New Update on the "Never Ending Simpit Build"!

Conundrum: I wanted trims for my elevator, rudder and Ailerons but whenever I tried to make some they were way to "touchy". A very little movement of my levers resulted in huge movement in trims. Soooo, I built something that would allow alot of movement in the levers a very little on the pots.



The pit is a bit torn apart right now as I have been experimenting with options for my control layout. You can see that I moved the throttle assembly back about five inches, leaving a gaping hole. I will think of something to cover it up. The two levers (large knobs) on the left side are the rudder and elevator trims, the aileron trim is on the right.


There were several issues that I had to work out;

1. how to get one turn of the knob to equal about a mm of travel on the pots,

2. The system that I worked out works but turning too hard on the knob would result in breaking my new gear assembly so I made the gear assembly free standing, or not attatched to anything other than the knob. This allowed the assembly to be rotated if it reaches the end of its travel.

3. how to attatch the knob to the assembly and yet make the entire assembly to be ridgely affixed to the simpit.

The final assembly looks like this:





A run on the CNC gave me those black (actually a recycled plastic material)bearing housings which bolt to the inner panel of the simpit (either inside or outside as you notice from the first picture). More of the recycled plastic connected the 2-56 threaded rod on the assembly to the 1/4 bolt for the knob, both ends being tapped for the proper thread size. For now I put a bit of hard foam behind the knobs to create a stiff resistence to movement which will keep them from turning accidently.

The assembly itself is made of two gears, one standard and the other a worm gear. The CNC was again used to make the assembly plates (I ran it a bit fast resulting in the plastic melting to the bit and "buffing" the edges of the cut..which is where that white blemishing comes from...the cut was otherwise perfect.

A few closeups of the assemblies:








The system works to perfection. I took up a brewster Buffalow and an ME109G both trimed out to level hands off flight with a cuple of turns each on the trims.

My Simpit is starting to look a bit like Frankensteins monster but when I get everything working and in place for comfort of movement I will build Simpit MKII from what I learned on this one.

David

Thats awesome love the home engineering aspect, I have to do that on my projects too!

That looks great! I spy some yellow ny-rod in there too.

g.

HHF, thanks.

Gene, I had toyed with the idea of making the assemblies remote from the levers. Long nyrod (Sullivan Gold-N-Rod) would work perfectly. Unfortunatly I would still have had the issue of turning the worm gear too far and screwing it up (pun intended). Having the assemblies attachted to the knobs allowed them to move freely (twist with the knob) if it is turned past the end point.

When I built the trim & flap wheels for the 109, I put bolts into the gear faces that would hit a stop and prevent the gear from being over-rotated.

g.

I thought of that, but the gears are pretty light weight and the torque from the large handle/knob would easily overwealm any stops I put on the gear and or pot. This was teh compromise between precision (keeping the assembly/connecting rod/handle in sync) and safety (not breaking anything). Overall it works very very well. It takes a full turn of the trim handle/knob to have any noticable affect on the plane....almost exactly what I was shooting for.

New updates:

I redid the instrument panel to have all the buttons my little heart desires:

The toggles have LED's so I can tell when they are in the up position.

The bodnar boards mounted under the 'hood'







I redid the 'hood' to better reflect the early engine access panels:



the CNC machine made me some great backlit panels. I also used the CNC to make the framework that the panels are mounted into (see the pictures above).

Amazing, If I ever tried to build one of those my girl would have kittens! And she just had to human babies so that's saying something!!!! Great Job, can't wait to see more!

That is just a pit packed full of Epic Awesome! VERY nice job!

I would strongly suggest you invest in some wire management classes however.

(Go buy yourself a roll of waxed lacing cord, you'll thank me later)



g.

OH I KNEW you were going to jump in on that one! lol

Beleive me, that is way more organized than it was the first time. Believe it or not most of the wires that you see jumbled up are not part of the controller setup. Looking close you can see the controller (buttons, etc) are nicely bundled and organized. Some of the wires are to the controllers but they are axis wires that I need to properly bundle (I have black cable sleeve on order from Xoxide.com). The majority of the wires that you see are mostly from my frankenstiened PSU setup. I took a Dell 750watt PSU and cut off all of the propietary cabling (the plugs) and replaced them with standard plugs but never got around to organizing them properly...one of these days I will.

Edit: I looked up lacing cord and found this very interesting website, thanks for the tip Gene.
http://www.dairiki.org/hammond/cable-lacing-howto/