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Manual Parallel-Coupled BiSlideMotorized Parallel-Coupled BiSlide Parallel-Coupled BiSlide Light Box Duo Parallel-Coupled BiSlide Belt-driven Parallel-Coupled Bislide

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Parallel-Coupled BiSlide Assemblies

Velmex's Parallel-Coupled BiSlide Assemblies are the ideal solution for applications with large loads or long spans. Two identical BiSlide Assemblies are coupled together and synchronized to deliver the travel distance and payload capacity required by the application.

The system features two identical Velmex linear BiSlide Assemblies coupled with a timing belt to drive synchronous operation. It can handle loads to 600 lbs. (272 kg) and is available in many standard lengths up to 80 inches (203.2 cm).

The Parallel-Coupled BiSlide Assembly is available in both manual and motor-driven models. The motorized models feature a double shaft motor on one slide and a heavy-duty bearing assembly on the other slide. The manually-operated versions have the bearing assembly on both slides. A knob and crank drives the timing belt which in turn drives the lead screws.

It is possible to also parallel-couple Belt-Driven BiSlides. While Belt-Driven BiSlides typically handle lighter loads and faster speeds, the advantages of both systems can be incorporated into one. By doing so you increase the size of the payload the Belt-Drive system can handle while at the same time, increasing the speed and the traverse of the Parallel-Coupled BiSlide. Belt-driven systems feature a drive shaft coupling in place of the timing belt to synchronized the operation of the parallel BiSlides.

Constructed with hard-coat anodized, aluminum dovetail ways and smooth motion PTFE linear bearings; BiSlide Assemblies deliver higher rigidity for longer life and more precise movement. Longer traverses include specially-designed separators mounted perpendicular to the base to keep the system in parallel and add extra stability. The entire system is comprised of our proven BiSlide I-beam design and has all the same features of renown Velmex BiSlide stages.

Parallel-Coupled BiSlide® Assembly Features

Because the Parallel-Coupled BiSlide Assembly is a configuration of the linear Velmex BiSlide Assemblies, it has many of the same features and benefits found on the world-recognized BiSlide positioning stages.

Parallel-Coupled BiSlide Features

Parallel-Coupled BiSlide® Style Options

Parallel-Coupled Manual  BiSlide

Manual Parallel-Coupled Assembly - Two or more identical manual single-axis lead-screw BiSlides are coupled together to handle larger loads and longer traverses. The operation of the BiSlides are kept in synch through a timing belt. (Part number prefix "PC1".)

Parallel-Coupled Motorized  BiSlide

Motorized with Lead Screw - Each axis is usually comprised of 2 identical motorized, lead screw versions of the BiSlide positioning stage. The stages are synchonized through a timing belt coupling. (Part number prefix "PC2".)

Parallel-Coupled Belt-Driven BiSlide

Motorized Belt-Driven -Basically the same as a lead screw version, except this is comprised of 2 identical Belt-Driven BiSlide positioning stages. The stages are synchonized through a drive shaft coupling. (Part number prefix "PC2B".)

Pictured is a system comprised of a Parallel-Coupled Belt Drive with a single axis Belt Drive BiSlide in the Y axis and a lead screw BiSlide in the Z axis.

Please refer to either manually-operated or motor-driven BiSlide Assemblies for additional details, specifications and examples of other BiSlide models, series and styles.

Parallel-Coupled BiSlide® Specifications

Factors such as size of the motor, size of the payload, travel distance, mounting direction/plane, etc. effect the actual capability of any assembly. Please contact Velmex Application Engineers to configure a system that will meet your exact requirements.

BiSlide® Travel Distance Base Length Slider Length
Series Inches cm Inches cm Inches cm
PC1 – Parallel-Coupled - manual Parallel-Coupled BiSlide up to 80" up to 203.2 Standard offering: 8" to 80" center to center measurement. Because most Parallel-coupled BiSlides are custom other specifications will depend on design and the components of the specific system. Talk to a Velmex Application Engineer.
PC2 – Parallel-Coupled - motorized* Two Parallel Coupled  BiSlides up to 80" up to 203.2
PC2B – Parallel-Coupled, Belt-Drive - motorized* Parallel-Coupled Belt-Drive  BiSlide up to 220" up to 559

* Motors sold separately

Parallel-Coupled BiSlide® Dimensions
  Parallel-Coupled  BiSlide Dimensions  

BiSlide Cross Section

BiSlide Base Cross-Section

The slider / carriage (shaded area in the cross-section to the left) rides inside the guide ways. The 45 degree opposing ways give strength to carry the payload.



Options/Accessories for Parallel-Coupled Velmex BiSlides®

See BiSlide Options and Accessories for more detailed information on the options and accessories that could be used on the Parallel-Coupled BiSlide Assembly. Here are a few of the more common ones.

BiSlide Framing

Framing (Manual or Motorized Series) – The versatility of the BiSlide's modular design enables building of complex configurations. A variety of framing components can be combined and connected, disassembled and reassembled in alternate configurations to build BiSlide structures as needed. Included in the framing available are T-Slot Plate, I-Beam Base, T-Nuts, mounting bolts and other hardware.

Framing components are used with the Parallel-Coupled BiSlide to keep the two slides parallel and deliver added strength and stiffness. The number of supports needed will depend on the travel length and direction of the system. For more specifics and to see the framing components, including plates and brackets, in use on a Velmex stage visit the BiSlide Adapters page.

BiSlide Cleats

Cleats (Manual or Motorized Series) - use BiSlide cleats to create rigid attachments, mountings for optical tables and attachments to other T-slot framing systems. The cleats are also used to secure BiSlides for longer travel distances and to support larger loads. Cleating Recommendations.


MC-1 – Standard 1 hole cleat. Mounts the BiSlide to a frame / base / surface. Can be used to mount to other BiSlides in an XY, XZ or XYZ configuration.
MC-2 – Standard 2 hole cleat. Mounts the BiSlide to a frame / base / surface. Can be used to mount to other BiSlides in an XY, XZ or XYZ configuration.
MC-3 – For use with optical benches with 1" or 25 mm centers
MC-4 Sandwich cleats - used to connect two parallel bases.

Revolution Counter on BiSlide

Revolution Counter (Manual Series) - A digital revolution counter delivers an absolute mechanical type readout. The counter is standard on Knob/Crank with counter and thumb lock style BiSlides.

Travelling Slider Lock on BiSlide

Motion Locks: (Manual Series)


Thumb Lock (-TL) An easy method to fix the slider utilizing a simple thumbscrew. A thumb lock is found on both the Knob style or Knob with counter style BiSlide. (standard) The lock applies friction to the knob input shaft, locking the carriage in place.
Slider Lock (-SL) This lock attaches to the slider to lock the carriage in place. (optional) (pictured)

VRO with a BiSlide Assembly

Encoders and VRO™ Encoder Readout (Manual or Motorized) For a high resolution position readout an encoder and Velmex's VRO encoder readout can be mounted to the linear slides. An encoder, mounted directly to the slider gives a true and accurate reading eliminating lead screw and backlash errors.

The VRO is compatible with all 5V incremental encoders. Fully functional, it features automatic memory back-up of settings, sleep mode and self diagnostics. It’s highly visible, wide-screen LED display makes it easy to view the positioning results. SEE: Velmex Controls on the Encoders and the VRO Readout for additional details.

Limit Switches on BiSlide

Outboard Adjustable Limit Switches (Motorized) – Mounted in a track on the side rib of Velmex BiSlide Assemblies to prevent over-travel. An optional third limit switch can be added between the two standard limits and used as an adjustable home switch. See Limits for more information.


VXM Controller with XY BiSlides

Motors and Motor-Controllers - A variety of motors are available to power Velmex UniSlides, most popular of which is the DC step motor. Integrated gear reduction motors are also available for economical operation. Servo motors are also used with the Belt-Drive BiSlide Assembly.

Motors coupled with a motor controller like the Velmex VXM™ are a cost effective solution for accurate speed and precise incremental positioning. Gear motors, servo motors and high resolution step motors in both AC and DC can run Velmex BiSlides. SEE: Velmex Controls on the Motors and Velmex Controls on the VXM Controller for additional details.


For .STP files, you may need to right click on the download button and save the "target" or "link".

Parallel-Coupled BiSlide CAD Drawings
Click to Open

The majority of CAD drawing found in our Technical Library are Step (.stp) files. You will also see .dxf, .dwg, .sat and .pdf files. If you require a different format or cannot located the drawing you require, please contact us. Drawings are identified by the series/model part no. The number can be found on the side or end of any Velmex device you may already own.

Series Type File Name Description Download View
PC2 SAT BiSlide Parallel Coupled XX 33in ctr to ctr 25in travel 2 supports.sat Motorized, Parallel-Coupled BiSlide with 25" Travel, set 33" center to center, with 2 supports to the frame Download Button -
PC2 STP BiSlide Parallel Coupled XX 33in ctr to ctr 25in travel 2 supports.stp Motorized, Parallel-Coupled BiSlide with 25" Travel, set 33" center to center, with 2 supports to the frame Download Button -
PC2 SAT BiSlide Parallel Coupled XX 33in ctr to ctr 30in travel 2 supports.sat Motorized, Parallel-Coupled BiSlide with 30" Travel, set 33" center to center, with 2 supports to the frame Download Button -
PC2 STP BiSlide Parallel Coupled XX 33in ctr to ctr 30in travel 2 supports.stp Motorized, Parallel-Coupled BiSlide with 30" Travel, set 33" center to center, with 2 supports to the frame Download Button -
PC2B SAT BiSlide Beltdrive Parallel 120in ctr to ctr.sat Motorized, Parallel-Coupled, Belt-Driven BiSlide with ±100" Travel, set 120" center to center, with 2 supports to the frame Download Button -
PC2B STP BiSlide Beltdrive Parallel 120in ctr to ctr.stp Motorized, Parallel-Coupled, Belt-Driven BiSlide with ±100" Travel, set 120" center to center, with 2 supports to the frame Download Button -



Parallel-Coupled BiSlide Documents / Instructions
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Parallel-Coupled BiSlide Documents

Type File Name Description Download View
PDF Parallel-Coupled BiSlide Dimensional Drawings.pdf Dimensional drawings for the Parallel-Coupled BiSlide Download Button View PDF



Velmex Belt-Driven BiSlide® Applications and Examples

These are examples of Velmex products. If you wish a similar product, please contact us with your specific application specifications (travel distance, payload, hours per day in use, resolution, speed range, etc.). You can use the Request Assistance form.

The example displayed may be a custom configuration, designed to the customer's specifications; and not offered as a standard product. Custom configurations could contain custom, externally-fabricated components.

Pictured in our gallery are examples of configurations for the Belt-Driven BiSlide, along with configurations that also include other Velmex products. Product and accessory offering is subject to change and availability.

Example Key Code Meaning Example Key Code Meaning
A Manually Operated M Motorized
S Standard C Custom Configuration
B BiSlide U UniSlide
X XSlide R Rotary Tables
T XY Tables TT Turntables
E Elevating Tables FS Fun Stuff (Ingenious, Cool, or Just out of the ordinary applications)


Single Axis (XX) Parallel-Coupled BiSlide Stages
Click to Open
  • Parallel-Coupled Manual  BiSlide description
    Exp: ASB10
  • Motorized Parallel-Couled BiSlide description
    Exp: MSB11
  • Parallel-Coupled Belt-Driven BiSlide description
    Example: MCB2

Multiple-Axes Belt-Driven BiSlide Assemblies
Click to Open
  • Parallel -Coupled  BiSlide Assembly description
    Example: MCB1
  • Multiple Parallel-Coupled BiSlides description
    Example: MSB1
  • Parallel-Coupled XY Belt Drive description
    Example: MCB3
  • Parallel-Coupled XZ description
    Example: MCB4
  • Parallel-Coupled Z axis description
    Example: MCB5

Combination Assemblies
Click to Open
  • Multiple axis BiSlide with Belt-Driven BiSlide description
    Example: MCBB1
  • Parallel and Tandem BiSlide description
    Example: MCBB2

Working Images
Click to Open
  • Side Knob BiSlide with Scope description
    Door Inspection
  • Side Knob BiSlide with Scope description
    Cyclotron Lab

Examples of other Velmex products can be found on the Examples page or in the Examples section for each product.




Many questions can be answered by reviewing the "Features", "Model / Series", "Specifications", "Options / Accessories" and "Technical Documentation" sections for each product line. Additional FAQs about product comparisons, product construction, purchasing and shipping can be found on the company FAQ page.

Do BiSlides need lubrication and how often?

Lubrication is important for motor-driven systems or wherever you want maximum life and the lowest friction. BiSlide Assemblies should be lubricated with Velmex BL-1 oil. Only a few drops are required to keep your slide running smoothly. The load and hours of use effect the amount and frequency of lubrication. Manual BiSlide assemblies require less frequent lubrication. See the user guide that came with your BiSlide for recommendations.

Can BiSlides be mounted together?

Yes, BiSlides can be mounted together in XY, XZ, XYZ configurations. Mounting BiSlide assemblies in multi-axis systems is easy using cleats. T-slot bases and frames can be added for more structure and to create application specific systems. They also can be combined with Velmex Rotary Tables and our other linear stages to make custom systems for a wide range of requirements. See BiSlide Options and Accessories for more information on the cleats and T-slot structuring.

How are Parallel-Coupled BiSlides kept in synch?

The lead screw versions of a Parallel-Coupled system use a synchronized timing belt. While the Belt-Driven versions use a drive shaft coupling. The separators also help keep the base square and the two BiSlides parallel.

How do I mount a BiSlide to my working surface?

BiSlides typically are mounted to any surface with the BiSlide cleats. The surface should be flat to avoid binding, operate smoothly and accurately. Steel or aluminum are recommended for the surface. For heavy loads, you start with 2 pair of cleats (4) and add a pair for every 5" in travel. Lighter loads would require fewer cleats.

How do you adjust the carriage fit on an BSlide?

Adjustments the carriage on a BiSlide may be necessary after break in period and less frequently thereafter. The Lead Screw Nut (StabilNut) has an adjustable mesh to minimize backlash. Carriage fit can be adjusted by tightening the bolts on the carriage surface. See the BiSlide Owners Manual for how and when to adjust.

How much weight can you lift vertically with a BiSlide Belt driven slide?

When used with a Velmex VXM™ controller you can lift up to 20 lbs. with the Belt Drive model. However, when using a BiSlide® Belt driven slide mounted vertically it should be used in conjunction with a "Fail-Safe-Brake" option to prevent rapid dropping. A VXM™ with braking option is offered. A servo system with similar braking option can lift up to 40 lbs vertically on the Belt Drive.

How do I increase the resolution on the Belt-Driven BiSlides?

Gear reduction motors are available that will increase the resolution on a Belt-Driven BiSlide, however, that will reduce the travel speed.



If you have questions about your specific application or want us to design a Parallel-Coupled System for you, please complete the Request Assistance form or call Velmex to speak to one of our Application Engineers.