I have added proper photos to the twin collective assembly manual, it looks really detailed now. You can also use it to build the single throttle lever, as they are very similar. I recommend looking at Peter’s single collective build log as well!
After flying with a spring-loaded reinforced gimbal for a while, I noticed that slight backlash has developed in a stick connector part. While it was absolutely tolerable and that part can be replaced easily, I thought it was a good idea to design a new cyclic frame for those of us who value absolute precision over being able to remove the stick when not in use by simply pulling it off its socket. The new stick frame is based on M8 bolts and mounted to the gimbal with nuts. The cool thing about it – you can easily adjust stick grip inclination (you can make a copy of AS350 stick for example) and fine-tune its dimensions to suit your anatomy. It can still be attached or detached quickly but requires 2 wrenches to tighten/loosen nuts properly. I think it will be a new recommended default for a spring-loaded cyclic.
As always, you can find parts for it on GitHub.
Here’s how it looks (note a slight inclination of the stick on the second photo):
I have installed the same clutch pedal springs from LADA 2101 to pedals and made a short test flight of the upgraded hardware in X-Plane.
WOW, THAT NEW FORCE TRIM MODE IS AWESOME, SO ARE THE SPRINGS (like that, boldly, in caps)! Springs have actually added precision and made flying really comfortable. This short flight in a 407 probably felt like the best flight in it ever.
It really changes everything. I’ve been able to remove hands from the controls and pour myself some coke while flying the helicopter with pedals only.
I will need a couple of weeks to test mechanical strength of things, and if nothing breaks, will definitely recommend everyone to try a setup with springs!
A short video of landing:
I have finally been able to go to the local car parts shop and buy some springs for the gimbal. Here’s how it looks now:
I should start by saying it works just great. These springs are from some Lada’s clutch (i think they’re for the pedal), they are 55mm long when compressed and about 11mm wide. I am pretty sure any similar spring will work great, just pick one with light or moderate tension.
More (a lot more) below!
It probably needs some editing but is quite detailed where I think it’s important and should be helpful when building a new gimbal.
I have added modified holders for the reinforced gimbal that Guido has asked for. Sadly I can’t test them myself, so please tell me how these mounts worked for ya mate =)
There are 2 versions: the “a” version has the same distance from magnet to the sensor as 6x6x4 one, and in the “b” version, a magnet socket is lifted a little for an extra tolerance (the magnet is 1mm wider so potentially can touch the sensor with its angle when turned, tell me if you encounter this issue).
I have printed the quadrant, its parts seem to fit together quite well. I have also added firmware for it, for now, it supports 3 axes (3 more can be added easily).
Each slider has a reverse mode, programmed as a separate axis, so we can fly STOL aircraft =) This is the first version of the software, more features will follow. Let me know if you have ideas of useful functions for it!
I really like flying helicopters, but sometimes I just want to take that Cessna 172 for a ride. Sometimes, I like flying TF-51 in DCS. Sometimes I fly STOL aircraft, and I know some of my friends love flying jets.
I have made a single prop GA control panel with three axes earlier, but that one only has 3 axes, and most of the times I am too lazy to go fetch it from the shelf and mount to the table. That’s why I decided to make something universal, that will fit the standard IKEA GUNDE chair frame, somewhere on top of the collective lever base. I want it to be connected and active simultaneously with other stuff at all times (I think we all can find a good use for some additional axes).
I also want it to be modular (stackable, from 1 to 6 axes, for now, tell me if you need more!), and I want full reverse support (there’s a problem with it usually). I don’t think it needs to resemble any particular aircraft, so it can stay universal =)
Here’s what I’ve come up with so far =)
It uses all of the standard potentiometer’s 300-degree travel range. Forty degrees of travel is reserved for reverse operation (various types of reverse will be supported in software), then there’s a small gap with a tactile detent, and the rest of its travel is used for main axes. I will start printing it soon and release it after I check that parts fit together properly.
I have found that an issue with the collective lever being a bit too stiff was not due to the counterweight position, but rather because of how upper cylinder hinge was assembled. I have improved this unit and achieved silky smooth travel regardless of a position of the counterweight. Thus, I decided to move it to where it can be barely seen, to improve the overall look of the lever:
I have finally managed to build the gimbal, and even tried flying with it on Aerobatics Online Caucasus sever in DCS =)
I can say it’s great! For now, I’ve used rubber bands for stick centering, and they work pretty well. I noticed that I haven’t been using the software force trim function much during this flight. A lot of heli pilots were online, so I’ve had a great opportunity to put both the gimbal and pneumatic mod for the collective to a good test 😀
I am waiting for 50mm MAL16-50 pneumatic cylinders to arrive, hopefully with them installed the stick will feel perfect. The collective pneumatic mod still holds together, I am beginning to think it’s really safe to use. A couple more weeks will show if I am wrong =) The new gimbal will be released tomorrow, if time permits, I will also be making a couple of videos about the new stuff soon.