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SchadenFred

BUILD THREAD: Frederic's budget sim rig

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Like all insane projects, this one started innocently enough.  I wanted to try out sim racing, in the hopes that I could get faster on the track.  But a sim just isn't in my budget right now.

I needed a new PC for work.  As I built it, it was easy enough to give it a video card that would let it run a simulator some day.  That's a justifiable expense, right?

 

Then Black Friday happened, and I picked up three Dell 22" monitors for $99 each.  I needed a triple monitor setup anyway for work, right?

 

A month later a used G27 came up for sale on Craigslist for a price that I couldn't ignore.  So I had to get that, right?

 

Shortly after, I checked prices on Assetto Corsa, and found that it was inexpensive enough to justify the cost.  Plus, I needed to try out the new G27 and make sure it worked, right?

 

Then iRacing went on sale, $99 for a two year subscription.  That's a great deal, right?

But despite all of this, I just can't justify a sim rig.  I got a good deal on some of the items.  I could build a stand and seat, but I have no place to put them.  Plus, the PC and monitors are needed for work, and so they have to stay at my desk. 

So here's the challenge.  Find a way to convert this desk and chair into a racing sim, without taking away from the functionality of the office.  And do it without spending money unless absolutely necessary.

 

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Problem one.  The office chair rolls quite well on my plywood "chair mat".  I need a way to lock the wheels.  I decided to keep it simple and make a set of wooden chocks.  A couple of wooden wedges would have done the job.  But because I like to overcomplicate things, I decided to use my CAD/CAM skills.

Step 1:  Model the shape of the wheel in Calibre.  The extra challenge is that I removed one of the wheels in order to measure it, so I did my CAD work while sitting in a chair that wanted to tip over.

 

5a4c2296ef0e1_20180102_18h23_19.png

 

Step 2:  Program the toolpath in SprutCam

 

5a4c22d45e091_20180102_18h24_40.png

 

Step 3:  Machine the pocket in some scrap wood.  Repeat 4 more times.



The result of two hours of programming and 30 minutes of CNC work is a non-rolly office chair.

 

5a4c254ec1605_20180102_182945.jpg

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Very interesting, I am thinking of making a sim rig myself, so I'll be following along to get some ideas.  Wouldn't it have been possible to just remove the 5 wheels for when you want to use it for sim racing, and install them back for when using it for work?  I wouldn't think it would take much longer than installing the wheel chocks themselves.

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That picture doesn't show it but the chair's gas cylinder sticks down a couple of inches below the spider. If the wheels are removed the chair turns into a teeter totter.:)

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That picture doesn't show it but the chair's gas cylinder sticks down a couple of inches below the spider. If the wheels are removed the chair turns into a teeter totter.:)

 

I'd call it a full motion sim rig at that point.

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That picture doesn't show it but the chair's gas cylinder sticks down a couple of inches below the spider. If the wheels are removed the chair turns into a teeter totter.:)

 

Simple solution - ask me how I know....but you can drag that chair (and a buddy) using a tow rope behind a vehicle on the street...it's all fun n games until the wheels grind themselves down to the nubs....makes going around corners a REAL challenge!! Oh yeah, helmet, gloves, elbow pads and knee pads HIGHLY recommended!!

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Reminds me of the story where the the US Space Program in the 60's spent millions inventing the ball point pen that would work in zero gravity.

 

The Russians used

 

 

 

 

a pencil.

 

Mike

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Reminds me of the story where the the US Space Program in the 60's spent millions inventing the ball point pen that would work in zero gravity.

 

The Russians used

 

 

 

 

a pencil.

 

Mike

 

 

And they had issues with lead shorting out all sorts of shit, broken pencil bits posed a safety issue.  they weren't being clever they were being cheap. 

 

 

Fisher was the one who made the investment for the development of the pens btw not NASA.  

 

Also with the availability of these pens the Russians used the same ones from Fisher. 

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Just build one out of wood.  Mine is based on the Ricmotech, but I didn't buy their plans.  I basically just looked at a bunch of pictures and winged it.

 

hPw3w9Dl.jpg

7cZlumyl.jpg

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Just build one out of wood.

Good looking rig!

 

I'd love something like this, but I don't have any place to put it.  And the computer and monitors are for work first, so they have to stay at my desk.

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I've got one of these: https://www.amazon.com/gp/product/B004AYM96A/ref=oh_aui_search_detailpage?ie=UTF8&psc=1with an old ass Logitech Driving Force Pro attached to it that you're welcome to have if you want.

 

It worked well for me when i used it at a desk like you have your setup.  Makes setup/teardown a lot faster and you can get the positioning just where you want it for the wheel.  I was lucky to pick up a full rig setup for cheap off of a TJ member who was moving a while back, so this has just been sitting around taking up space.  You'd have to rig up an adapter to get the G27 to mount to it.

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I've got one of these: https://www.amazon.com/gp/product/B004AYM96A/ref=oh_aui_search_detailpage?ie=UTF8&psc=1with an old ass Logitech Driving Force Pro attached to it that you're welcome to have if you want.

 

It worked well for me when i used it at a desk like you have your setup.  Makes setup/teardown a lot faster and you can get the positioning just where you want it for the wheel.  I was lucky to pick up a full rig setup for cheap off of a TJ member who was moving a while back, so this has just been sitting around taking up space.  You'd have to rig up an adapter to get the G27 to mount to it.

 

thats what i use (a G27/29 compatible one)    more or less happy with it and just sit on a metal folding chair. 

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why do you have plastic on your chair? do you pee a lot? 

 

For those "Oh CRAP!!" moments.... :tongue:  :tongue:  :tongue:

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I've got one of these: https://www.amazon.com/gp/product/B004AYM96A/ref=oh_aui_search_detailpage?ie=UTF8&psc=1with an old ass Logitech Driving Force Pro attached to it that you're welcome to have if you want.

Thank you Josh, that's very kind.  I'm going to decline your offer.  Before I started this thread, I'd been working on the rig on and off for a week.  I've got a solution about 90% completed.  I haven't posted about it yet, but I think it's going to work nicely.

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Thank you Josh, that's very kind.  I'm going to decline your offer.  Before I started this thread, I'd been working on the rig on and off for a week.  I've got a solution about 90% completed.  I haven't posted about it yet, but I think it's going to work nicely.

No problem, I’ll throw it up on the for sale forum for a 6 pack.

 

I’m interested to see what you come up with, hopefully it’s more CNC’d 3D contoured plywood :-)

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I mentioned earlier that I got a great deal on three Dell monitors.  $99 each on Black Friday.

But they had two problems.  The first is that they only had VGA and HDMI ports.  But my video card has a single HDMI port and three DisplayPort connections.
I solved this issue by buying some of these cables that convert DisplayPort to HDMI.  They work nicely so far.
https://www.amazon.com/gp/product/B0743D22JG/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

 

The other problem is that these monitors don't have VESA mounting holes on the back.  I want VESA mounts so that I can put the monitors on a single stand, and adjust their height, angle, and position with ease.  Here's the stand I chose.
https://www.amazon.com/gp/product/B01HSJX1FG/ref=oh_aui_detailpage_o00_s03?ie=UTF8&psc=1

This guy had one solution that seemed good.

 

I modified one of the bases according to his instructions.  But I didn't like the result.  It was ugly.  And his solution didn't let you rotate the monitor to vertical position, something I like to do when reading a long wall of text.  Or writing one, as I'm doing now.

(As I wrote that, I just realized that since I'm done with this work, I can rotate the monitor to vertical.  Ahhh, that's much better!)

To allow a monitor to rotate, the VESA mount needs to be in the center of the monitor.  To do that, holes must be drilled.  So let's void some warranties!

 

The victim, a Dell SE2417HG

5a52c608ddbc6_001MonitorBefore.jpg

Remove the stand from the monitor.  Remove the two screws that hold the monitor's case together.

 

5a52c6355eb55_002Removetwoscrews.jpg
 

Turn the monitor face down, and starting at a corner, use a trim tool to split the cases.
5a52c686357c6_003Splitcase.jpg
 

Spend an hour studying the insides of the monitor and the structure of the case to determine where you can put some bolts without shorting anything out.  I settled on the 100MM VESA pattern.  After a lot of boring measuring, marking, double checking, and measuring a third time, I marked and drilled two holes.

 

5a52c7a882a2e_Drilledholes.jpg

 

The back of the monitor is angled.  I want the VESA mount to be coplanar with the screen, so that when I rotate the screen to vertical, the angle of the screen doesn't change.  Luckily the stand came with some spacers for monitors with recessed VESA holes.  I modified them with a bench grinder and a file to put an angle on one end. Then I bolted the VESA mount on using the two holes I'd drilled, put the spacers in place, and used the mount as a guide to drill the remaining two holes.

 

5a52c86f81900_AngledSpacers.jpg

 

Then it was just a matter of tightening the bolts, snapping the monitor back together, and installing the two screws that hold it in one piece.

Then I modified the other two monitors in the same way.  It was easer to do the other two, because Dell had been nice enough to put a logo on the back of the monitor.  Instead of all that measuring, I just aligned each VESA bracket with the logo, then marked the bottom two holes using the bracket as a guide.

5a52c92098a7e_Aligningbracket.jpg

 

I drilled the bottom holes, bolted the bracket on, added the spacers, and drilled the top two holes.  Tighten everything up, reassemble the monitor, and move on to the third one.

After that job, putting the monitors on the stand was child's play.  The only downside to the whole thing is that if I put the monitors too far foward on the stand (in iRacing wraparound mode) the stand falls forward.  I'll be voiding the warranty on the stand to solve this problem.  Stay tuned.

For pictures of the completed setup, see my next post, coming shortly!

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Here's the challenge.  Attach the G27's wheel and shifter to this desk.  This should be simple.  The G27 is meant to clamp to a desk.
The problem is that this desk is a bit unique.  It's an old door, and it's about four inches thick.  The G27's desk clamps can't open that far

 

5a52bf1c19e0f_Desk.jpg

 

If you look closely at this picture, you can see that I'm using a CAD program to model the layout of my car, and then attempting to recreate the same setup at my desk.  I determined that this cannot be done, because my knees would wind up sharing space with the desk.  Tall Guy In A Miata problems.

Since this desk was originally a door, it's not meant to sit sideways with its span unsupported.  The builder solved this problem by adding a length of angle iron underneath.  Actually, he used two, and overlapped them with some bolts to hold them together.  I removed the two pieces, welded them together to make a single beam, and then drilled a lot of holes in it.  The holes are 3/4" and spaced 3" apart.

 

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With that done, I cut up some 3/4" allthread and put it on the lathe, to make these.  I left a smooth bit on the ends so that I would be able to thread the nuts on easily..
 

5a52c07989b88_Studs.jpg

 

 

Some welding was done.

5a52c0b32b864_StudsWelded.jpg

 

And then some more welding happened, to make a shifter mount.

 

5a52c0e6b38ad_Shiftermount.jpg

 

Followed by even more welding, to make a steering wheel mount.  Extra holes were drilled for lightness.  Yeah, that's it.  I definitely didn't drill two holes in a place that would interfere with the wheel's clamps.

 

5a52c1151d96e_Wheelmount.jpg

 

The wheel clamped onto its mount, but wasn't rigid enough.  So I added a plate to the mount to support the body of the wheel.  I didn't have a piece of steel plate handy, but I had some aluminum left over from another project.  This meant that I had to bolt it on rather than welding it.  It worked OK despite a couple of mistakes while drilling the mounting holes.

 

And then I painted everything.  The two screws go into the wheel from the bottom, holding it in place.  The wheel's clamps at the rear also hold it down.

 

5a52c2107d50e_Paintedmounts.jpg

 

 

With the G27 mounted up, here's the result.

I don't even need a wrench.  Tightening the 3/4" nuts to finger tight is enough to firmly hold the wheel and shifter in place.

 

5a52c2bf33af3_Deskplay.jpg

 

When it's time to work, I remove the G27, move the monitors back, put the keyboard back in place, and remove the chocks from the chair.  This takes less than 10 minutes.

#CATTAX

5a52c36d0bef4_Deskwork.jpg


Total cost for this mod:  $0.  I had everything I needed collecting dust in the garage!

So, what's left?

Add a load cell to the brake pedal.
Disassemble the pedals and mount them in a hanging position, in the same configuration that I have in my Miata.
Stop crashing on Laguna Seca.  (This keeps happening!)

 

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Last night the G27 got an upgrade.  I bought and installed a Ricmotech load cell.  This is a clever little gadget that replaces the potentiometer on the brake pedal, turning the pedal from "Sweet Jesus I Need To Bleed My Brakes" into "This Feels Like My Miata With Fresh Pads, Rotors, and Stainless Lines"

The installation was a snap, requiring only an allen wrench, screwdriver, and 3/16" drill bit.  The cost was $127.

 

If you're in the market for a new set of pedals, you're better off getting the Fanatec CSL Elites, which come with a load cell and have a higher resolution, for $200.  But if you already have a pedal set, then this upgrade is worth considering.

Calibrating the load cell is a little tricky.  Out of the box, it takes 70lbs of force to fully engage the brakes.  That feels excessive to me, so I adjusted it.  In iRacing I calibrated the brake pedal, and when "fully applying the brake" I approximated the force that would cause the wheels on my Miata to lock up.  The result of this is that the brakes are more sensitive at low pressure, and I don't have to be a gorilla on the pedal to brake for the turn.  It feels a lot like my Miata.

I also figured out why I kept crashing in turns 8 and 11.  iRacing has a bug (probably well known to everyone but me).  If the driver's arms are displayed, the on-screen wheel won't turn more than 90 degrees.  Any steering input from your actual wheel beyond 90 degrees is ignored.  This makes it impossible to take tight corners.  Once I got that sorted out, it was like having a whole new car!

Next on the to-do list is to build a new frame for the pedals.  I'm using the carpet hooks on the bottom of the pedal pack, but they're not up to the job now that I'm using the load cell.  I'll be taking the pedals apart and hanging them upside down instead.  And I'll do my best to replicate the layout and position in the Miata.

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