A knee-lift bar is a hands-free mechanism (sometimes referred to as a FHS-free hand system) on some sewing machines that moves the presser foot up and down by moving your knee, it is not an item we sell.
The question regarding if you use a knee-lifter bar refers to the placement of your sewing machine on the platform (how far to the left/right and front/back does the machine need to sit on the platform). There are 1000s of sewing machines and they each have a different placement for the knee-lift bar, if you use this mechanism it is possible your custom insert will need special placement. The additional fee is a guarantee that the insert we create will not interfere with your use of the knee-lift bar on your sewing machine. Forgoing this charge and we cannot guarantee you can use your knee-lift bar on your sewing machine in the cabinet with the insert installed.
Below is an example of placement and how it will affect the use of your knee-lift bar in some instances:
In this example the sewing machine placement on the lift platform will prevent the knee-lift bar from being able to be inserted and used with your custom insert. The metal support bars for the lift platform are in the way of the knee-lift hole.
This photo shows the machine on the platform moved slightly to the left to accommodate the hole for the knee-lift bar-example of a custom placement for knee-lift accommodation:
Below are the 2 questions asked to determine if your set up needs special placement for the knee-lift accommodation:
Knee-lift placement for custom insert
The standard position of the machine in the cabinet opening from front to back is centered. Will this work for you? ___________ [Front dimension-red arrow]
(If no, please indicate in measurements of 1/16”-increments how far from the front of the opening to the front of the skinny free arm you wish to have your machine sit:__________)
The standard position of the machine from left to right is to have 1"-3” to the right of the machine to allow room for the machine to lower up and down on the lift. The gap allows room for the handwheel and cords that typically are located on the right of the machine. Will this work for you? _____________ [Left dimension-purple arrow]
(If NO, please indicate in 1/16”-increments how much space you will have between the left / tip of the free arm of the machine and the left of the cabinet opening: _________)