with built-in grooves, this insert can be replaced affordably,
extending the life of the diebody.
v Prevents costly diebody replacements and ensures long-term durability.
🔩 Chaser Thread Standards
|
Thread |
Full Form |
Description |
|
NPT |
National Pipe Taper |
Tapered thread used in
U.S. pipe fittings. Creates a seal via thread interference. |
|
BSP |
British Standard Pipe |
Common in Europe and Asia.
Includes BSPT (tapered) and BSPP (parallel) threads. |
|
BSW |
British Standard
Whitworth |
Coarse thread with
rounded crests and roots. Used in older British machinery. |
|
UNF |
Unified National Fine |
Fine-pitch thread used in
precision applications. Part of the Unified Thread Standard. |
|
UNC |
Unified National
Coarse |
Coarse-pitch thread
for general fastening. Also part of the Unified Thread Standard. |
|
Metric |
ISO Metric Thread |
International standard. Uses
millimeter-based pitch and diameter. |
🧰 Where They're Commonly Used
v NPT:
Plumbing, gas lines, hydraulic systems (mostly in North America)
v BSP:
Water and fluid systems (Europe, Asia, Australia)
v BSW:
Restoration, vintage British equipment
v UNF/UNC:
Automotive, aerospace, general engineering (U.S. and Canada)
v Metric: Global standard for bolts, screws, and fasteners
🏭 Chaser Material - Performance Comparison
|
Feature |
M2 |
M2 + Coating |
M35 |
M35 + Coating |
|
Base
Material |
HSS
(no cobalt) |
Same
+ surface coating |
HSS
+ 5% cobalt |
Same
+ surface coating |
|
Heat
Resistance |
Moderate |
Improved |
High |
Excellent |
|
Wear
Resistance |
Good |
Better |
Very
Good |
Superior |
|
Tool
Life |
Standard |
Longer |
Long |
Longest |
|
Thread
Finish |
Acceptable |
Smoother |
Clean |
Best-in-class |
|
Cost |
Low |
Slightly higher |
Higher |
Highest |
|
Ideal
Use |
Mild
steel, alloys |
Medium-duty
runs |
Stainless,
tool steel |
High-speed,
tough jobs |
⚙️ Estimated Production Ratios
(Relative Tool Life)
|
Chaser
Type |
Relative
Tool Life |
Typical
Usage Ratio* |
|
M2 |
1×
(baseline) |
40–50% |
|
M2
+ Coating |
~1.5× |
20–25% |
|
M35 |
~2× |
15–20% |
|
M35
+ Coating |
~2.5–3× |
10–15% |
*These ratios reflect how often
each type might be used in a mixed production setup, assuming cost and
performance are balanced.
🔍 Production Insights
v M2
is suitable for short-run jobs or general-purpose threading where
cost is a priority.
v M2
with coating offers better performance in medium-duty production,
especially with coolant-assisted threading.
v M35
is built for demanding materials like stainless steel and excels in automated
setups.
v M35
with coating is the top-tier choice for continuous, high-speed
production with minimal downtime.
💡 Decision Tip
If your production involves frequent
threading of hard materials or long cycle times, investing in M35
with coating can reduce tool changes and improve consistency. But for cost-sensitive,
low-to-medium complexity jobs, M2 or M2 with coating may be more
economical.
🎯
"Intelligent
Quick-Analysis Tool Designed For Discerning Business Customers."
🎯
🛠️ DRSA Model Solid Adjustable Die-Heads – Dimensional Range Smart Overview
|
Diehead Model |
Threading Capacity (Metric) |
Threading Capacity (Inch) |
Suitable Chaser Set |
Approx Weight (Kg.) |
|
DRSA 9/16” |
7 – 14 mm |
1/4” – 9/16” |
9/16” |
0.900 Kg. |
|
DRSA 13/16” |
7 – 14 mm |
1/4” – 9/16” |
13/16” |
3.000 Kg. |
|
DRSA 1” |
7 – 20 mm |
1/4” – 13/16” |
1” |
3.100 Kg. |
|
DRSA 1-1/16” |
10 – 25 mm |
3/8” – 1” |
1-1/16” |
3.200 Kg. |
|
DRSA 1-5/8” |
13 – 27 mm |
1/2” – 1-1/16” |
1-5/8” |
5.400 Kg. |
🔩 DRSA
Series Revolving Solid
Adjustable Die Head – Quick Smart Summary
Designed for precision external threading in both manual and
automated setups, the DRSA Series die heads feature automatic opening, circular
chaser technology, and universal machine compatibility—ideal for high-speed,
high-volume production environments.
🔑 Key Features
v 🎯
Micrometric Diameter Control: Knurled screw with calibration lines
allows precise thread sizing.
v 🔄
Circular Chaser Technology: Reduces rubbing and improves chip clearance
for better finish and tool life.
v 🧰
Universal Compatibility: Fits lathes, drilling, milling, CNC, VMC, and
HMC machines.
v 🔁
Thread Direction Flexibility: Supports both right-hand and left-hand
threads with dedicated chasers.
v 🧪
Material Versatility: Suitable for MS, CI, low carbon steel, aluminum,
copper, and steel.
⚙️ Operating Highlights
v Threading
Speed Range: Efficient performance between 100–600 RPM depending on
material and chaser condition.
v Thread
Length Capability: Unlimited on horizontal lathes; short-length threading
supported on vertical and CNC machines.
v Quick Chaser Replacement: Four-screw cover plate enables fast maintenance.
📌 Safety &
Performance Tips
v Use
Coolant: Apply cutting fluid to enhance finish and extend tool life.
v Avoid
Overload: Rotate between units for heavy-duty use; avoid extreme capacity
limits.
v Correct
Setup: Ensure proper chaser seating and handle alignment before operation.
v Trial
Cut First: Always verify thread size with a trial cut before full
production.
🔩 DRSA
Series Revolving Solid
Adjustable Die Head – Quick Smart Analysis
|
Aspect |
Details |
|
🔧 Type |
Revolving Solid Adjustable Die Head – engineered
for high-speed external threading |
|
⚙️ Function |
Enables automatic die-head
opening at preset thread length without spindle reversal |
|
🔄 Mechanism |
Cam and stopper system
disengages die head smoothly after threading |
|
📐 Thread
Range |
Accommodates a wide range of
metric and imperial thread sizes using circular chasers |
|
🛠️
Applications |
Ideal for mass
production threading on lathes, CNCs, VMCs, HMCs, and milling machines |
|
✅ Advantages |
Enhances threading speed –
Improves surface finish – Reduces chaser wear and operator effort |
|
🏭 Use Case |
Compatible with center
lathes, turret lathes, drilling, milling, CNC, VMC, and HMC setups |
v Overview
: The DRSA Series Revolving Solid Adjustable Die Heads are
engineered for high-speed, precision external threading without the need for
spindle reversal. Key features include:
Ø Right-
and left-hand thread compatibility with dedicated chasers
Ø Micrometric
thread diameter adjustment via calibrated knurled screw
Ø Two-cut
threading mode (roughing and finishing) without tool change
Ø Precision-ground
components for vibration-free performance and superior finish
v Tap
Monitoring Integration (when paired with automated systems)
Ø Real-time
detection of torque spikes, misalignment, and dull chasers
Ø Evaluation
of thread engagement and clutch response
Ø Alerts
for inconsistencies in thread profile and feed rate
v Benefits
:
Ø Reduces
downtime through early fault detection
Ø Improves
thread quality and extends tool life
Ø Supports
predictive maintenance and operator feedback
v Ideal
For : High-volume or precision threading environments where consistency,
speed, and tool protection are essential—such as CNC, VMC, HMC, and
turret lathe setups.
















