[Updated] Costco DPS Chair Silicone Lumbar Support Replacement

DPS Lumbar Support Replacement Part

=====================================

April 23, 2025 - Version 2 is now available!

Adjustments were made to the original model based on user suggestions and comments, changes include:

• Changed dimensions that allow for better fitment on the receiving caddy
• Removal of the metal plate required for structural support
• Increased height that minimizes movement between the locking bracket and this model
• Reduced screw posts making it easier to install without loosing part strength
• Wider holes for screwdriver passthrough, prevents bracket size constraints
• Increased bracket interface spacing to prevent part warping on install
• AND…
• 2 Different models for multiple situations or preference
  1. Regular: 42.40mm of distance giving a stock/factory feel
  2. Enhanced: 46.40mm of distance that pushes the support closer to your back (Recommended if lumbar support cushion is worn, old or flattening. A small increase that makes wonders)

As before, the following models require the metal retention brackets that allow the support to swivel properly like the original part. Models are already properly oriented to prevent the print from ripping itself apart over time due to the inherited flaw of printing in layers. Ensuring this replacement part to last as long or longer than the original silicone mechanism.

Suggested and Recommended Print Settings

The following settings are recommended for part longevity and strength:

• Layer Height: 0.2mm
• Wall Loops: 4
• Top Shell Layers: 4
• Bottom Shell Layers: 4
• Infill: Gyroid
• Infill Density: 10%
• Filament type: PLA, PETG, TPU, etc…

The following settings are suggested, they are to be taken in consideration if print fails due to overhangs, or bed adhesion. (These can be used for anything, not just this model) :

• Support Type: Normal (auto)
• Support Style: Grid
• Build Plate Only: True
• Top Z Distance: 0.15mm
• Bottom Z Distance: 0.2mm
• Base Pattern: Honeycomb
• Base Pattern Spacing: 3mm
• Top interface Layers: 3
• Bottom interface Layers: 1
• Interface Pattern: Rectilinear Interlaced
• Brim: 4mm Outer Only… OR Brim Ears

I hope this new model improves your chair even more compared to the previous model and also hope that it lasts for as long as the chair useful lifespan :)

Enjoy!

=====================================

Historical:  Version 1 Info

April 22, 2025: An updated model is in the works, the update will have better tolerances for caddy size discrepancies, reduced wear over time, better bracket post spacing, removal of the metal plate, optional increased distance for chairs which cushion is became flat over time, and improved print settings to prevent warping and increase part strength.

If you are here is probably because your lumbar silicone support is broken or is already starting to deform. Like many other users from Reddit, I also experienced this problem with a chair that was way past its warranty. Because it's a hassle to either take it back to Costco and Try to get it replaced, or even trying to contact manufacturer (with mixed results) and the fact that Costco from different countries have different warranty policies, i decided to instead fix the problem.

The following file is already properly oriented to prevent the print from ripping itself apart due to the inherited flaw of printing in layers. It's simple but its effective at replacing that part.

It requires the metal backplate and retention brackets that are inside the silicone part, the backplate is used to give it the necessary rigidity that will prevent the plastic to break from the base. Just place it before sliding the lumbar support with the new part attached. As for the brackets they can be fed trough the holes or  slide in place trough the posts. Use the original screws to put everything in place.

(Screws require a bit of force to get past the posts, this is intended)

Feel free to edit this part if needed or suggest edits to it and i will try to have them as soon as possible.

Print Settings

• Material: PLA
• Resolution: 0.2
• Infill: 15-20%
• Supports: No, but has overhangs - enable if prints fails.
• Brim: Yes - Outer 4mm Minimum - Prevent Warping
• Rafts: No

Picture by redditor in this post