Fitting A Mount Kit – Part 2: Parts for Fine Tuning

When a communication device, a laptop or a tablet is mounted on a wheelchair it makes sense that it must be correctly positioned for the person using the technology to access it best. Think how a text-to-speech device might be best operated, with access to the keyboard or on-screen keyboard normally requiring it to be closer to the person using it and maybe slightly above lap height.

This will be different for a device that is being accessed by switch scanning or via a head pointer system like Tracker Pro where access must be higher and further away from the user.

Again, how will this differ for people using eye-gaze access systems where the positional relationship of the eye-tracking camera to the person using it is specific and possibly even creating a competing need between communicating and driving the wheelchair.

Different needs may require different device positions which means the Mount Kit must be fine tuned to meet those needs. Two simple ways to make that happen are through the use of bends in tubing and specialised DAESSY parts. 

The DAESSY Mounting System is designed as component parts that come together as a whole to make a mounting kit.  As such, these components can provide methods of adjustment to allow for the correct positioning of a mounted device for best access, to avoid important immovable parts of the chair (like vehicle tie-downs) or to make sure the mount kit fits within the space around the chair for comfort and safety.


It’s no great mystery, the Tubes or Poles supplied in a DAESSY Mount Kit can help with the correct device height position by simply attaching the tube in the kit and extending or shortening it vertically at it’s attachment point, all done with an Allen key where they are fixed at the Frame Clamp Assembly. This is quite easy at the Removable Outer Piece (ROP) in the ROP variants or at the Index Clamp in the non-titling seat system kits. You can “tail” tube at of the bottom of these parts so that height is perfect, which can also leave room for growth in the future too, or with an ROP mount variant you can extend the tube to is maximum height by flushing the tube end to the bottom of the ROP part. If more height is needed than that supplied as standard, then consider longer tubes and also consider strengthening your kit if very long tubes are required for holding heavier devices.

The standard length tube supplied in most DAESSY Kits is 22″ (56cm), or 24″ (61cm) in the Rear Folding Mounts, which has been found to be enough length to fine tune for device height. You should have around 5 to 10 cm of height adjustment just through the length of the tube itself.

At the Frame Clamp Assembly, the tube length that protrudes below the frame clamp must be carefully considered so that it will not impede brakes, vehicle tie-downs or other items specific to the wheelchair, so a balancing act must be performed between the height needed for positioning of the device above the frame clamp, the amount of “tail” needed for future growth (if any) and avoidance of other wheelchair fittings below the frame clamp. If needed , shorter poles can arranged to avoid obstructing these important wheelchair features or functions; pole lengths are the easiest tool to use in your Mounting Toolbox.

S-Bend Vertical Tubes

The DAESSY S-tube is a length of stainless steel tube with a bend along it’s length which offset the ends of the tube but also keep them parallel. You can see how that works in the picture to the left.

Three measurements describe the S-tube:

  • L – The overall length
  • O – The offset distance
  • S – The straight length at one end – normally the shorter of the two ends.

S-Bent tubes can be reversed, generally there is no “up” or “down” with the tube.

The standard S-Tube supplied with the DAESSY Rigid Mount, DAESSY Folding Mount and DAESSY Swing-Aside Mount has the following dimensions: L = 22 inches, O = 3 inches, S = 4 inches. The part code for this S-Tube is S-22×3. If extra length is needed, it will need to be specified at ordering.

The DAESSY Rigid Mount, DAESSY Folding Mount and DAESSY Swing Aside Mount can be ordered with a custom sized S-Bent tube. The regular DAESSY Fitting Procedure should be followed to determine the dimensions of the custom S-Tube and Communicate AT prefer this to be indicated to use at the time of ordering by the L, O and S dimensions mentioned above. In that way we can ensure you get what you need

The minimum overall tube length L available is 14 inches. The minimum straight length S available is 3 inches. The minumum offset distance O available is 3 inches and the maximum offset is 10 inches. The accuracy of the lengths and offset distance on S-tubes is +/- 0.75 inch and any tubes longer that 28 inches must also consider a strengthening of the Frame Clamp Assembly using the alternative Angular DAESSY components.


The ends of the stainless steel tube provided by Daedalus Technologies, Inc. are fully machined and chamfered to minimize sharp edges. Communicate AT disapproves of the tube being cut to length after purchase. Cutting the stainless steel tube by any method produces very sharp and hazardous edges.

The DAESSY Rigid Mount, DAESSY Folding Mount and DAESSY Swing-Aside Mounts use a S-tube for positioning the mounted device. In addition to front-to-back positioning with these mounts the S-Tube can be aligned to place the upper end further sideways than the lower end to pass outside the edge of a tray or navigate around armrests. S-tube are a simple way to fit the best position of a mounted device

An S-Tube can also be used with the DAESSY Rear Folding Mount and DAESSY Lockable Rear Folding Mount to bring the upper end of the Side Tube outside the edge of a tray or to avoid other obstructions along the side of the wheelchair. In some mounting situations with the DAESSY Rear Folding Mount and DAESSY Lockable Rear Folding Mount it may be desirable to incorporate an S-bend in the Side Tube to clear an obstruction on the wheelchair during the rear folding motion. The details for specifying the tube length and s-bend dimension are the same in this circumstance.

S-bent Tubes and Offset Links combined with Frame Clamp Spacers can also be used to avoid the mount contacting other wheelchair fittings or obstructions to the folding motion.

Other Parts To Assist With Fine Tuning

Other than Tube, there are specific components that can also help with making your DAESSY Mount Kit fit the need perfectly.

Offset Links

The DAESSY Offset Link (O3L) and the DAESSY Single-Sided Offset Link (O3LS) are aluminum bars which provide 3 inches of separation between the Inner and Outer Frame Clamp components.

The Offset Link is connected to the other components with Swivel Clamps which allow the components to be held at any angle relative to each other. Two Offset Links can be attached together to provide up to 6 inches of offset between the Frame Clamp Inner Piece attached to the wheelchair and the Outer Piece of the Frame Clamp Assembly supporting the Vertical or Side Tube.

If more than 6 inches of offset is required it may be possible to combine Offset Links and S-bent Tubes, please contact Communicate AT for advice.

The Offset Link is 0.5 inch thick and moves the Frame Clamp Outer Piece further out from the wheelchair frame by this thickness. When the overall width of the wheelchair and attachments must be minimized the ‘single-sided’ Offset Link (O3LS) can be used as it turns the Frame Clamp Outer Piece back towards the chair. This creates a more compact Frame Clamp Assembly.

The adjoining faces of all the parts for a Frame Clamp Assembly have circular grooves to give extra friction against movement when assembled. The grooves on an Inner Piece engage with the grooves on an Outer Piece but will not engage with the grooves on another Inner Piece. Offset Links and Frame Clamp Spacers have the letters IP stamped into the metal beside the grooves that attach to the Inner Piece and OP stamped into the metal beside the grooves that attach to the Outer Piece.


All the grooved faces must be correctly matched and engaged before the Swivel Clamp bolts are tightened. When the grooved faces are correctly matched it will be possible to turn the mated components in a circle, but they will not slide across each other at the grooved face.

Offset Links – Helpful With “two chairs, one-mount” Scenarios

The Offset Link can be used with the DAESSY Rigid or Mini Rigid Mount, DAESSY Folding or Mini Folding Mount, DAESSY Swing Aside or Mini Swing Aside Mount, DAESSY Mini Adjustable Mount or DAESSY Positioner Mount to adjust the fit of the same mounting assembly on two different wheelchairs.

When a mounting assembly will be used on two wheelchairs and the fitting measurements differ between the two chairs the Frame Clamp Outer Piece may be relocated relative to the inner piece on either or both chairs to correctly position the mounted device on both chairs.

Frame Clamp Spacers

Two types of Frame Clamp Spacer are available. The standard Frame Clamp Spacer (UFCSPCR) is 0.75 inch thick and provides this separation between outer and inner components of a Frame Clamp Assembly. This clearance may be necessary to avoid obstructions such as the rear wheel or brake levers or to allow the lock of the Removable Frame Clamp Receiver to turn if it’s tight against a seat cushion.

The Right Angle Frame Clamp Spacer (UFC90) changes the plane of the Frame Clamp components by 90 degrees. This may be necessary if the only available location for the Frame Clamp Inner Piece is on a cross-tube perpendicular to the side of the wheelchair.

Together or separately, the DAESSY S-Bend Tube, DAESSY Offset Link and DAESSY Frame Clamp Spacer can fine tube the Frame Clamp Assembly and allow for more accuracy and positioning convenience at the device. This helps with making the mounted technology all the more accessible