Depth of floor void for linked yokes?

[Sean]

I'm close to starting to build my enclosure (737) and am creating a floor void in order that I may link the yokes at a later stage. I have a natural floor void of about 60mm and was hoping that would be enough space, as I was trying to avoid building the enclosure on a raised platform. But 60mm isn't that much.

I know the number of builders with linked yokes is few and far between, but does anybody have any thoughts on this? Could a link be made in a 60mm gap?

Thanks

Sean

[XOrionFE]

I think 60mm would be very tough.  You could build the way I did and put the crossover tube above the floor as a compromise and just put some covers over it to hide it.    I decided to go this route not only for space but for better maintenance capability.

[Trevor Hale]

Hey Sean,  If you could make it work with 60mm you would be a hero..  I think it would be a challenge with 140mm realistically I think you need a minimum 6" or 155mm in order to make it work..  But like Scott suggested, maybe something like he did will tickle your fancy.

Trev

[Sean]

Thanks for your thoughts. I was pretty much hoping someone might say "60mm is fine", but I had a feeling it would be tight. I was originally planning on raising the sim on either 6" or 8" floor joists, but then thought about using the gap under the existing floor. I was thinking it would be good not to have to step up into the cockpit, as you don't in the real thing (I think the floor slopes down ever so slightly as you enter a 737).

[Bob Reed]

I think 6 to 8" will get you what you are looking for. Every thing is so tight in the pit....

[ivar hestnes]

Hey Sean

I think a 60mm is tight too. I am sure it will be possible with some clever engineering. But a sturdy mechanism for linking the two columns together , will need some space I think. I use 200mm/8inches underneath my floor, and it is still a tight place.

Also have in mind that you might need maintenance on the setup in the future. Easy access without tearing apart the entire sim is something to think about I struggle with that, lol.

[Pegger]

having never built a linked yoke system, perhaps I am not the most experianced to answer the question, but I was just the other night looking up the specs on mounted bearings for my own applications, and I pondered the 60 mm height question based on what I had turned up in my research.

I believe the smallest mounted bearing hight you will be able to think about using is around 2 1/2" . This type of bearing would allow a shaft of about 1/2" in diameter to link the yokes for the push/pull action. so realistically, it's probably too tight. Again, I have never built one, and I am not doing a 737 so I don't really know what the mechanism would look like, but thought I'd add some info based on the parts I remember seeing the other day.

I suppose if you could find small enough mounted  bearings, you could make the link with a rod running horizontally under the rotation axis of the yokes, but then there is the question of how do you link the sprokets and chains for roll? If you could get small enough bearings, and small enough sprockets, you could make the motion work, and translate it all to under your center consol, where all the motions would get translated to the I/O devices. Looks liek there might be room for it under there from seeing you build pictures. Good luck with trying to save space. I know that's a constraint that I have to deal with as well.

Mike

Oops. I haven't seen pics of your build, but I am imagining the space under teh center consol in a 737 as having adequate space for some mechanical parts to read the motions.

[Aerosim Solutions]

You could do it quite easily with 60mm - If you have your pivot point say 80mm above floor level this would give you a lever arm of 140mm. You would have to have a elongated holes in the floor for clearance. Attach two small bars to to the bottom of each column facing backwards to other link arms which rise vertically parallel with the columns connected to a torque tube that can be mounted under the seats or under the floor. This is how I did mine and it works great and there is no free play in the set up. One piece column set ups either have too much flex or contain enough heavy engineering hardware to build a small steam loco! Many builders lose sight of the fact that the intention is to drive a tiny potentiometer and have each yoke column move in unison. It is not difficult!



Cheers Gwyn

Regards Gwyn

[Pegger]

That is some nice tidy linkage work Gwyn. Really nice to see too that my vision of the linkage is not far off what you have actually built. My vision for the tiny clearance is very similar to yours, where the horizontal rod with the green mounted bearings would be welded directly to the bottom of the yoke stand, and a set of mounted bearings would then fix the rod directly to the underside of the floor. Then the link arm whould be in the center of the rod pointing up into the cavity under the center consol, where the movements can be dealt with. To get the required strength to hold teh rod fixed, i would suggest flat head bolts through the top of the floor holding the mounted bearings. Perhaps a set of 4 bearings for good strength along the rod?

Maybe my idea has flaws that I don't recognize, but combinations of many ideas and adaptation of ideas that work, like Gwyns,may lead to a solution for the tiny space.

[Maurice]

I was thinking it would be good not to have to step up into the cockpit, as you don't in the real thing (I think the floor slopes down ever so slightly as you enter a 737).

Just in case you haven't noticed, a 'real cockpit' is also attached to a real fuselage & the fuselage is attached to real wings, so if you are not planning to do the same, having a step or a slope to enter a simulator cockpit is really not that bad don't you think, especially since real airline simulators have a bridge to enter the cockpit?

Maurice

[Sean]

Thanks for the input guys, appreciated. Gwyn, thanks for the photo, it really helps understanding your comments.

Just in case you haven't noticed, a 'real cockpit' is also attached to a real fuselage & the fuselage is attached to real wings, so if you are not planning to do the same, having a step or a slope to enter a simulator cockpit is really not that bad don't you think, especially since real airline simulators have a bridge to enter the cockpit?

Maurice

Well, I take your point, but I thought if I could avoid it, I would. 

A bridge however, would be cool.

[NAX228]

My base is buildt to have just under 7" beneath the floor, 18cm.
Built in 19mm MDF to fit to the given space I have in my room.