The Sim Racing Rig

This extrusion rig is built from a Bosch Rexroth (BR) compatible extrusion produced by KJN in Leicester, UK. The extrusion comes with a 10mm slot. I was replacing a wooden rig that didn’t allow for much adjustability – extrusion excels in this aspect and is a near perfect material for building your own sim-rig

Version 1 was designed around Logitech G923 pedals and after a later upgrade to Heusinkveld Sprint Pedals when I decided to flip my pedals in order to improve access to the mounting bolts I added the longer front uprights with some horizontal supports (Version 2). The final step was to add a support on the side for gearbox/handbrake mounts (Version 3). At the same time I changed the way the dash mounts were done for a cleaner design.

Version 3


The following build of materials (BOM) is for Version 3 and covers what one would need to order from KJN (or alternative) to replicate the rig. Download a PDF Drawing here.

Extrusion Cutting List

SMSide Member120 x 4013502
FPPFront Pedal Pillars80 x 405002
BPBulkhead Pillars80 x 4012002
CMCross Members (between SMs & FPPs)80 x 405005
DCMDash Cross Member (between BP)80 x 405802
DRDash Rails40 x 406002
SRSeat Rails40 x 405402
SDRSide Dash Rail80 x 408001
SDRSSide Dash Rail Support40 x 403601

Connection Elements

Right Angle Bracket40 x 4049
Tilting Bracket (with fixings)40 x 404
T-Bolt & Nut (2 / Bracket)M8 x 20106
T Nut (Pedal Board, Dash and Seat Rails plus some extras)M820
End Cap120 x 404
End Cap80 x 405
End Cap40 x 406

Driver Positioning and FOV

The following image as a guide for correct seating position and control arrangement. Everything seems to be in the right place or close enough and there is plenty of adjustment. With the Modern FOV Calculator I was able to get an acceptable FOV with a 50″ screen.

IMAGE CREDITS: Cosy Racing Community

The Seat

I have fitted a front seat from a Honda Civic Type R to the rig. The original mount brackets were ground off and the rivet holes left increased to 8.5mm. This allowed M8x12mm bolts with T-Nuts to be used to secure the seat to the seat rails. Note: This is an early picture and I later adjusted the seat so it sat ~5mm from the end of the rails not the ~100mm as shown as this gave better leg length range.


The dash is made from a piece of Oak although other most other woods would work. Its 20mm x 770mm x 240mm and this zip file contains a PDF of the drawing and a DXF.

Pedal Flip Upgrade

In order to flip the Heusinkveld Sprint Pedals a small shim was required to attach the back bolts. You can download it from Printables.

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