Fold-N-Go Magshock Armrest Hinge Washer

The Fold-N-Go is an amazing powered wheelchair.   The current, “Magshock,” model is capable of propelling up to 350 pounds of person at your typical powered wheelchair speeds for up to 17 miles range.  Certified for FAA use on skybridges to airplanes (Gate check the chair, sans the controller, and have it waiting for you at the end of the flight, ready to take you out of the plane.).  And a lot more, all weighing in at 50 total pounds weight.  

But this isn't really an advert for the chair.  This is about making a repair part for the thing.  All their parts are available in one way or another (you'll have to ask for this one- it's not on the store website…) but some of them are harder to lay hands on than others.  

The hinge washers/friction keepers for the armrests are one of the harder to lay hands on parts from the vendor.  

These are a pair that assemble into the hinge joints on the armrest assembly and perform the function of allowing it to slip just a little bit but yet provide holding friction as you fold the chair up for transport.  They're a wear item that, since we used it a LOT over a three year span, probably even more than the vendor even anticipated, wore out in ways they didn't envision. 

That being said, while they're a simple part, you would have to buy it from them, be able to injection mold the specific shape in question, or 3D print the right shape out of something like at least ASA/ABS for durability and environmental considerations.

To that end, I modeled the shape up based off of measurements of the badly worn part and the hinge itself.  This was to let me make these things at-will for my wife's wheelchair.

Print TWO of these for each armrest you're fixing.  The parts are expressly designed to let you assemble it right back together as if nothing had changed and it is basically factory “new”.  It will print in most materials, but since this is a travel chair, you probably want to print it in at least PETG (Update: PETG is sticky compared to the ASA and wears quickly) or ASA (I used ASA here…  It seems to be good enough for this use.  Nylon, despite what I say later here may well be the best- it's just that you may need to tighten a bit more to make it work… ).  Other materials might be good choices- but may have some tradeoffs involved with their use (Obviously).  You want limited lubricity as this is supposed to turn up and down, but hold it's specific position you leave it in (So, PA/Nylon's probably got more than the usual issues there, for example…).  Print this in 100 percent infill.  It's a wear part so you want to have maximum abrasion resistance and overall strength in these parts.

Once printed, it's a simple operation that the part will assemble on the hinge on each side of it and you just bolt it all back together.