Makers Point Trim Wheel Pro: The Ultimate Flight Sim Trim Wheel for DIY Enthusiasts
A 3D printed, analogue elevator trim wheel using a hall-effect sensor
Resources: [firmware] [model files] [assembly instructions]
What is the Makers Point Trim Wheel Pro?
The Makers Point Trim Wheel Pro is the ultimate flight sim trim wheel designed specifically for DIY enthusiasts who want to enhance their flight sim experience. This 3D printed unit is fully compatible with Microsoft Flight Simulator 2020/24, X-Plane, Prepar3D, and FSX, making it an ideal addition to any PC setup. With a single clamp, the unit can be easily mounted on (or under) your desktop, and the Trim Wheel Pro lets you fly your airplane with enhanced precision. The elevator trim control utilizes a hall-effect analog sensor that yields an improved tactile feel and finer control as the wheel is moved.
This video shows TWP in action, which gives you an idea of its function and smoothness:
Improving Control with the Trim Wheel
Dubbed “poor man’s autopilot” the trim can be set to keep the airplane flying at a chosen pitch attitude! It can relieve pilots’ pressure on their yoke/joystick to maintain level flight. So improving control with the trim wheel is essential for any pilot (real or virtual) looking to enhance their flying experience, and a good controller makes this job a pleasure.
How does the Trim Wheel Pro enhance flight simulation?
The Trim Wheel Pro enhances flight simulation by providing pilots with a full-size wheel that allows for precise adjustments as you fly, allowing level flight to be achieved effortlessly. This hardware is designed for easy installation via USB; simply plug it in and start flying without the need for complex plugins.
This essential accessory equips your home simulator setup with a refined analog sensor that enhances your flying experience. With a simple download of the free SimTrim software, you can eliminate the ‘snapping’ problem, ensuring that this kit is not just an accessory but an integral part of your flight simulation toolkit.
TWP Requirements and Design Choices
So, why make this… As a keen flight simmer myself, I felt many of the commercial “off-the-shelf” trim wheels were a bit disappointing (especially the digital ones), and I thought I could do better.
When designing this, I had a few high level requirements in mind…
- The wheel itself had to be large enough to be manipulated easily.
- Should be accurate and precise.
- Should have a full 360o of rotation.
- The wheel had to turn very smoothly.
- Had to be easily mounted to a desk in multiple ways.
- Needed an easy way to adjust the tension without having to remove the cover.
- The Arduino Pro Micro used for this project has no screw holes, so we needed a way to mount it securely without glue.
- Should be easy to assemble.
- Should not require soldering.
I think the design achieves these requirements well, except for the need for soldering. Here’s more detail on this.
The physical wheel has zero play in it and is roughly 100mm (~4″) in diameter, so I think this is a good size. Not so small that it’s difficult to get hold of, but not too big, so it uses too much filament when 3D-printing. The wheel shaft sits in a groove that is greased well (lithium grease, so as not to eat the plastic over time), so this turns very smoothly, too.
With a 360o rotation hall-effect angle sensor at its heart, this trim wheel produces an accurate, precise analog signal with which to work. The hall-effect sensor is relatively more expensive than the incremental rotary encoders found in most trim wheels. Still, it is well worth it for its accuracy and precision.
There is a tensioning device on the unit where the tension can be increased or decreased via a single screw. This can be accessed from the lid cutout, so you don’t need to remove the lid when you want to make adjustments. A similar cutout at the front middle allows you to use a single clamp to securely mount the unit to the desk (top or bottom) or use double-sided tape on the base if you want to forego the clamp.
A compartment with sliding mechanisms has been incorporated into the unit, enabling the Pro Micro to fit securely. After the lid is fastened, the board is held firmly in position without screws or glue.
Lastly, each screw hole has a matching “nut pocket” designed for you to post the nut accompanying the matching screw. This makes it very easy to fasten and unfasten multiple times and avoids the hard work of creating your thread in the plastic.
Flight Simulator Trim Wheel Flavours: Analog Rotary Sensors vs. Digital Rotary Encoders
There are several differences between analog and digital trim wheels, but they can be summed up in one word. State. i.e., a digital wheel has none, whereas an analog does have a state. The sensor used in this design is an analog hall-effect one, but there are pros and cons to each, which are shown in the following tables:
Digital Rotary Encoders
| Pros | Cons |
|---|---|
| Do not need to remember their state because the trim position is just increased or decreased from the previous position, depending on which way the wheel is rotated. | Can get used to it, but overall, it is not a very realistic feeling. |
| Mimics button presses. Depending on the resolution of each button press, this can be an exact way of controlling your trim. | Specifically in msfs2020, many digital trim wheels count a button press as a very tiny change in pitch angle, meaning you will have to rotate the wheel a lot to get it how you want it. |
| No limit to how much these can be rotated. | There is usually a limit to how fast you can spin the wheel. Rotate too fast, and your changes won’t even register. You will need to slow down. So, it might take a while to get the trim where you want it. |
| Often implemented using rotary encoders, which are relatively cheap and small components, they are great for DIYers and big-name manufacturers. | There is not a good mapping between your physical wheel and the virtual one in your cockpit. i.e., turn the wheel a lot, and the virtual wheel barely moves. |
Analog (hall-effect p3022)
| Pros | Cons |
|---|---|
| Highly accurate and precise. | Snapping effect. As control moves from the aircraft trim control to the sensor, a snapping or jolt can be observed. |
| Expected proportional output. i.e., turn the sensor slightly, and your aircraft trim moves slightly; turn it a lot, and the trim moves a lot; all moves as expected. | Prices vary but are often relatively expensive. |
| Relatively small in size. | |
| It is a non-contact device, so it has a long life. | |
| Will always report their current position (state) no matter how quickly you turn it. Cannot be turned ‘too quickly’. | |
| It has 360o of rotation, so there is no upper or lower physical limit on the device. |
I have designed several trim wheels in the past, mainly using cheap digital rotary encoders. They all worked, but only this iteration with the hall-effect sensor was so good I had to share. If you build one, I think you will agree it’s excellent.
Printing and Assembling Makers Point Trim Wheel Pro
If you own a 3D printer, you can print the design yourself. The model files and firmware can be found on the resources page, and assembly instructions (including a parts list) can be found here.
Once you have printed all the components, carefully follow the assembly steps provided. Organizing your parts and tools beforehand is a good idea to streamline the process. Pay close attention to any specific instructions related to the orientation of parts and the type of grease or fasteners recommended, as these can significantly impact the final product’s durability and functionality.
After assembly, you will need to install the firmware on your device. The assembly guide includes instructions for flashing the firmware, so be sure to follow them closely. This step is crucial for ensuring that your device operates correctly.
Once everything is assembled and configured, perform a test run to check for any issues. The device should appear in your OS as another joystick controller type device, and the axis should move when the wheel is rotated. If you encounter any problems, consult the instructions again to ensure you haven’t missed something, or reach out to the community for support.
Finally, remember to share your completed project with others! Post your creations on Printables or Thingiverse. I would love to see your finished work. Happy printing!
Setting Up the Trim Wheel for Optimal Performance
TWP has been designed to be mounted to a desk using a single clamp, either on the top or bottom. However, you could also use double-sided tape to mount it to a desk, removing the need for a clamp.
Adjusting Tension and Sensitivity for a Personalized Experience
If you feel the tension on the wheel is not quite right, you can make precise adjustments to it using a single screw, which can be accessed at the rear of the unit. The convenient cutout on the back of the lid allows you to use a screwdriver to get to this screw. Turn and tension the wheel exactly as you prefer.
Sensitivity is defined here as the amount you need to turn the physical wheel to affect the trim tab in Sim. There are two ways to make these adjustments… Using the SimTrim software, you can move the sensitivity slider. The higher the value, the more sensitive the wheel will be.
You can also edit the MAX_TURNS constant in the firmware to a higher or lower value before uploading. This should be the only value you need to change (if change is needed at all) to adjust sensitivity within the firmware. It’s probably easier to use SimTrim to adjust sensitivity though. Changing the firmware risks damaging the unit.
Using SimTrim Software to Enhance the Trim Wheel Functionality
Many people may be put off by the word analog because of the problems synchronizing the analog axis’ with the sim. This problem is eliminated with the SimTrim software, so you will get all the benefits of analog and none of the downsides.
Compatibility with Major Flight Simulators
The wheel is compatible with any flight simulator, msfs2020/24, fsx, p3d, x-plane, etc. Just upload the provided firmware, and the wheel will act like any of the other joystick peripheral you have attached to your machine. The flight simulator will recognize it as a joystick internally, and you can assign the axis to whatever you want—presumably the elevator trim axis.
Is the Trim Wheel Pro worth the investment?
When considering whether the Trim Wheel Pro is worth the investment, evaluating its features and compatibility is essential. This fully compatible device enhances your flight simulation experience by providing precise and realistic elevator control. The full size trim wheel allows you to adjust the sensitivity of your inputs through the SimTrim software, offering a higher level of control as you fly. The Trim Wheel Pro works perfectly with various simulators without plugins, including msfs2020/24, fsx, x-plane, and prepar3d.
This is an inexpensive option compared to other on-the-market brands. However, a 3D printer will be required to print the parts. The model files for this are provided for free, as well as the assembly guide. You will have to purchase a small number of mechanical parts, and you will need to invest a small amount of time in assembly.
However, I think it’s a winner, and the benefits outweigh the small investment needed for flight simmers.
