Thread Adapters
OVERVIEW
Threading Adapters
- Machined from Stainless Steel
- Adapts to other Common Thread Standards
- Ideal for Mounting Posts
Thorlabs' selection of thread adapters offers numerous options for switching between M2.5, M3, M4, M6, #4-40, #6-32, #8-32, and 1/4"-20 thread sizes. Choose from external-to-internal, external-to-external, or internal-to-internal thread adapters. We also offer internal-to-external threaded stud adapters.
The Mini-Series thread adapters can be used to make the Mini-Series posts compatible with our extensive range of optical mounts.
Counterbore Adapters
Threaded counterbore adapters are used to convert a counterbore to a threaded hole. A part such as the KM100 kinematic mirror mount features counterbores to provide imperial and metric compatibility. A caphead screw is typically used to fasten these mounts to a post, but in some instances it is necessary to attach the mount to a post with a fixed threaded stud. The counterbore adapter thus allows parts, such as the KM100, to be post mounted when a capscrew cannot be used.
The SD1 is an adapter ring that provides a means to attach #8-32 (M4) tapped components to 1/4"-20 (M6) counterbored parts. One possible use of the SD1 is in a dovetail optical rail setup where the RC1 rail carriers feature a 1/4" (M6) counterbore. Optic mounts are commonly attached to RC1 rail carriers and usually require the SD1 adapter as most optic mounts are #8-32 (M6) tapped.
Thread Adapters - External to External
| Item # | Thread A | Thread B | Length C |
|---|---|---|---|
| AP4M3M | M4 | M3 | 0.38" (9.5 mm) |
| AP6M4M | M6 | M4 | 0.57" (15 mm) |
| AP8E4E | #8-32 | #4-40 | 0.38" (9.5 mm) |
| AP6M8E | M6 | #8-32 | 0.57" (15 mm) |
| AP8E25E | #8-32 | 1/4"-20 | 0.57" (15 mm) |
| AP8E4M | #8-32 | M4 | 0.48" (12.2 mm) |
| AP25E6M | 1/4"-20 | M6 | 0.57" (15 mm) |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
AP4M3M |
Thread Adapter, External to External, M4 to M3 |
$1.90 |
Today |
AP6M4M |
Thread Adapter, External to External, M6 to M4 |
$1.90 |
Today |
AP8E4E |
Thread Adapter, External to External, 8-32 to 4-40 |
$1.90 |
Today |
AP6M8E |
External Thread Adapter, M6 to 8-32 Threads |
$1.90 |
Today |
AP8E25E |
External Thread Adapter, 8-32 to 1/4"-20 Threads |
$1.90 |
Today |
AP8E4M |
Customer Inspired!Thread Adapter, External to External, M4 to 8-32 |
$1.90 |
Today |
AP25E6M |
External Thread Adapter, 1/4"-20 to M6 Threads |
$1.90 |
Today |
Thread Adapters - Internal to External
| Item # | Thread A | Thread B | Length C |
|---|---|---|---|
| AS4M8E | M4 | #8-32 | 0.56" (14 mm) |
| AS8E4M | #8-32 | M4 | 0.56" (14 mm) |
| AS6M25E | M6 | 1/4"-20 | 0.63" (16 mm) |
| AS25E6M | 1/4"-20 | M6 | 0.63" (16 mm) |
| AS25E8E | 1/4"-20 | #8-32 | 0.61" (15 mm) |
| AS6M4M | M6 | M4 | 0.61" (15 mm) |
| AS25E4M | 1/4"-20 | M4 | 0.61" (15 mm) |
| AS6M8E | M6 | #8-32 | 0.61" (15 mm) |
| AS8E25E | #8-32 | 1/4"-20 | 0.68" (17 mm) |
| AS4M6M | M4 | M6 | 0.68" (17 mm) |
| AS4M25E | M4 | 1/4"-20 | 0.68" (17 mm) |
| AS8E6M | #8-32 | M6 | 0.68" (17 mm) |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
AS4M8E |
Thread Adapter, Internal to External, M4 to 8-32 |
$4.10 |
Today |
AS8E4M |
Thread Adapter, Internal to External, 8-32 to M4 |
$4.10 |
Today |
AS6M25E |
Thread Adapter, Internal to External, M6 to 1/4"-20 |
$4.10 |
Today |
AS25E6M |
Thread Adapter, Internal to External, 1/4"-20 to M6 |
$4.10 |
Today |
AS25E8E |
Thread Adapter, Internal to External, 1/4"-20 to 8-32 |
$4.10 |
Today |
AS6M4M |
Thread Adapter, Internal to External, M6 to M4 |
$4.10 |
Today |
AS25E4M |
Thread Adapter, Internal to External, 1/4"-20 to M4 |
$4.10 |
Today |
AS6M8E |
Thread Adapter, Internal to External, M6 to 8-32 |
$4.10 |
Today |
AS8E25E |
Thread Adapter, Internal to External, 8-32 to 1/4"-20 |
$4.10 |
Today |
AS4M6M |
Thread Adapter, Internal to External, M4 to M6 |
$4.10 |
Today |
AS4M25E |
Thread Adapter, Internal to External, M4 to 1/4"-20 |
$4.10 |
Today |
AS8E6M |
Thread Adapter, Internal to External, 8-32 to M6 |
$4.10 |
Today |
Thread Adapters - Internal to External Threaded Stud
| Item # | Thread A | Thread B | Length C |
|---|---|---|---|
| AE3M25E | M3-0.5 | 1/4"-20 | 0.38" (9.5 mm) |
| AE3M6M | M3-0.5 | M6-1.0 | 0.39" (10 mm) |
| AE4E25E | #4-40 | 1/4"-20 | 0.38" (9.5 mm) |
| AE4E6M | #4-40 | M6-1.0 | 0.39" (10 mm) |
| AE6E25E | #6-32 | 1/4"-20 | 0.38" (9.5 mm) |
| AE6E6M | #6-32 | M6-1.0 | 0.39" (10 mm) |
| AE4M6M | M4-0.7 | M6-1.0 | 0.39" (10 mm) |
| AE4M25E | M4-0.7 | 1/4"-20 | 0.38" (9.5 mm) |
| AE8E6M | #8-32 | M6-1.0 | 0.39" (10 mm) |
| AE8E25E | #8-32 | 1/4"-20 | 0.38" (9.5 mm) |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
AE3M25E |
Thread Adapter, Internal to External Stud, M3 x 0.5 to 1/4"-20 |
$4.10 |
Today |
AE3M6M |
Thread Adapter, Internal to External Stud, M3 x 0.5 to M6 x 1.0 |
$4.10 |
Today |
AE4E25E |
Thread Adapter, Internal to External Stud, 4-40 to 1/4"-20 |
$4.10 |
Today |
AE4E6M |
Thread Adapter, Internal to External Stud, 4-40 to M6 x 1.0 |
$4.10 |
Today |
AE6E25E |
Thread Adapter, Internal to External Stud, 6-32 to 1/4"-20 |
$4.10 |
Today |
AE6E6M |
Thread Adapter, Internal to External Stud, 6-32 to M6 x 1.0 |
$4.10 |
Today |
AE4M6M |
Thread Adapter, Internal to External Stud, M4 x 0.7 to M6 x 1.0 |
$4.10 |
Today |
AE4M25E |
Thread Adapter, Internal to External Stud, M4 x 0.7 to 1/4"-20 |
$4.10 |
Today |
AE8E6M |
Thread Adapter, Internal to External Stud, 8-32 to M6 x 1.0 |
$4.10 |
Today |
AE8E25E |
Thread Adapter, Internal to External Stud, 8-32 to 1/4"-20 |
$4.10 |
Today |
Thread Adapters - Internal to Internal
| Item # | Thread A | Thread B | Length C |
|---|---|---|---|
| AI25E8E | #8-32 | 1/4"20 | 0.5" (13 mm) |
| AI6M4M | M4 | M6 | 0.5" (13 mm) |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
AI25E8E |
Thread Adapter, Internal to Internal, 1/4"-20 to 8-32 |
$4.70 |
Today |
AI6M4M |
Thread Adapter, Internal to Internal, M6 to M4 |
$4.70 |
Today |
Mini-Series Thread Adapters
- Machined from Stainless Steel
- Adapts to Other Common Thread Standards
| Item # | Thread A | Thread B | Length C |
|---|---|---|---|
| MSA8 | 4-40 | 8-32 | 0.5" (13 mm) |
| MSA4/M | M3 | M4 | 0.5" (13 mm) |
| MSA25 | 4-40 | 1/4"-20 | 0.55" (14 mm) |
| MSA6/M | M3 | M6 | 0.55" (14 mm) |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
MSA25 |
Thread Adapter, External Stud to Internal, 1/4"-20 to 4-40 |
$4.90 |
Today |
MSA8 |
Thread Adapter, External Stud to Internal, 8-32 to 4-40 |
$4.90 |
Today |
MSA4/M |
Thread Adapter, External Stud to Internal, M4 to M3 |
$4.90 |
Today |
MSA6/M |
Thread Adapter, External Stud to Internal, M6 to M3 |
$4.90 |
Today |
Threaded Counterbore Adapters
- Converts a Counterbored Clearance Hole into a Tapped Hole
- Slotted Edge for Tightening
- Designed for Slip Fit with Thorlabs' Counterbores
Threaded counterbore adapters are used to convert a counterbore into a threaded hole. A part such as the KM100 Kinematic Mirror Mount features a counterbore that provides imperial and metric compatibility; a cap screw is typically used to fasten the mount to a post. In some instances, it may be necessary to attach the mount to a post with a fixed threaded stud. The counterbore adapter facilitates this mounting option. These adapters feature a slotted edge that enables tightening or removal.
| Item # | Internal Thread (A) | Outside Diameter (B) | Use in C-Bore |
|---|---|---|---|
| CBA8E | 8-32 | 0.28" (7.0 mm) | #8 |
| CBA25E | 1/4"-20 | 0.40" (10.2 mm) | 1/4" |
| CBA4M | M4-0.7 | 7.0 mm (0.28") | M4 |
| CBA6M | M6-1.0 | 10.2 mm (0.40") | M6 |
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
CBA8E |
8-32 Tapped Counterbore Adapter |
$7.20 |
Today |
CBA25E |
1/4"-20 Tapped Counterbore Adapter |
$7.20 |
Today |
CBA4M |
M4 x 0.7 Threaded Counterbore Adapter |
$7.20 |
Today |
CBA6M |
M6 x 1.0 Threaded Counterbore Adapter |
$7.20 |
Today |
Counterbore Adapter Rings
- Allows a #8 (M4) cap screw to be used within a 1/4" (M6) counterbore
- Solid stainless steel design
- Sold in packages of 10
The SD1 adapter ring allows a #8 (M4) cap screw to be used within the 1/4" (M6) counterbore of many parts including rail carriers, BA2 mounting bases, etc. Most of our optomechanical components, such as our compact mirror mounts, feature tapped #8-32 (M4) holes, which this adapter is designed for. For example, the VC1 small V-clamp can mount directly to a BA1 base when an SD1 adapter is used with a #8-32 cap screw.
Part Number |
Description |
Price |
Availability |
|---|---|---|---|
SD1 |
1/4" (M6) Counterbore Adapter Ring for 8-32 (M4) Screws, 10 per Pack |
$7.20 |
Today |