SimTrim is a free software tool for synchronizing analog trim wheels.
What do I mean by synchronization? The sim maintains its elevator trim position, and your trim wheel has its own. Both can have very different positions, but only one can be in effect at any time.
Your physical trim axis/wheel state will always dominate the sim’s state as soon as you rotate it, even by a tiny amount. This leads to an instant change in the sim trim position, which often causes the aircraft to “snap” (suddenly alter its pitch) by a small or large amount, resulting in a difficult recovery.
So SimTrim synchronizes or aligns these two states so you never experience a sudden “snap”. It works with any axis on any joystick device and is easy to use. Just make sure you clear the axis assignments for the elevator trim axis within the flight sim controls (see: Enhance Your Flight Experience With SimTrim Today | Makers Point for instructions), and let SimTrim work its magic 
Many simmers will opt for a digital wheel because of these issues, which is a shame because an analog trim wheel is far superior to digital offerings. An analog device feels more realistic for adjusting pitch.
I have also made some 3D-printed trim wheels in the past (see Enhance Your Flight Sim With Trim Wheel Pro | Makers Point for my “flagship” version), but I realize that the problem cannot be solved through hardware alone, which is why SimTrim was born.
V1.0 – Key Points
- Brand new interface and framework design
- Detects and adds or removes controllers automatically and periodically
- Near real-time state updates of selected controller
- Automatic detection of when flight sim is running (displayed in the status bar)
- Option to sync an axis with flight sim via a simple switch
- Processes and sends synced axis data to a running flight sim instance via simconnect
- Can sync multiple axes with your aircraft’s elevator trim at the same time
- Option to adjust the trim sensitivity of your assigned axis on the fly via a simple slider
- Option to reverse the axis so that clockwise rotation becomes counterclockwise and vice versa
The following excellent video from SimHanger demonstrates SimTrim in action in Microsoft Flight Simulator, and shows just how useful the analogue and digital trim functions are:
Support
I have set up a Discord server so you can offer feedback, post bugs, suggest improvements, or just discuss things: https://makers-point.com/community/. I would be delighted to hear from you.
You can also use the following contact form if you wish to message me directly: https://makers-point.com/contact/.