Robbie GRM+ Memberand SuperDork
11/30/15 2:01 p.m.

Here is a full build in a single post for those of you who suffer from forum ADD like I do. I took one of the seats out of my most recent challenge build, and converted it into an awesome office chair.

  1. I had been sitting at a folding chair at my home desk (and I work at home, so I had been sitting in a folding chair A LOT).
  2. I wanted the luxury of fine german car leather, arm rests, power-adjustability, and heated seats.

Here's the seat I removed from the challenge car:

Next I disassembled the two halves (while my son was napping, thanks baby monitor!):

Pull the foam and leather back on:

Each front seat has one armrest, but the metal frame happens to be the same for both seats so I was able to bolt both armrests to one seat (SCORE!). Then I needed to modify the map pocket and back cover a bit to accomodate:

Here it is in place:

And re-mated with the base:

Next I bolted a couple 2x4s to the bottom, thank goodness this seat mounts to a very flat floor so it was easy:

And finally I added an HF dolly to the bottom for wheels. I love HF dollies. Yes this is crude. No I don't care. It has wheels now, OK?

Next I needed power. This old computer adapter for a laptop we no longer have converts wall AC to 18.5 VDC at 3.5 amps max. Not perfect, but close.

The original heated seat circuit is AWESOME (on low setting the bottom and back heaters - about 10 ohms each - are in SERIES, and on high they are in PARALLEL - genius!), but they did use a relay and wiring to protect the switch that I had already hacked out of the seat during the challenge build - oops. So I added my own switch, and since the voltage is a bit higher than a car, I chose to hard wire the heaters in series. Here's the switch:

Next I cleaned up the rest of the wiring and used a spare 3M adhesive to hold the power brick to the chair (the cord from the wall to the chair does unplug at the power brick here if needed).


I don't have a picture specifically, but I remounted all the plastic to the bottom of the seat, including the stock adjustment switches. I left the seat belt receptacle for good measure too. Now I have a seat that is warm, rolls around, is comfy, has power adjustability, and needs a bit of a cleaning! Less than $20 spend too - because I had almost everything lying around.

After sitting in it for half the day so far, the heat is nice but it is still too hot. I may try to add a power resistor or potentiometer down the line. Today I have just been manually switching it on and off.

Finally, the Mr. Money Mustaches out there might be thinking about all the power I am using up just heating my own butt. However, I think this is a good trade. In general, we keep our house pretty low on heat in the winter - 65 ish. Then, we use space heaters in the basement office when it is too cold just in there. That space heater is 1500W, and my heated chair is 65W or less (that is the laptop brick - I calculate the chair uses about 18W actually). That is a WIN! I could just wear more clothes I guess, but that is no fun.

JohnRW1621 MegaDork
11/30/15 6:46 p.m.


YoloRX7 New Reader
11/30/15 11:37 p.m.


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