ER25-04
ER Style Integrated Collet and End Mill Extension Holder
ER25 End Mill Extension Holder, 0.125in Hole Diameter, 0.394in Extension Diameter, 1in Extension Length
Solid ER-mill extensions
- Reaches micro tools past fixturing that a standard holder can't clear
- Holds exceptional runout at extended reach — TIR under .0002″ at full extension
- Beats deflection and chatter on long, small-diameter work
- Set screws grip the shank in a triangular arrangement for repeatable accuracy
- Internal stop adjusts from both ends with a standard hex key
- Precision-ground ER taper twists and snaps into most standard ER clamping nuts — available ER8 through ER25
- Coolant-Thru versions available in ER16
From the RobbJack Applications Guide.
About this series
ER Solid ER-Mill Extensions
Reach deep into fixtures without giving up accuracy.
Integrated ER collet-and-extension holders that let miniature and standard end mills clear fixturing and run at extended length while holding exceptional runout — solving the deflection and chatter that come with long, stacked tool assemblies.
- Precision-ground ER taper — available in ER8, ER11, ER16, ER20 and ER25
- Internal stop adjusts from both ends of the holder with a standard hex key
- Set screws clamp the shank in a triangular arrangement for excellent accuracy
- Coolant-thru versions available for ER16
Twist and snap into most standard ER clamping nuts — RobbJack recommends HiQ® by REGO-FIX for best results.
Headline spec
TIR < .0002" at full extension
Best for
- Deep-pocket & fixture clearance
- Micro tools at reach
- High-accuracy finishing
Specifications
US machining terms with ISO 13399 codes.
- Accessory Type
- ER Holder
- ER Size
- ER25
- Hole Diameter
- 0.125″
- Body DiameterDMM
- 0.394″
- Extension LengthOAL
- 1″
- Series
- ER — ER Style Integrated Collet and End Mill Extension Holder
See it run
Made & shipped in the USA · lead time confirmed at order. Buy at retail or through your distributor.
Performance guaranteed. Run it against the tool you use today — if it doesn't beat it, we'll make it right.
Adds Uncoated · $421.10 — our pick for your material. Choose another finish below.
Proven in the field
- $548,290saved per year drilling carbon-fiber aircraft
- $216,000saved per year trimming aircraft skins
- 1,000%metal-removal increase in Inconel 718 (SPS)
Finishes (1)
Uncoated
ER25-04
$421.10
Available to order
Starting at
$421.10
Performance guaranteed
More in the ER series
Same series, different size — what changes from this tool is shown in red.