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Column Crossover and Deck Tutorial by Project45

(Original thread started on 01-16-09 by Ron Rollo)

I have been working on the columns and the floor components. Like the shell, my goal is to create a flight deck environment that mimics the real thing as close as possible. This is difficult to say the least since I have never set foot inside a real Lear45. Because Lear columns and yokes are not readily available, most, if not all of us will be forced to build something on our own.

 

I have put a lot of thought into this not just for myself but because my hopes are that others who already have a shell or those that are planning on getting one will use my ideas. This is not going to be like most flight decks currently out there. There are three different levels to the deck (floor), not including the sub floor or base platform. The columns will actually be ran across the top of the sub floor of my base platform. The system is actually very simple once you see where I am going with this. I have included five pictures to help illustrate the build project to this point. Updates will follow until it is complete

 

UPDATED 03-18-21: Column spacing from center to center is exactly 28.86" per Lear45 spec sheet!

 

The columns are made with a combination of two inch and three inch PVC with shielded 20mm I.D. X 47mm O.D. X 14mm wide bearings for about $4.00 each. I used two bearings setting next to each other at each end of the column assembly with a 20mm bolt running through them. I made two custom “A” arms out of white Polly board which attaches to the sub floor. The inside diameter of the PVC is 48mm, so I had to use some hobby plastic as a bearing sleeve to create that perfect fit.

 

There is not going to be a whole lot going on under the sub floor other than some springs to help hold things up right. I am planning to use braided Nylon rope which will be ran internally through the cross over assembly with the use of screen door bearings. I am also using two screen door light duty dampeners in the center of the assembly. The cool thing about this custom design is that when one dampener is working, the other one is resting. I made two Polly parts with the dampeners running between them for maximum strength, which reminds me….. For being a PVC design, it is super strong with less than 1% flex. Eric will be making the short trip down in a few weeks to check it out for himself and report back to everyone!

 

During the course of mapping and planning out the flight deck, it was determined that the floor needed to be raised up 1.5 inches into the shell, or in other words, 1.5 inches above the sub floor. You will notice in one of the pictures that I used three sections of half inch plywood to build up the floor under the seats. I also added 1.5 inches to the bottom of the TQ assembly which in turn also raises the MIP and glare shield up into the shell. The fit of the 54 inch MIP and the shell is incredible. I will have some pictures in the near future. In the meantime, enjoy these pictures:

Ron 169

 

Ron 170

 

Ron 171

 

Ron 172

 

Here is the picture I promised, although a little early, of what the rest of the floor will look like meshed with the TQ, Center Console and the column system. Imagine it with carpet and heel plates on it! I copied the exact design of the column cut outs in the floor so that the column boots will fit and look like the real thing. The carpet will actually run up the out board sides of the fuselage walls a few inches.

 

I will be taking a break from the columns and floors and moving on to creating panels with Scott and Vince with the CNC machines. There may be others that join in on the fun and development as we move forward. Remember, this or our hobby so have fun with your project:

Ron 173

 

Update and announcement of the deck being complete in L45-002!

Over the past several days, I finished the flight deck "DECK" and wanted to share a few pictures to help tell the story. The deck in my L45 shell is a three level system. The first level is what I call the "raised floor" which is under the seats. This section is raised up above the base platform by 1.5" and it's purpose is to effectively help mesh all components of the flight deck together. If this "raised floor" section was not built, then I would have been working outside of, or in other words, below the frame of the shell.

 

The second section is the "ramped" area where the control columns are found. As it turns out, 98% of the control columns fall under the ramped deck and above the base platform. This means that I don't have to dig under the base platform for maintenance!

 

The last section is the raised pedal platforms. They are about 6.4" above the base platform. Again, there is plenty of room for the dual linked control pedals above the base platform. I may find myself building the pedals sooner than later by the way.

 

I went a few steps further in the design of the raised floor under the seats. I cut out 10" X 16" holes under the two pilots seats to accommodate base speakers in the future. I also cut out an area under the "Butt Kicker" unit to create a pocket for the bolts, AND to hopefully add to the sensation of the low frequency vibrations that it will be sending off.  See photos:

Ron 174

 

Ron 175

 

Ron 176

 

Over the past few days, I learned a few hard lessons that I will share with you. First off, make sure that you leave enough carpet to go up the sides of the fuselage, especially on the ramped portion of the deck. I looked through several photos and found that the carpet travels well up the side walls in this area:

Ron 177

 

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The other lesson is to use 1/16th inch thick aluminum for the heel plates. I first used .025" thick aluminum which looks good, but it will not stand up to the constant beating from the heels of the pilots! If you are wondering what the dimensions are, I cut mine to 3.75" X 18", pictured below:

Ron 180

 

Ron 181

 

Ron 182

 

I built everything to be module so that things can be pulled out with ease. There are six bolts holding the rear raised floor to the base platform. This will also help transfer vibrations to the rest of the simulator.

 

I hope this information helps those who are looking to take their projects to the ultimate levels in flight simulation! If you have questions please ask.

 

UPDATE: Hey guys, especially you with Project45 shells!  This week I have been working on the pedal assembly and I had to modify my raised floor section. Some time ago, Scott took that field trip into a real Lear45 and confirmed, proved or disproved tons of things. One of them is the fact that the pedal assemblies ARE directly behind the columns. Early on, I was under the impression that they were off set a tad in board.

 

Long story short, I went ahead and mounted my rudder pedal assemblies directly behind the columns, but this meant I had to add 7/8th of an inch of material to the raised floor where the assemblies come through. This was necessary so that the rudder pedal covers would cover the opening properly:

Ron 183

 

Here the modification is completed and 7/8th inch of material and carpet have been added. Compare to photos earlier in this post:

Ron 184

 

In this photo, you can clearly see the additional material from the back side. Wood glue and clamps does the trick:

Ron 185

 

Here you can see that the rudder pedal covers fit over the opening properly. No need to show you a before picture right? Notice the the covers are now lined up directly behind the column cut outs.

 

Speaking of things being lined up, you will probably notice that the heel plates are off set and not lined up evenly. This is how they are in the real aircraft for some reason.

(Posted by Ron Rollo on 10-10-10)

MAJOR UPDATE!

It has been on my list of things to do and this past week I have found the time to get it done! The job started off as swapping out the PVC cross over with a steel tube to give it more strength. I ended up not doing this because I do not see the issue that others were having. I used "U" clamps and a shim under the center of the cross over tube to solve this issue. I do not have any play what so ever in my column system.

 

However, Shane and I have been going back and forth with our control column systems. He was having an issue with his that got me looking closer at my own. I did not like the feeling of an indent at the top center of the control column movement. Some would say that it's a good thing to have but it is not in the real L45 and I don't think it should be here either.

 

So after much thought and searching on the web, I found what's known as your basic Suzuki GSXR 600 750 Steering Damper. It's off a 2007 crotch rocket:

Ron 186

 

Another problem with my older design is that if you pulled the columns back into your lap and let them go, they would bounce back and forth wildly. (Not that you would ever let go of the columns in flight.)

 

This steering dampener is just the right size and strength for what we are trying to accomplish. By the way, I do believe any motorcycle steering dampener will work. You can find them used on eBay for about $20.

 

Oh yeah, I thought mine was broken at first but then realized that it had a little air in it. I removed the fill screw and added five drops of power steering fluid to it. It's not that it needed five drops of fluid as much as it needed to have the five drops of air removed:

Ron 187

 

Here it is in place. I have about one inch of travel in each direction. Now when I pull the columns back and let them go, the columns return to top center under control without the bouncing back and forth.

 

The other big change in my design is that I replaced my screen door shocks with medium strength springs. Each direction has two springs. Each spring holds tension while it is is neutral, pushing forward or being pulled back. This eliminates the notch or indent feeling that was there with the old system:

Ron 188

 

I used shrink wrap at the ends of the springs and 3/4" diameter pieces in the middle to "Shut Up" the springs. They were not really noisy as I was testing them, but if I hit the base really hard, you could hear them. Which means after the sound system is working, they could get noisy. But as it is now, it's a non issue:

Ron 189

 

For those guys who have a lower column kit from me, you can still use them with this new design. The only thing that will not get used is the fancy slide that I cut.

 

I completed the Pot towers for the YAW and the pitch axis today. They are made out of wood and aluminum "L" angle. I used two of Tom's Pot brackets at the top:

Ron 190

 

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The same rules apply to both of these Pots. You can clearly see the pivot point on the pitch. It takes a little time but the idea is to find the spot that gives you maximum travel but does not bind the travel rod or put tension on the Pot. In my case, I was able to capture 95% to 98% of the Pot:

Ron 192

 

Another thing that I got schooled on was the wiring. I was using a very small, maybe 24 or 26 gauge solid wire. It was actually alarm system wire. As a matter of fact, it is still wired up to the toe brakes in this picture. I found that 22 gauge stranded wire works best. 20 gauge will also work but you get much more wire on the spool with the 22 gauge:

Ron 193

 

In this picture, the TQ is in place. Notice the cross over that helps protect the linkages? I will end up putting at least one more in the lower end of the TQ. This is so that all the large and heavy cables will have something to rest on rather than pushing or being up against the mechanical linkage arms.

 

(Posted by Scott Wegner on 11-10-10)

Nice ideas. Are you still using springs underneath as well? Personally I didn't like springs because of the noise but seems you found a solution to that. I will say that I cant believe you don't notice the problem with the PVC crossover. I have mine set with the U-clamps as well and shimmed but that has nothing to do with the torsional issues we experienced. Do you have yokes attached yet? You may not notice much of an issue until you do. I would suggest attaching some weight representing your yokes to the top of the columns and make sure they are rigidly attached. Then just lightly shake the top of one column back and forth and you will feel the problem of the feedback from the other side.

 

Not trying to question you here but I also don't want you to get everything set with yokes on then realize you have this problem and have to tear it down and do it over.

 

(Posted by Ron Rollo on 11-10-10)

I do still have the springs mounted below. In total, I have four smaller spring below and the four larger springs that you see in the pictures above.

 

In the next few weeks I will be working on the roll axis and working with the yokes. Then I will know for sure that I have no issues, OR ISSUES! As it is now, the columns are super smooth. If it comes down to pulling it all apart and modifying something, then that's what I will do, it would not be the first time. But so far, I am still not seeing the need to go with the steel tube.

 

The cool thing is that if I get my yokes mounted and I notice what your describing, I know what I need to do to fix it! We will know soon.

 

(Posted by Ronald Prater on 12-31-10)

As usual, I can't find this specific steering dampener anywhere nearby the Netherlands, so I will get it from eBay/USA. It definitely looks like the perfect solution! Ron, can you give some details on the springs you used?

 

(Posted by Ron Rollo on 12-31-10)

I used medium strength springs to replace the screen door dampners. The exact size is .563" DIA X 8.5" long X .054", part# C-319, made by Century Spring. Here in the USA, we have a hardware store called "Ace", which is where I picked them up at. The exact spring that I am using is not that important or critical. You should be able to find something that will work.

 

While I am on this thread, let me say this. My pitch works perfectly as I have it set up right now. But I don't have any yokes or column heads on the columns yet. So I may have to either move the spot where the springs attach to the floor or add more springs to level things out or add more resistance. So keep this in mind while your working on your set up.

 

The forward and aft movement is still approximately 6" forward and 9" aft.

 

(Posted by Will Sasse on 09-10-14)

Thought I'd update this thread with a minor mod I've made to my raised floor:

Knowing I will have to move sometime soon, I need a way to dismantle the sim in as easier way possible. I am about to cable the control columns using Ron's methodology, but this would lock a lot of the floor system in place requiring disassembly of the control columns to move.

 

So, I came up with a small mod to the raised floor at the rudder pedals:

Wills 12

 

I made the mid cross-over removable by reinforcing with a piece of wood and holding in place with lots of screws. This makes this piece removable into the cockpit when the need arises, and allows the removal of the control columns as a single unit, no need to have to remove the cables:

Wills 13

 

I have also cut short the two narrow legs on the TQ where the control column passes through to make this easier to move.  Simple, I know, but hopefully effective.

 

NOTE:  All the pdf and dxf drawings are available here at the bottom of this thread!

 

(Posted by Ron Rollo on 01-26-15)

Over the past year or so I have been looking to find ways to tighten up the pitch and roll in the column system. Even with all the springs and hydraulic steering dampener I have installed, the feel was still too loose for a business jet, like say the Lear45. LOL Every time Greg Branch comes down to visit and fly he reminds me that the columns are still too loose.

 

So yesterday, I started looking for new ways to tighten up the pitch and roll. First off, let me remind you of what the spring system looked like a few years back:

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Notice that the springs appear to be very relaxed.

 

What I found was that I could turn the sub cross member 90 degrees to get some more spring tension on all four springs under the floor:

Ron 196

 

 

And, I moved all four springs out one hole to add even more tension:

Ron 197

 

The end result is that this is a significant improvement over the old design. But with that said, it is still not as tight as I would like it and I will be looking for more ways to stiffen the pitch in the coming weeks.

 

As for the roll axis, I added another zip tie to the top drum in each column head.  See the column head thread for more details HERE

 

The roll feels pretty good and all in all, the whole column system feels good. One day I would like to add a little force feed back to simulate wind or turbulence.

 

(Posted by Ron Rollo on 11-02-16)

In my sim, I would say that the springs under the floor do 75% of the work keeping things upright.  In a few weeks time, (I hope), I am going to start experimenting with the Pitch Trim Bias switch. I am going to use this switch to help fine tune the columns one way or the other. It will be a cool little addition.

 

I think I posted this idea in another thread. But the idea is to find a power seat worm gear motor like this:

Ron 198

 

Then I am going to take this worm gear and hook the springs in the right side of this photo below to the part that travels up and down the worm gear. The motor part of the worm gear will be mounted to the base of the shell:

Ron 199

 

Then it is just a matter of hooking in 12 volt power and the toggle switch.

 

Even though there will be approximately six inches of travel for the trolly on the worm gear, I only expect about 1.5 inches of deflection of the columns, and that is measured at the top of the columns. Reason being is that all the springs below are doing 75% of the work. This idea will not effect the pitch trim and will not interfere with the full motion of the columns. All it is basically going to do is slightly change/adjust the columns resting point. (Pitch Trim Bias)

 

Keep in mind that in the real plane it works a little differently!

Over the past three years, I have been planning to rebuild my sim.  Just recently we have finally got to the point where work can start to take place!  One of those planned updates is deep within the sim and that is the column crossover assembly.

I've been putting off the changes I wanted to make to this area because of how deep I needed to dig into the sim.  This photo shows just how much needed to be removed, almost everything!

My goal is to make the column crossover stronger, heavier, 100% to scale (28.86"), quieter, stiffer, easier to adjust and add the pitch trim bias function.  My plans for the Pitch Trim Bias linear actuator is not exactly how the real one works but based on the overall design of the Project45 sim, it will be a nice addition!

The next thing I want to point out is that some of the upgrades I am going to be doing are not all my ideas.  As an example, using steel tubing was originally Scott Wegner's ideas.  Using dual steering dampeners was Maciej's idea.  The actual column spacing of 28.86" was discovered by DonnyRay.  So now that I am at a point in my new v2.0 build, the beginning, I am free to implement the best ideas and get rid of the bad ones!

Speaking of bad ideas, or as I like to say, "The best bad ideas we had at the time", here are a few photos of what I am replacing.

I used "U"joints and a plastic shim under the center point of the column crossover for extra support.  Remember, the column crossover is made of PVC (plastic) and it gives.  I found that "the give" was not terrible but wanted  reduce the effect as much as possible without rebuilding the whole thing several years ago.  The side effect to this early fix was additional friction and noise, but still, not a deal breaker for what it was worth back then.

Here is a photo of the old lower column crossover assembly.

And here is a photo of what I use to call the "Meat and potatoes".  This was my first original bad idea where I used screen door spring loaded openers!  The curved slots at the top created a good size dead zone or null in the center position.  The new pieces will be referred to as Pitch Control Arms.

The one thing that is not easily detectable is that in my early column design, I have the column distance set at 28.00" from center to center.  This was the best information we had at the time.  Thanks to DonnyRay for taking a field trip out to Bombardier in Wichita Kansas, he came back with more real world information, documentation and illustrations than you can shake a stick at.  That's the really good news.  The not so good news is we now know almost all key measurements including the column spacing which will cause some of us to address these areas.  Did I mention 28.86" yet?

I wanted to take a moment to point out some of the early wrong turns so that you will have a better appreciation of where we are heading with the new v2.0 design.  Last point before I move forward, the changes I am making, as always are designed for the guy with average fabrication skills, common shop tools and materials that can be found at your local hardware store.  (I consider myself to have average skills)

The first thing you will need to do is locate a 2.375" diameter steel tube.  Turns out Lowes (a hardware store found in the USA) sells fence post with exactly that diameter for only $23 plus tax:

Close up of the label:

If you are using my existing lower column crossover assembly, the exact measurement you will want to cut your steel tube is 26.1875".  Once you replace the PVC tube with the steel tube, your center column to center column measurement will be exactly 28.86".

One of the minor issue with increasing the column distance from 28.00" to 28.86" are the mounting and column holes in the base frame.  I made a jig for the column holes and made slightly longer end pivot point feet so that I could use the same mounting holes in the base frame.  This photo shows all the parts that are needed to make the retro fit.

Here is a closer look at my new Pitch Control Arm design.  The main column crossover hole is exactly fitted for the 2.375" tube.  Notice that there are several .25" holes along the top?  Those are adjustment points for the springs mounted to the floor.  (Actually, the forward set of springs will be mounted to the Pitch Trim Bias linear actuator.)  The adjustment holes are spaced out in 5 degree increments.  The center top hole is for a structural bolt.

 

Pulling the old column assembly apart, reusing most of the parts and putting the new steel tube and Pitch Control Arms in place is fairly self explanatory.  You will need a 8-32 steel hand tap and a super flat surface so you can insure the columns are even.  In this photo, I am insuring the two Pitch Control Arms are in the center, properly spaced and level.  Notice I have the column assembly upside down?

 

One other minor but very important update was to open up the wire harness holes at the bottom of the column joints.  This was not an issue prior using the FDS SYS boards, but now that we are moving 100% to our own Jet45 Arduino solution, we need to insure that we can pass a 10 pin connector though this hole.

And here is the freash new column assembly equipped with dual hydraulic dampeners!

If you remember in one of my earlier threads, I was trying several different things to hush up my springs.  One solution was to use shrink tube and a heat gun which worked very well.  The problem I found when I took everything apart was that the shrink tube was wearing in areas where the metals would have been rubbing.  So I am going to try Plasti Dip which is used to dip tool handles in and make plastic handles:

 

One of the more challenging parts of the retrofitting was cutting the larger column holes in the floor, if your goal is to make them look nice along with functional.  That is where the wooden jig comes into play.

You know the old saying, measure twice, cut once.  You really want to make sure you have all your measurements right here before you start cutting anything.  After finding the sweet spot, I penciled in the lines and used a drill to mark the four attachment holes.

I have had this drill for 20 years and it finally came in handy.  It has a leveling bubble at the top that insures you are drilling a straight hole, level to the Earth's core which is important!

Now you have jig mounting holes on the underside of your base frame to properly mount the jig!

All set for the fun part.  Route out the hole.  I used a vacuum to try to keep the dust down.  I am not sure how much this helped if any.

And now we have a couple of holes big enough to accept the 28.86" column assembly.  It should be noted that if you are just starting your build, your column holes in your base frame will be smaller and perfectly lined up with the columns.

And here we have the lower column assembly in place!  As you can see, the column holes I just opened up in the base floor are not lined up with the columns, but just big enough to make it work!

A close up look at the Pitch Control Arms, dual hydraulic dampeners, springs and the pot rod.  Most guys are into Hot Rods, where we are looking at pot rod photos!

At this point, I need to make a few very minor adjustments but the main thing I am waiting on is the delivery of the 4 inch linear actuator.  Once it arrives, I will complete the retro fitting and update this thread.  So far, everything is looking and feeling really good!

 

Good tip about the plasti dip!
I will go and see if i can find to buy it somewhere...

Really some nice work and detail in the photos.