Sailrite® WorkerB® Power Pack Motor System (110V)
SKU: 122891
20 Available


Upgrade your Ultrafeed® Sewing Machine to the WorkerB® Power Pack and experience unrivaled power and control like never before. If you feel like your machine sews too fast and you want to sew with slow stitch-by-stitch speed, you need the WorkerB. If your sewing machine has ever struggled to push through dense assemblies, you need the WorkerB. With the WorkerB, your sewing experience will never be the same.

The WorkerB Power Pack offers the best of both worlds: unprecedented power and the portability you need for your Ultrafeed machine. The WorkerB is an innovative portable motor system never seen before in the sewing machine industry – and it’s found only at Sailrite.

How Does the WorkerB Compare to the Original Ultrafeed Motor?

  • Power: The most powerful motor designed for portable sewing machines, the WorkerB boasts 2.5 times the power of other portable motors. More power, more control – even through the hardest materials.
  • Speed Control: Easily adjust the maximum sewing speed with the dial on the control box. Whether your comfort level is stitch-by-stitch precision or 638 stitches per minute, the WorkerB provides maximum power at any speed. Scroll below and watch our video to see the speed control in action!
  • Power Boosting Technology: When the machine encounters resistance from changes in fabric thickness or density, the control box provides a boost in torque to power through.
  • Integrated Light Outlet: Conveniently plug the Flex20 LED Light right into the control box. No need to hunt for an extension cord or available outlet.
  • On/Off Switch: Shut the motor off with the machine plugged in. If the foot pedal is accidentally pressed, the machine won’t run and the needle won’t move. This is a great safety feature if you have small children or pets.
  • Balance Wheel: The ergonomic hand grip makes it easier to operate the machine by hand.
  • Foot Control Pedal: A large range of pedal movement provides unrivaled slow speed acceleration.
  • Quieter Operation: The WorkerB is a quiet motor without the low-speed whine from a standard portable motor.

Is the WorkerB a Rebranded Motor System?

Definitely not. The WorkerB Power Pack is a Sailrite-exclusive design two years in the making. We partnered with a well-known power tool manufacturer to engineer the proprietary circuitry. Our mission was to ensure each system met our standards for speed, power and portability.

Will the WorkerB Power Pack Work on My Older Ultrafeed?

An important part of our design phase was making sure the WorkerB would be compatible with every Ultrafeed Sewing Machine – no matter how long ago you purchased yours. If you own a Sailrite Ultrafeed, the WorkerB Power Pack will work on your machine.

Note: Not only is the WorkerB Power Pack compatible with the Posi-Pin® Safety Shear, but it also works with older friction clutches.

Does the WorkerB Work With Other Balance Wheels?

The WorkerB Power Pack is compatible with other Ultrafeed balance wheels. You can use the WorkerB with the Monster® II and Power Plus® Balance Wheels for even greater slow speed control. The larger-size belt diameter of these balance wheels acts as a further gear change, allowing you to experience finite control of stitch-by-stitch placement and needle positioning. This is an excellent feature for leatherworkers and anyone who wants the ultimate in slow speed control. Simply remove the WorkerB Balance Wheel and the 13-inch belt and replace them with either the Monster II or Power Plus Balance Wheel and an 18.6-inch belt.

A Note About the Integrated Light Outlet: Electrical items exceeding 100 watts should not be used in the control box outlet. Exceeding this limit may blow the control box fuse.

WARNING: Always plug the WorkerB cord into a grounded outlet and do not use an adapter without a ground pin. We do not recommend the use of long extension cords to plug in the WorkerB Power Pack.

Please Note: WorkerB Power Packs are designed to work on inverters/generators of 400W or more of the Modified Sine Wave or Square Wave types. Pure (or Digital Synthesized Wave) Inverters/generators can disrupt the “phase cutting” technology of the WorkerB since they hide high-frequency current in the waveform.

The WorkerB® Power Pack Includes:

  • WorkerB® Motor 90VDC
  • WorkerB® Motor Control Box 110V
  • WorkerB® Balance Wheel
  • WorkerB® Foot Control
  • 12 Tooth Cogged Motor Pulley
  • Cogged Timing Belt 13"
  • Belt Cover
  • WorkerB® Bracket
  • WorkerB® Power Cord
  • Combo Wrench and Various Screws
  • Two-year limited warranty


Sale Unit: EA
Machine Series: Ultrafeed LS-1, Ultrafeed LSZ-1
Sewing Speed: 304 stitches/minute (with Monster II Balance Wheel), 638 stitches/minute (with WorkerB Balance Wheel)
Power: 90VDC, 1/4 hp, 3 amps
Motor RPM: 5,800
Brand: Sailrite
Horsepower: 1/4
Input Watts: 375
Output Watts: 350 (Max.)
Motor Amperage: 0.38 (Starting); 3 (Max.)
Input Voltage: 110V A.C.
Motor System Weight: 6.65 lbs.
Sewing Speed with WorkerB Balance Wheel: Stitch by stitch up to 638 stitches per minute
Sewing Speed with Monster II and Power Plus Balance Wheels*: Super slow stitch by stitch up to 304 stitches per minute
On-Off Switch: Built-In
Warranty: 2 Years
*Monster II and Power Plus Balance Wheels are not included with the WorkerB Power Pack Motor System.


WorkerB® Power Pack Motor System Demo

WorkerB® Power Pack Assembly & Installation

WorkerB® Power Pack Slow Speed Control Demo

Modifying Your Older Ultrafeed® Carrying Case for the WorkerB® Power Pack

If you own the older Deluxe Ultrafeed case or the older Industrial case (2016-2017), the new WorkerB Power Pack will fit in your case with some slight modifications to the foam padding. The gray case that predates the Deluxe case fits with the WorkerB without any modifications.


Overall Rating : 4.98 46 Reviews

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Verified Purchase

Now I'm ready to tackle some projects I was procrastinating on beginning!

What's not to like? The advantage of dialing down the speed to a snail's pace makes possible precisely placed stitches with ease! It makes having to remove mistakes like crooked run-away stitches a thing of the past!

James Garetson
Verified Purchase

Great for leather

Slows down the machine to get the power and precision I needed to sew leather. Great upgrade!

Kimberly Smith
Verified Purchase

I love the extra power and the ability to slow down and control my machine.

Lance Whaley
Verified Purchase

Paint control box or add correction to set up video

Jeff G.
Verified Purchase

Awesome upgrade to this machine. Would be nice if they were built with this motor.

Walt Fuller
Verified Purchase

This is going to be a great help and allow better control for my novice stitches.

Verified Purchase

Great Addition

This addition to the machine allows me as a learner to slow down the stitching to make sure that I have the best chance of learning to sew correctly.

Jamie Ridpath
Verified Purchase

This such an improvement over the stock motor and thank you soooo much for have the instructional video on how to install it. Made a daunting task easy.

Jeffrey Byrne
Verified Purchase

Install went very smoothly. I like h addition of an outlet (which I use for a light)

Lynn Moline
Verified Purchase

Love my WorkerB!

Absolutely love my new WorkerB. Gives me so much more control!

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