The BRIG Sim Racing Rig

Background.

Always had an interest in fast cars from: watching F1 Legends Mansell, Hill, Coultard, Haikonen, Raikkonen; having aspirations for building and racing my own Sports Car; to owning for a short period a Renault Clio Cup 173. Given time and financial constraints with the benefits of modern computing Sim Racing is a safer and more suitable outlet for my inner speed demon.

My first look at Sim Racing was in 2010 when my wife left me unsupervised for 10 days (Work Conference in the US) and I set up a TV/PC combo with F1 on Steam and a Logitech G27. Poor FOV and a rig that had more in kin with a torture device on ice I lost interest very quickly.

Fast forward to lockdown (June 2021) adventures in racing on the xBox with a Logitech G923 and Forza 4.

I was then very quickly persuaded and encouraged away from arcade racing to sim racing and this escalated to a full Rig with Direct Drive and a decent PC.

The Extrusion Rig (aka The Brig)

Traditionally a Brig is a two-masted sailing vessel and this sim-rig has the two dash masts from which the dash and screen are mounted. The word also referred to small warships popular amongst pirates due to their speed and manoeuvrability that carried up to18 guns. There are many occurrences of Brigs in popular fiction. The word can also refer to a prison but this relates to the use of Brigs as floating prisons.

The Build

The Brig is built from a Bosch Rexroth (BR) compatible extrusion produced by KJN in Leicester, UK. The extrusion comes with a 10mm slot. The following images are to scale and should show enough for anyone to replicate.

The following build of materials (BOM) covers what one would need to order from KJN (or alternative) to replicate.

Description	Type	Length	Qty
Side Member	120 x 40	1350	2
Cross Member	80 x 40	500	4
Front Pillars	80 x 40	200	2
Bulkhead Pillars	80 x 40	1200	2
Dash Cross Member	80 x 40	580	2
Seat Rails	40 x 40	540	2
Dash Rails	40 x 40	300	2
Pedal Rails (optional)	40 x 40		2

Description	Type	Qty
Right Angle Bracket	40 x 40	34 – 38
Tilting Bracket (with fixings)	40 x 40	8 – 12
T-Bolt & Nut	M8 x 20	100
T Nut	M8	10
End Cap	120 x 40	4
End Cap	80 x 40	6
End Cap	40 x 40	8 – 12

NOTES:

1. The variation in bracket numbers is due to availability. Ideally for the above set up you would orders the numbers in bold (34 & 12) but those for the dash can be swapped to normals. It is possible on the style I purchased to snap off the slot guide tabs for greater flexibility and this is necessary when the brackets are located across a slot.
2. The side rails could afford to be 50 – 150mm longer depending on space available and future plans. If you felt you might do a full motion rig it would be a wise addition I feel and if this was the case I would also add an additional cross member.
3. I didn’t use pedal rails as I have gone for a wood board. The board is 12mm Plywood (400mm x 500mm). I have read that wood provides better/nicer acoustic properties that I felt would improve the feel from the Base Shakers placed on the underside
4. The Dash is made from a piece of 20mm Oak (220mm x 1000mm) because it looks nice.

The Fit Out

Having used the following image as a guide for correct seating position and control arrangement I think it works well. Everything seems to be in the right place or close enough. And using the Modern FOV Calculator I seem to be able to get an acceptable FOV with a 50″ screen.

The Seat

I have successfully fitted a front seat from a Honda Civic Type R to the Brig. 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 Screen

For now, I am running a 50″ HISENSE 4K UHD HDR Smart TV and purchased a PERLESMITH Swivel Tilt TV Mount for the task of pairing it to the extrusion. It is mounted to the top slot of the lower dash cross member.

The Wheel

The wheel is clamped direct to the Oak Dash.

For the first few weeks I ran the old Logitech G293 which worked well although when hunting those last few tenths (or seconds) I felt I was lacking force in the wheel response and finesse in the pedals so I upgraded.

After some serious spread sheeting and much watching of the Sim Racing Garage reviews comparing different direct drives I opted for Simucube 2 Pro Direct Drive System – R2 with Ascher Racing F28-SC V2 Sim Racing Steering Wheel and Heusinkveld Engineering Sim Racing Sprint Pedals.

Sim Hub – Dash Studio

An old Pixel 2 is mounted across the wheel base using the AndrewFX Smartphone/Tablet stand for Logitech. I was able to modify it to fit the phone using the SCAD model kindly provided by Andrew. Andrew’s mount was not specifically designed for the G293 but it does fit, however, I think there is room for improvement around the knob turrets and across the top of the wheel base.

Sim Hub – Gear Indicator

Simhub provides many useful & cool features including a gear indicator. My design followed the guidance of AMStudio on YouTube and their video but I had to redesign the box unit due to variations in the MAX7219 8 x 8 Dot Matrix Display available and the attached header pins.