Hoddem's Aluminum Rig V2 (3-DOF, SFX, VR)

I needed to cut the 4x3x1/4" aluminum angle and while I know that my chop saw could do it as is, I felt that this was as good of opportunity as ever to buy a blade designed for cutting aluminum.

On the left is the blade that came with my saw, I use it for just about everything except finish work. It has probably cut several hundred cuts in aluminum extrusion. The new blade is on the right, it set me back a fair amount.



all I can say is WOW! I wish I had invested in this blade years ago, it cuts through aluminum plate like butter and it is so much quieter too. my only real complaint is that it turns the chips into dust so cleanup is a bit more of a concern.




I cut my angle to length and nicked the corners off. I also cut up some 1/4" plate to act as feet.



Next I laid out all the hole locations and then drilled a lot of holes, exactly 99 of them.
I had to rig up a special jig to hold the angle in a way that I could drill from the flat side.



I did a quick sanity check before finishing the remaining parts.



After drilling everything, I spent another hour or so cleaning everything up with a sander.



Back to the bathtub for a wash.

Finished parts all clean and ready for assembly.

I started assembly by first disassembling my simulator. I had to disconnect all of the electronics and then pull the actuators back off. I was joking to my buddy that it looks like my ride got jacked with it up on blocks.



I started to assemble the first actuator and quickly realized that I wasn't happy with how it was going.



I am trying to be extra careful here to align everything because I know that any skew will result in amplified problems later. The actuator needs to be as vertical as possible or else as it goes up and down the distance between actuators will change this will be in addition to the already discussed change in distance relative to the platform. Ultimately I was not happy with how the first one went together and I came up with a setup fixture.



still not completely satisfied I added a square reference.






I was satisfied with the new assembly method and I was finally able to mount the first actuator to the control box.








rinse and repeat for the remaining two actuators.



With the help of my wife I was able to get the base set in its semi final resting place. I will be moving up against the wall, but will leave it here until all of the wiring is completed. by design It just barely fits on my 4x6 mat.



Now I had to switch gears and focus on the rig. I needed to add the extrusion that the actuators will push on.
I am a little short on pictures for this part.

I had to remove the front and rear cross members from the frame, not to big of a deal, but not exactly easy either.


They needed to be drilled for the hidden fasteners that will hold the new extrusion assemblies.



Assembly of the front, again all hidden fasteners.



rear assembly is identical except the top member extends 9" on either side.







It looks pretty funky on the ground, I was able to convince a neighbor to help me throw it up on the box. It is pretty heavy, but manageable for 2 guys.







The rig is just sitting on the actuators right now, I have some cups printing now that I will throw on to keep it from accidentally sliding off. Overall I am pretty happy with the results. I may need to add some reinforcing plates/brackets depending on how much flex I get.

I need to fit all of this into my new enclosure.



I decided to ditch the computer case and go open air with my simulator PC. I picked up a frame kit off amazon and after a month of transit time it showed up at just the right time.

It doesn't look like much, but it is actually pretty well thought out.



Here is the old case stuffed with all sorts of out dated tech. FYI I am planning on upgrading to essentially a new computer once the AMD, INTEL and NVIDIA new release craziness is over. also I will be getting a reverb G2 or index at the same time, depending on how the reviews turn out for sim racing specifically.





After gutting the old pc



ready for the scrap yard



Here is the final configuration for my new open air PC, I removed all but the essentials. I still need to make some 3d printed parts to stack the two hard drives, but all in all it ended up pretty good.









My next big task is to move all of my electronics into the new box and begin wiring everything again. That will include a new relay bank and new control panel with switches to turn everything on as well as the red/yellow/green buttons for the motor controller.

A pleasure seeing all the attention to detail and craftsmanship. Looking forward to reports back on the actuator setup as this is something I want to do with my rig too.

@cfischer, @noorbeast

Thanks Guys, I honestly do enjoy the building process as much or more then the actual racing. This has been a pretty time consuming phase of the project though and I am very much looking forward to being able to do some racing.

my favorite part: ignition ramp!



your place is so clean and tidy! respect!

Thanks, the idea was that you could get in the simulator and start everything right from the seat. Plus the cool factor when you are booting everything up is level 10.

Also I do my best with the garage, the biggest challenge is keeping stuff from accumulating.

Holy crap time flies, almost a year later and no progress at all on this. Ive had this 90% complete system just sitting under a cover for way to long. I Have a few bigger projects I want to do over the winter and I am committed to getting this thing done so I can free up space in the garage.

Here is where I am at.

After I finished building the electronics enclosure/base I ended up making some 3D Printed cups with TPU inserts to allow for some movement due to the geometry changes when the actuators are moving.









So far in my limited testing they work well, I went through several design iterations on the TPU part and found this last design to be the best. Also I no longer have to worry about the upper frame sliding off of the lower frame. I will also add some limiter straps at some point so that the upper frame is mechanically connected to the lower frame.



Really the only thing I have to work on at this point is electronics, I finally took some time to disassembly my old control box. It was a bit of a shame to cannibalize all of that work, but it wouldn't fit in the simulator as is.

Here it was in all of its glory.




And now



A whole pile of parts leftover.



So what I am working on now is mounting everything inside the control box and finalizing wiring. A big part of that is the switch panel that sits on top of the simulator. Here Is the design so far.



I have my 3d printer printing non stop and I am working on final electrical schematics now, I hope to have things up and running soon.

Also, I am still working on the 3d model as I move along, have some updates that need to get done to that too.

Further progress on my switch box, I started to print parts out and then realized that I had a made an assumption on how the new mounting system would work. After already printing out the side sections I found this little error.


I made a correction to the design and I was able to make it work without scrapping all of my existing printed parts.


I started by disassembling the old control box and salvaging all the electronics.



I then cut the existing aluminum extrusions to fit the new design.



Assembly part 1 with the help of some extra brackets for alignment.



assembly part 2, Monitor installed and brackets removed. all connections are internal hidden fasteners.



I got the electrical box assembled onto the frame, the new design makes assembly much more complicated.




Here is the completed wiring of the switches.


And the completed panel.



Now I plan on revisiting the actual switch plates, I'm not happy with how the end result turned out. I have been experimenting with sanding and clear coating them but I need some more experimentation to find the right combination.


I also started to mock up the inside of the electronics enclosure.


That's all for now, but I expect to start wiring soon.

One last bit, I updated the cad model to be mostly parallel with the status of the actual rig.

Beautiful work, Hoddem! I really like putting the actuators on the base for less “unsprung” weight, too. Apologies for not reading through until now but might have a solution to the flex mount issue - kinematic mounts. We used to use these on cameras and other parts that needed freedom to move/tilt but precisely constrained in location.

A ball and cone locate one point in x, y, and z. A groove and ball just constrains in 2D, and the plane constrains in just one. The ball rotates in the cone, rolls in the groove, and rolls on the plane. But that arrangement lets the groove and plane take up contact point dimension changes as the platform moves.



Amazing work, though!

Hey Zed,
That sounds exactly like what I was thinking about doing before I came up with the TPU inserts. Ultimately I didn't feel comfortable with floating connections at this point. Well see how the TPU inserts workout and if needed I can explore other options later.

Thanks for the idea and the help with the Reverb G2.

Not a lot of detail here but some more pictures, I am slowly chipping away at the wiring.
couple of things I did.

On the left side of my rig, which will be the entry/exit side I have some AC Infinity fans and smart controller. I didn't want to spring for another set of those so I just picked up their plate and mounted my own 12v fans for the right side.





I made some 3d printed mounting brackets for my open frame pc and screwed that down.



I added a power input port to the front of the base. I will just grab an extension cord and plug it in when I want to use the rig vs having a permanent cord to manage when not in use.




I needed a place to mount all my relays, voltage level converter, power distribution etc so I used the top of my transducer amplifier.



I also spent a little time cleaning up the wiring on my argon servo drive for my OSW. all connections between the servo drive and the discover board are now internal.






And here it is about 25 percent wired, I actually have it about half done, but I forgot to snap a picture.



One last picture, I like to keep my garage organized and I finally went though all my extra sim gear from various project over the last several years. I ended up with quite the pile of stuff that unfortunately ended up going to the bin. It was bitter sweet, but it also felt pretty good to know that I'm not hoarding anything unnecessary. Side note, if anybody is looking for sabertooth 2x60 motor drivers with dc motors and encoders, I have some for real cheap.



More to come soon, I have been making a big push to get this thing running.

I have a couple of things I need to get done before I can finish the wiring, one was mounting the remaining 4 transducers. I currently have 4 transducers at the corners of the rig, but I have additional transducers for the pedals, shifter and 2 for the seat. I started with the easiest one, the shifter. It was as simple as just bolting it on. I have seen some people mount them on the shifter itself, but I think this will be ok for now.



Next up the two for the seat. I have had this plan in my head for as long as I can remember, but I was hesitant to drill into my seat until now. I picked up some brad hole nuts so that I could screw the transducer to the seat without any protrusion inside the seat.




First I stripped the inner liner off my seat, it was mostly held in by Velcro and came out pretty clean.



Then I Positioned the transducers, marked out and drilled the holes.


Here are both the bottom and back, temporarily mounted.



Here is the inside of the seat, the nuts protrude about 1/16" and after the seat padding is on they are undetectable.


And the seat back where it belongs.


I was really hoping this would be the last time I would have to pull the seat off, but I ran into a snag. The crossbar for the sub strap was hitting the spring terminals for the bottom transducer. Old picture from way back.



Not a huge deal, I just rotated the transducer 90 degrees to eliminate the issue. I also took this opportunity to run the wiring for the seat.



Last is the pedal transducer, poor planning on my part in that I forgot the cross member to mount the transducer on. I will have to disassemble the pedal rack and put in the cross member, more cutting and drilling.



Finally, I have tested everything except the fans and transducers at this point. I just started wiring the transducers and wire for the fans is on order. Once I verify everything functions I will startcable management on the rig and eventually set it on top of the base.

Your build is very inspiring, great work!

Pedal tray reworked to add the crossbar, transducer mounted and wiring sorted


While I was working on the pedals I finally took care of a nagging issue. The heel plate on the CS v3 pedals is floating and while I'm driving the plate is constantly flexing and hitting the bracket for the electronics box. its not a huge deal, but the tapping kind of drives me nuts.

here you can see the electronics bracket. I'm not sure if the bend is slightly off and that is why the heel plate is hitting it, but the floating heel plate has too much flex either way.



Hard to see, but the heel plate is just slightly above the electronics bracket, any weight and heel plate flexes down and hits this bracket. It's a poor design in my opinion.


My solution is to make an insert that removes the flex from the heel plate.

3D printed parts of course.





And with the heel plate installed



There is still a very slight gap between the bracket and the heel plate, but now I have no flex at all so the annoying clunk sound is gone.

I appreciate that, It's been a lot of fun building this thing and hopefully soon I will be using it.

Two steps forward, One step back.

I got up early today to get some quality garage time in before the family woke up and I finished running the wires for all 8 transducers. I was running through some initial testing and noticed some popping noises coming from inside the amplifier. It took all of 5 seconds to realize what was happening and I pulled the main power, but it was too late and the damage was done.

I pulled the top cover off the amp to do some investigating.


It didn't take long to find the issue



In the picture above the horizontal resistor is 150 ohm 1w and the vertical one is 10 ohm 1w. It looks like the 150 ohm resistor died causing a short which then caused the 10 ohm resistor to overheat. The 10 ohm resistor is still reading ok on a multi-meter, but its clearly damaged from heat so it needs to be replace.

I actually tried to replace these without removing the amplifier, but It was clear that I would probably cause more damage if I didn't pull pcb out of the amp.

Here are the two damaged resistors after removal.



and the PCB ready for the new ones. Lots of heat damage on the surface.



I don't have any 1W resistors on hand and I don't want to mess with making one out of multiple smaller wattage resistors so I ordered what I need and I should have parts in a couple of days.

I looked over the rest of the amplifier and as far as I can tell there is no visible damage anywhere else, I also tested a bunch of components related to that channel and all of them looked good according to my meter. Hopefully the resistors are enough to fix it, if not I will keep investigating as needed. If I can't fix it I will have to decide whether to buy another one of these amps or go a different route.

I will have to park the rig for a couple of days while I sort this out. Kind of a bummer because the last thing I wanted to do was test the fans and then start final wiring.

Unfortunately the new resistors did not fix the problems with my amp, in fact the new 150 ohm resistor lit up like a Christmas tree as soon as I powered on the amp. I knew that some serious diagnostics were going to be needed so I ended up pulling the PCB out of the amp and going through almost every component one by one.



It looks like at a minimum the power transistors are fried along with a few smaller transistors and the 5W resistor. Basically all of the high power section of the amp board is toast and it was back feeding into the low power section which did some more damage. I have two channels (5 & 6 on this board that don't work, one of them is expected as I found and removed the damaged components (5), but the other (6) I cannot find any reason it doesn't work. I think I will have to start doing some powder diagnostics and maybe even pull out an oscilloscope to see where the issue is on the second bad channel.

So at this point I have a decision to make and as I see it I have 3 options.

1. Buy the parts to attempt to fix this amp, I can get a new amplifier board for around $30 and then transfer components as needed to this one. worst case I end up no furhter ahead but i'm out the money invested.
https://www.ebay.com/itm/265280515556

2. Buy another PT8000CH amp for $250, guaranteed fix and I would have spare parts for the future even though I hate the idea of storing another amp just for parts. Also, these amps are not the greatest quality so buying a second is not something I would be excited about.

3. Convert to a different amplifier setup, maybe some 100W per channel Class D amps with power suppliers ($200). I could even gut the existing amp and place all of the new components inside.

I'm going to hold off on deciding until I get to look into channel 6 not working, If I can get that working again I will probably just buy the $30 amp board and try to salvage this amp.


On a positive note, I was able to test out the fans finally and everything works as expected. I'm using a sabertooth 2x32 to drive 4 seaflow fans as wind generators. The sabertooth has 2 channels so I have my upper fans on channel 1 and my lower fans on channel 2. This will give me some control over how they work, I can set all 4 fans to change with the speed of the car in iracing (simdash) or I will probably setup the lower fans to always be on at a set speed for continuous driver cooling and the upper fans speed controlled. I needed a way to mount the lower fans so that they point at the correct location so I came up with a 3d printed bracket. In my opinion, the bracket looks ridiculous so I may attempt to fab something out of aluminum in the future.




All of this amp nonsense has really slowed me down, but I will at-least get to start cable management of the upper portion of the rig now.

I got to spend a little more time working on the amplifier, I even got to break out the Oscilloscope which is always fun.



I started working my way from the input signal through the amp to see where I am losing the signal at and it appears to be fine right up to the pre-amp pcb.

Here is a comparison of a known good channel vs the bad channel. The signal is getting flattened when it goes through the pre-amp. I can't for the life of me figure out why though, I have checked and re-checked every component and I cannot find the issue.




The vertical PCB is the board in question, it has 3x 2240 and 3x 970 transistors but they all checkout during testing. I'm sure I am missing something so I will keep working on it. It really helps to have a good channel as a reference though.


The way these boards are designed is both awesome and horrible at the same time, all of the traces are on the bottom so it is fairly easy to map out the circuit. On the other hand all of the components are on the top so I have to flip back and forth to determine what component I am working with. I ended up taking a couple of good pictures and working from them vs flipping the board over all the time.




In any case I have ordered the amplifier board off ebay and will harvest the required components from it to try to rebuild this channel.