UBACK® – Hydraulic Back Counterboring, Spotfacing & Countersinking System | NOGA MT
NOGA MT · ULTIMATE BACK SYSTEM

UBACK® Back-Machining System

Machine hidden rear features without flipping the workpiece. UBACK combines coolant-actuated UX tool-holders with USPOT and UCHAMF inserts for automated CNC back spotfacing, counterboring, chamfering and countersinking.

CNC AUTOMATION HYDRAULIC INSERT ACTUATION MIN. 6 BAR / 90 PSI PILOT Ø8–25 mm USPOT + UCHAMF
NOGA MT UBACK back-machining tool operating through a workpiece
One UX holder platform. Two insert families. USPOT for back spotfacing / counterboring · UCHAMF for back chamfering / countersinking.
UBACK AT A GLANCE

Reach the back side in one CNC setup.

UBACK uses spindle coolant pressure to control insert deployment inside the UX tool-holder, allowing the cutting edge to pass through an existing pilot hole, open behind the feature, machine the rear face, retract and return safely.

Application Hidden rear features No workpiece flipping required.
Pilot Hole Ø8–25 mm 0.315–0.984″ UX range.
Actuation Hydraulic Internal coolant, emulsion or air.
Pressure Min. 6 bar 90 PSI minimum operating pressure.
Insert Families USPOT + UCHAMF Counterbore / spotface / chamfer / countersink.
Tool-Holders UBACK UX DURASHIELD corrosion-resistant platform.
CHOOSE THE CUTTING SOLUTION

One UBACK platform. Two rear-machining insert families.

Start from the feature you need to produce. The insert series must match the selected UX tool-holder series.

USPOT · US INSERT FAMILY

Back Spotfacing & Counterboring

Produce a flat-bottom rear spotface or counterbore through an existing pilot hole. USPOT is a semi-standard solution configured to the required application diameter, corner radius, chip-former and coating.

  • Flat-bottom back spotface / counterbore.
  • Target ØD tolerance ±0.1 mm / ±0.004″.
  • Supports continuous and interrupted-cut applications.
  • Maximum standard UX/USPOT envelope up to Ø57.5 mm.
USPOT back spotfacing application CLICK TO ENLARGE
UCHAMF · UC INSERT FAMILY

Back Chamfering & Countersinking

Machine hidden rear chamfers and countersinks with standard 82° or 90° UCHAMF inserts, with special-angle solutions available for customer-specific applications.

  • Rear countersinking and controlled back chamfering.
  • 82° and 90° standard insert families.
  • Special angles available on request.
  • Same coolant-actuated UX tool-holder platform.
UCHAMF back chamfering and countersinking application CLICK TO ENLARGE
WHY UBACK

Designed to remove extra setups from rear-feature machining.

The UX hydraulic mechanism turns internal coolant pressure into repeatable insert movement, allowing hidden features to be machined from the accessible side of the part.

01 Single-Setup Machining Reach the rear face through the pilot hole instead of flipping or reclamping the component.
02 Automated Insert Movement Coolant pressure opens and retracts the insert for CNC-compatible unattended cycles.
03 One Holder Platform Use the same UX architecture with USPOT or UCHAMF inserts according to the required feature.
04 Pilot-Hole Protection The closed insert passes through the pilot hole before deployment behind the workpiece.
05 Continuous or Interrupted Cuts The system supports common rear-face geometries, with coolant strategy adjusted to the cutting condition.
06 Replaceable Inserts Insert replacement uses a standardized screw/pin approach without a dedicated mounting jig.
07 Material-Specific Cutting Data Technical recommendations cover ISO material groups, chip-formers, coatings and series-specific feeds.
08 Configurator + G-Code Match insert and UX holder, validate the geometry and generate CNC program guidance from one workflow.
SYSTEM LOGIC

From pilot hole to finished rear feature.

STEP 1 Enter with the insert closed

The folded insert and UX tool-holder pass through the existing pilot hole without cutting.

STEP 2 Activate coolant pressure

Internal coolant, emulsion or air activates the hydraulic piston and deploys the insert.

STEP 3 Machine the back feature

Perform the USPOT counterbore/spotface or UCHAMF countersink/chamfer on the hidden surface.

STEP 4 Retract and exit

Stop/redirect actuation according to the programmed sequence, close the insert and return through the pilot.

UX TOOL-HOLDER RANGE

Series B–G cover pilot holes from Ø8 to Ø25 mm.

Select the UX series from the pilot-hole diameter first. Then verify the requested feature diameter and axial reach against the selected holder and insert family.

Series Pilot-Hole Range Ød USPOT Max ØD UCHAMF 82° Max ØD UCHAMF 90° Max ØD UX Holder Shank
B8–10 mm / 0.315–0.394″23 mm / 0.906″17 mm / 0.669″18 mm / 0.709″Ø16 mm
C11–13 mm / 0.433–0.512″30 mm / 1.181″24 mm / 0.945″25 mm / 0.984″Ø16 mm
D14–16 mm / 0.551–0.630″37 mm / 1.457″29 mm / 1.142″31 mm / 1.220″Ø20 mm
E17–19 mm / 0.669–0.748″44 mm / 1.732″34 mm / 1.339″37 mm / 1.457″Ø20 mm
F20–22 mm / 0.787–0.866″50.5 mm / 1.988″39 mm / 1.535″42 mm / 1.654″Ø25 mm
G23–25 mm / 0.906–0.984″57.5 mm / 2.264″44 mm / 1.732″47 mm / 1.850″Ø25 mm

Selection rules: insert series must match UX holder series; application axial reach must remain within the holder RFC limit. USPOT requested ØD is application-specific; UCHAMF 82°/90° values shown are the maximum standard diameters at the upper pilot size of each series.

HOW IT WORKS

Hydraulic insert control using the machine’s existing coolant system.

The UX holder converts pressure through the spindle into controlled insert movement. This makes the system suitable for automated back-machining cycles on CNC machines.

OPERATING PRINCIPLE

Pressure controls the cutting position.

1
Closed during entryThe insert remains within the holder envelope while passing through the pilot hole.
2
Coolant actuates the mechanismMinimum operating pressure: 6 bar / 90 PSI.
3
Cut on the hidden sideUSPOT or UCHAMF performs the programmed rear-feature operation.
4
Close before returnThe insert retracts before the tool passes back through the pilot hole.
APPLICATION CONDITIONS

Built for more than a simple flat rear face.

UBACK supports continuous and interrupted rear-feature machining. For interrupted conditions, use the cooling and cutting-data reductions specified in the Technical Center.

UBACK counterbore on cylindrical bore ENLARGE
Cylindrical Bore Rear counterbore/spotface on a cylindrical geometry. INTERNAL COOLANT
UBACK counterbore on sloped surface ENLARGE
Sloped Surface Machining a rear spotface/counterbore where the back surface is inclined. EXTERNAL COOLANT
UBACK fully interrupted counterbore on slot ENLARGE
Slot / Interrupted Cut Fully interrupted rear machining across an open slot or broken surface. EXTERNAL COOLANT · REDUCE DATA
UBACK interrupted rear shoulder cutting condition type A ENLARGE
Shoulder Type A / Interrupted Cut Fully interrupted shoulder geometry with reduced cutting stability. EXTERNAL COOLANT · REDUCE DATA
UBACK interrupted rear shoulder cutting condition type B ENLARGE
Shoulder Type B / Interrupted Cut Alternative fully interrupted shoulder condition with repeated entry and exit. EXTERNAL COOLANT · REDUCE DATA
UBACK TECHNICAL CENTER

Programming, cutting data, cooling and insert technology.

Use the shared Technical Center for USPOT and UCHAMF programming sequences, continuous and interrupted-cut guidance, insert replacement, cooling-system setup, coatings, chip-formers and material-specific cutting recommendations.

Continuous CutCNC sequence and cooling logic.
Interrupted CutExternal coolant and reduced cutting parameters.
Cutting RecommendationsISO material groups and B–G series feed data.
Insert ReplacementStandardized pin, screw and key workflow.
Cooling SystemsEmulsion, air and MQL configuration.
Coatings & Chip-FormersPL / ML / HL and coating selection.
NOGA MT UBACK DURASHIELD tool-holder family
DURASHIELD UX TOOL-HOLDERS

Built for strength, corrosion resistance and repeatable CNC use.

UBACK UX holders are part of the NOGA MT DURASHIELD tool-holder platform. The holders use corrosion-resistant material and passivation to support demanding production environments while maintaining structural integrity and repeatable insert movement.

StrengthSupports demanding cutting loads.
ToughnessReliable under repeated production cycles.
Wear ResistanceLong-term holder durability.
Heat ResistanceStable performance in machining environments.
Corrosion ResistancePassivated protection for harsh conditions.
PrecisionConsistent hydraulic insert deployment.
FAQ

Common UBACK selection questions.

What is the difference between USPOT and UCHAMF?
USPOT is used for flat-bottom back spotfacing and counterboring. UCHAMF is used for back chamfering and countersinking, with standard 82° and 90° options plus special angles on request.
What pressure is required to operate UBACK?
The hydraulic insert mechanism requires a minimum of 6 bar / 90 PSI. The system can operate with internal coolant, emulsion or air according to the holder configuration.
What pilot-hole diameters are covered?
Standard UX tool-holders cover pilot-hole diameters from Ø8 to Ø25 mm (0.315–0.984″), organized in series B through G.
Can UBACK machine interrupted cuts?
Yes. Interrupted applications require the specific cooling strategy and cutting-data reductions defined in the UBACK Technical Center. Fully interrupted cuts use external coolant.
Can one UX holder use both USPOT and UCHAMF?
The UX platform is common to both insert families, but the insert series must match the UX holder series and the application dimensions must remain inside the holder limits.
Are the holder and insert sold together?
UX tool-holders and UBACK inserts are selected as a matched system but are supplied as separate items.
How do I select the correct UBACK tool?
Start with the pilot-hole diameter, select the corresponding UX series, then define the required rear feature and verify ØD and axial reach. The UBACK Configurator can perform this matching workflow.
Can NOGA MT support a special application?
Yes. For application review, send the part drawing or feature sketch together with workpiece material, pilot diameter, required rear-feature dimensions and machine/coolant information.
NEED HELP SELECTING UBACK?

Send the application drawing and let NOGA MT check the complete setup.

Include the pilot-hole diameter, rear-feature geometry, axial reach, workpiece material and available coolant pressure. We can help match the UX holder, insert family and starting cutting data.