Are you completing an ultralight wheelchair order form and can’t figure out what a “frame offset” is? The good news is, you’re not alone.
There are many different mobility chair parts and measurements to know that ensure you get the most comfortable seat, with features that align with your lifestyle.
In our guide to ultralight ordering, we cover the manual wheelchair from top to bottom, so you can complete your order with peace of mind.
To kick off our guide, we’ll first look at how to measure the frame length. To get the most accurate measurement, start at the middle point of the backrest tube and follow it down to the front near the footrest extension tubes.
The frame positions the user’s body leg angle horizontally when sitting in the chair, so the frame length measures the distance from the heel of the foot to the back.
There are two common types of frame lengths:
So, for example, if a user is of average height and prefers a tucked leg position, they might go for a shot frame. On the contrary, a taller user might want to extend their legs and opt for a long frame.
Pro Tip: The form to order a wheelchair varies between manufacturers. You might see frame lengths labeled as short, medium, or long. Make sure to look at the footnotes on the form for measurement specifications, or you can always call the manufacturer directly.
When deciphering the best frame type for your needs, there are three main styles to choose from: swing-away, fixed, and tapered.
Before we explain what a front taper is, we’ll warn you that manufacturers have different definitions for what it is.
Some describe it as narrowing of the chair’s front by 4” starting with an 18” seat width that tapers down to 14” at the feet.
Others call the taper an “offset” where the footplate is offset by 2” inward from the edge of the seat, resulting in an 18” to 14” taper.
You might also see manufacturers defining the taper as the overall footplate width, as in a 14” taper on a chair with a width of 18”.
The steep part at the front of the chair where the seat tube travels down to the footplate is called the front frame angle.
When you order a wheelchair online, this might be measured from 60 to 85-degrees, dictating your footplate location and leg angle.
For reference, a 70-degree outside knee angle is commonly recommended as the most natural position. Of course, everyone is different, so you’ll want to experiment with the measurement using this as a good starting point.
As a rule of thumb, every 10-degrees equates to (+/ -) 1” in length. For example, if a 70-degree bend has a 23.5” frame length, an 80-degree bend shortens to a 22.5” frame length.
The seat width of a wheelchair varies depending on the manufacturer, so don’t feel bad if you get confused!
Here are three different scenarios you might see on your ultra light wheelchair order form.
Pro Tip: Before making a decision, confirm the points the manufacturer uses to measure the seat width.
This regards the measurement of the seat sling, which runs from the rear to the front of the upholstery. It’s essential to factor in a bit of extra space for a seat cushion.
Next up, we’re looking at the seat height, which is measured from the ground plane to the seat plane. This is also referred to as seat-to-floor height.
On custom manual wheelchairs, the size range is anywhere between 12” and 21”, depending on the model. For reference, adult ultralight manual wheelchairs range between 14” to 19” to transfer heights or make it easier to push comfortably.
When configuring the best measurement for you, remember to consider the seat cushion thickness, as this also adds some height.
When buying a custom wheelchair, there are three different types of leg rest/footplates to choose from. This includes flip-up, flip-up platform, angle-adjustable, and rigid/platform.
It’s also important to note that extension tubes are the mounting components that connect the footplate to the mounting frame. Take care to choose the correct length for your height, as this determines the size of the leg rests.
The backrest is measured from the top of the seat sling tube to the top of the backrest. On your custom lightweight wheelchair order form, it comes in adjustable packages that measure in 1” increments. For example, 12.5” to 15.5” is a range you might see.
Don’t forget the added height of the seat cushion when making your selection!
When it comes to the style of your backrest, there are three common designs, including folding. fixed, and angle adjustment.
Extra light wheelchairs feature rear wheels that angle so that the top of the wheel pulls toward the user’s body.
This is called the camber, and it provides more stability and adept responsiveness that makes it easier to push efficiently.
If you’re wondering how much camber is enough, here’s some food for thought:
Conventional wheelchairs typically sport 1-8-degrees of camber, with 3 to 6-degrees being the most common range on the marketplace.
When the camber runs higher than 8-degrees, this causes the chair to widen where the wheels meet the ground, making it a challenge to get through small doorways.
If you’re worried about the camber increasing the width of the chair too much, it’s best to contact the manufacturer to establish the best amount for your needs.
The axle plate connects to the rear wheels and is horizontally and vertically adjustable for a more precise center of gravity. This component also allows for the adjustment of the camber.
A camber tube is what connects the axle to the chair. Depending on the wheelchair model, this can be adjustable, too. This component covers the entire chair width, further streamlining performance.
An amputee axle plate is another type of setup which places the axle behind the backrest for improved stability.
The axle keeps your wheelchair in position, so you have complete control to move it about as you so desire.
Stainless steel is what you’ll commonly see on the market, with a quick-release button that allows for the wheel to slide off.
There is also the quad-release axle, which allows the user to remove the wheel with little effort. All you do is flip a lever, and it comes right off.
Titanium axles are stronger and weigh less, but are more expensive.
Ultra-lightweight folding wheelchairs have rear wheels that come in multiple sizes, including 20”, 22”, 24”, 25”, and 26”. Generally, 24” is the most common.
Choosing the right size is important, as the rear wheels determine the push stroke, roll rate, and seat-to-floor height.
The rear wheels can be comprised of a few different materials. Spoke wheels are light and fast, while composite wheels are heavier but highly durable.
On custom-made wheelchairs, handrims or “push rims” are tubular structures manufactured using aluminum, metal, or composite.
There are a few different finishes with different feels. Handrims can sport an anodized finish, which is smooth to the touch and durable.
Handrims can also be finished with a powder or vinyl coat, but these types tend to wear off over time.
There are also projection handrims, which are equipped with small nubs that give users a better grip to push.
There are two different types of projection handrims. The vertical variety rises from the handrim, while the oblique variety comes out from the side at a 45-degree angle.
The wheel locks are what keep a wheelchair from rolling away, whether stationary or not. Some models come with a grade aide, which prevents wheelchairs from rolling backward when traveling uphill.
There are three different types of wheel locks, including scissor lock, push-to-lock, and pull-to-lock.
The casters are the two small wheels located at the front of the wheelchair. They can swivel in any direction for easier maneuvering.
You’ll have to choose the size of your casters on your custom electric wheelchairs order form, which consists of 3″, 4″, 5″, 6″, 7″, and 8″ sizes.
Here are some things to look for on your order form regarding casters:
Custom power wheelchairs can have either tubular or removable armrests.
Tubular arms are tubes that are attached to sockets located behind the backrest. They’re lightweight and offer ample arm support, but not so much for the hips.
You can adjust the height on removable arms, and you get more hip support.
These panels keep your body parts, clothing, or cushion from falling out of the chair while you’re seated. It can be solid or made of fabric, whichever is most comfortable for you.
You might see some of these components pop up on your ultralight transport wheelchair order form. This is what they do…
Our guide on ultralight ordering is your foundation for navigating every little detail without any stress.
Remember, though, every manufacturer has different standards of production, so you’ll want to have their contact information nearby, just in case you need to clear up any confusion.
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