Hi everybody,

I’ve just discovered I have a problem with my Fulcrum Yoke . I would welcome advice as to whether firstly my diagnosis of the problem is correct, or whether it is more serious and secondly whether my proposed method of remedy is sensible and sound.

Firstly the yoke model. Looking at Sergey’s photos my yoke is the updated one with digital sensors.

The problem - I first noticed on returning to MSFS after a few weeks’ absence is  that the A2A Comanche seemed to be requiring a lot of yoke pull back and excessive upward trimming during landing in order to minimise descent. Then by accident I discovered that if I pushed the yoke forward it would in, say the final quarter of forward travel, provide an up, not down input. I confirmed this on the controller settings of MSFS and on the Windows calibration tool. The “+” quite literally goes to the top of the calibration window and then reappears at the bottom and moves upward until the maximum inward yoke travel is reached. Real numbers on the calibration scheme confirm this. Pulling the yoke back to its maximum gives a maximum reading just below where it rises to when the pushed in yoke reaches its stop limit. It is as though the whole control output has shifted.

I’ve removed the top cover and nothing seems untoward inside. At present I’m reluctant to disassemble any further unless it proves absolutely necessary.

My Diagnosis - I think that the problem may be related to one I had late last year when I found that the screws securing the main central guide rail to the bottom of the case had slightly slackened and the rail was moving on its longitudinal axis when I turned the yoke left or right. I’m thinking that during the period this was happening the wheel “slipped” on the toothed belt and calibration was lost. From looking at the sensor data sheet I see it’s got 360 degrees of travel but when it’s done one rotation does it start again which it must if my thinking is right?

If I’m right in my thinking is it just a case of recalibrating the wheel by marking the current positions and then lowering the belt and rotating the wheel to essentially shift the values “to the right” as it were?

If I’m completely missing the mark here can anybody suggest what is going on and what the remedy might be please.

Many  Thanks

 

David

11 hours ago, davidb47 said:

If I’m right in my thinking is it just a case of recalibrating the wheel by marking the current positions and then lowering the belt and rotating the wheel to essentially shift the values “to the right” as it were?

Hi David,

Spot on! We had a discussion with Chris on this matter when he changed the original design (with a plastic rack rail) to a belt. He has chosen the biggest practical wheel/ belt profile to ensure the reliable contact, but if the carriage rail gets loose (not being secured properly during the assembly) then the wheel might slip against the belt with the symptoms you've described.

To fix it just keep the yoke at the "mechanical zero" position and rotate the wheel against the belt until you get a pitch output in the center.

BR,

Sergey

Edited February 5, 20242 yr by SergeyPe

Thanks for your advice Sergey.  I did as you suggested and recalibrated the sensor with the mechanical zero. I was surprised by the amount of slippage, about 45 degrees. Went for a flight but had to set the neutral to 35% in The MSFS control options to regain centre. Cured that by restting the MSFS settings and restoring defaults in the windows calibration tool. Seems to work very well now with mechanical and electronic centres matched. Hopefully sorted and will see how it goes over next few days.

Again many thanks for your prompt help and advice, I really appreciated it.

Regards

David

You are welcome David; if you need any additional support, please don't hesitate to ask.

BR

Sergey