Jump to content

Recommended Posts

  • Replies 1.2k
  • Created
  • Last Reply

Top Posters In This Topic

Posted (edited)

Ka-50 Rudder Pedal Drawings Part 1

 

Almost done now Cat.. Would you look'em over for me? Naturally the mechanics will be added as soon as I get it in house..:music_whistling:

 

drawing1pedalsyv3.jpgdrawing1pedals1567231tu6.jpg

And the PDF-File is here: [ATTACH]23554[/ATTACH]

 

drawing2pedalsqb2.jpgdrawing6pedals1481275xw9.jpg

And the PDF-File is here: Ka-50 Pedals Cross Bar and Center Hub.PDF

 

 

drawing3pedalsdv1.jpg

And the PDF-File is here: Ka-50 Pedal Footrest Sandwich layers.PDF

 

 

drawing4pedalstw7.jpgka50pedalfootrestsandwiwl1.jpg

And the PDF-File is here: Ka-50 Pedal Footrest Sandwich Layers 02.PDF

 

 

drawing5pedalsoi0.jpg

And the PDF-File is here: Ka-50 Pedal Footrest Sides.PDF

 

Are these do-able? Could you build the Pedals from these, or do you want me to change them/add more info?

 

I mean, I made the Pedals simultaniously as making the drawings, so your input is welcome..:thumbup:

Edited by Triggerhappy69
Fixed drawings 08 january 2009

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted

I got arround to making the new back walls for the pit yesterday..!

 

Now the Collective is 100% free of play, and the back walls are made out of MDF.

 

MDF has a much finer surface, and is more easy to make details in with a router..

 

And as you maght notice I have cut out holes for the Fans so they don't protrude from the front like before.. Now I just have to scetch up the details, and cut out holes for the panels on the right side rear wall, and then it's time to paint and re-assemble it..!

ka50collectivebrakepneubq1.jpg

 

ka50collectivebrakepneulm1.jpg

 

ka50collectivebrakepneuct9.jpg

 

 

 

 

ka50collectivebrakepneujk9.jpg

 

ka50collectivebrakepneuzt2.jpg

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted
I GIVE UP..! :cry:

 

(snip)

They are Air actuators (douple action ones). So with these, a 12V solenoid valve and a oneway valve to top up the preasure in the system every now and then (maybe a fillervalve from a car or MC), I will have a Rotorbrake that works 100%..

 

ka50collectivebrakepneuwe8.jpg

 

Here is my initial plan. Loose all the bothersome mechanics and boxes. Use the doubleaction cyclynder and Solenoid valve (blue thingie above it to the right) And the setup looks cleaner. Has no play at all, and (fingers crossed) it works with little or no maintanance..

 

(snip)

Trigger, your work is stunning, and so is the rate of progress you have maintained!

 

A suggestion on the collective / collective brake. Since it appears that you are using a single cylinder (which makes sense) you can keep this even simpler than you described.

 

Leave out the air compressor. Connect the ports as follows:

 

Top cylinder port - tube - solenoid valve -flow adjustment valve - tube - bottom cylinder port

 

Your solenoid valve will be stop flow in the loop, preventing movement. The flow adjustment valve will allow you to tweak the rate that air can pass through the tubing, which will regulate the felt resistance to where you want it. The flow adjustment valve should be one that you can lock down somehow once you have it set where you want it (even if it is just a matter of tightening the packing...). You shouldn't need a compressor as it should work with the air pressure at atmospheric pressure. If you eventually get a small leak, whatever leaks out while you are moving the collective will probably leak back in when you aren't moving it (or when you move in the opposite direction). If you get a BIG leak, well, you need to fix that anyways. ;)

 

No noisy compressor to break down and consume electricity. :)

[sIGPIC][/sIGPIC]

There's no place like 127.0.0.1

Posted
Trigger, your work is stunning, and so is the rate of progress you have maintained!

 

A suggestion on the collective / collective brake. Since it appears that you are using a single cylinder (which makes sense) you can keep this even simpler than you described.

 

Leave out the air compressor. Connect the ports as follows:

 

Top cylinder port - tube - solenoid valve -flow adjustment valve - tube - bottom cylinder port

 

Your solenoid valve will be stop flow in the loop, preventing movement. The flow adjustment valve will allow you to tweak the rate that air can pass through the tubing, which will regulate the felt resistance to where you want it. The flow adjustment valve should be one that you can lock down somehow once you have it set where you want it (even if it is just a matter of tightening the packing...). You shouldn't need a compressor as it should work with the air pressure at atmospheric pressure. If you eventually get a small leak, whatever leaks out while you are moving the collective will probably leak back in when you aren't moving it (or when you move in the opposite direction). If you get a BIG leak, well, you need to fix that anyways. ;)

 

No noisy compressor to break down and consume electricity. :)

 

 

A reduction valve... Hmmm...? That was i brilliant idea..! I'll go get my hands on one right away..!

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted (edited)

The only issue i can see is that air is not that dense, and its easely compressable (think shock absorber), ie, you will have some give/flex and you will be able to move the the collective up and down without releaseing the lever. use a fluid instead (brake fluid or car coolant) that is much more dense and will not give a millimeter... abit more messy though, you will need a one way valve and a reservoir and a t-coupling as well.

Edited by Swetrekki
Posted
The only issue i can see is that air is not that dense, and its easely compressable (think shock absorber), ie, you will have some give/flex and you will be able to move the the collective up and down without releaseing the lever. use a fluid instead (brake fluid or car coolant) that is much more dense and will not give a millimeter... alot more messy though.

 

I was thinking much the same. However, it appeared to me that he wanted to go with air, since his previous configuration (modified door dampeners) had fluid leakage problems.

 

The air-based system may give him a solid enough feel (after all, he probably isn't planning on yanking on the collective with the brake engaged, so as long as it holds position under its own weight, he may be happy). If not, I don't see why he couldn't fill it with an appropriate fluid, as long as he has no system leaks. :)

  • Like 1

[sIGPIC][/sIGPIC]

There's no place like 127.0.0.1

Posted (edited)

I just think that the momentum that the collective arm is giving him would compress the air to much, and seeing as he didn't like the feel of the luggage strap that he was using in an earlier version i figured he is getting to be a bit of a perfectionist (and i love him for it) he'd be disappointed when it wouldn't be a more solid feel to it....

 

anyway, its not as fancy as your cad renderings but here is what i mean, and it is easy enough to build without leakage if you dont use modified air cylinders :P

pipe.JPG

 

edit: an easy enough way to test it would be to connect the appropriate length of air tubing to the cylinder and connect both ends fo the tube to the cylinder, that would give you and indication of the compression.

Edited by Swetrekki
second thoughts...
Posted

... What if I used a heavy duty cyclepump to compres the air in the system?

 

Would that make it more rigid?

 

And is it possible for me to run some kind of thin fluid in the air-system if I'm not satisfied with just air?

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted
... What if I used a heavy duty cyclepump to compres the air in the system?

 

Would that make it more rigid?

 

The more the air is compressed by external means (your cycle pump), the more difficult it will be for your collective stick to compress it (by attempting to move the collective with the brake engaged). But it will still be a compressable gas, so it will be a matter of degree. Plus, that puts you back to more complexity/noise/maintenance/power consumption.

 

And is it possible for me to run some kind of thin fluid in the air-system if I'm not satisfied with just air?

 

I would say so. In fact, I opined as much earlier. ;) Just make sure you don't have air leaks before filling with a liquid. Make a solution with dishwashing soap in water... With power off, squirt it slowly upon your various tubing/fitting joints (while moving the collective up and down to create pressure in the system.... If you don't see bubbles, you aren't seeing an air leak. Or, just save yourself the bother and skip that if it looks/sounds like too much of a hassle.

 

If you decide to add liquid, make sure it is compatible with your piston ring(s) material. A dielectric fluid (ie. mineral oil) would probably be a wise choice in light of all the electrical items in your pit.

[sIGPIC][/sIGPIC]

There's no place like 127.0.0.1

Posted

..ok... It seems that if I pump A LOT of preassure in the system it is close to the rigidity I was going for.. But not quite..?

 

So I will try running a thin mineral oil in the system. But thaty opens another question. Will I ned to build the storage tank and one-way valve like Swetrekki made a drawing off?

pipe.JPG

 

And what is the puspose of this tank?

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted (edited)

well the purpose is that its a whole lot easier to fill it, and clear off any air bubbles in the system, and make sure that it stays filled, even if there is a minute leak.

 

just think of it as the breaking system in a car, its the same principle.

 

 

Edit: come to think of it you might verry well skip the tank and the one way valve and just put a cut off valve there instead. it's cheaper and easier i guess.

Edited by Swetrekki
Posted

Alternatively, if you are confident that you can make the connections leak-free, you could go with fill and vent valves (or cap-able "tees" and have a closed loop system:

370844356_CBSketch.thumb.jpg.8a4d4b8027123d397404792f93969620.jpg

[sIGPIC][/sIGPIC]

There's no place like 127.0.0.1

Posted

Honestly, if you are going to go with fluid, then a reservoir is probably going to be more convenient.

 

A simple way to get an idea whether an air filled system would be solid enough would be to just cap off both of the cylinder connections, and then see if the cylinder/collective have any "give" that you can notice. If there is no noticeable give, (and if you keep your tubing volume small), then the simple, cylinder - tube - solenoid valve - adjustment valve - tube loop should be adequate, and easier.

[sIGPIC][/sIGPIC]

There's no place like 127.0.0.1

Posted (edited)

CyBerkut, i agree.

edit: an easy enough way to test it would be to connect the appropriate length of air tubing to the cylinder and connect both ends fo the tube to the cylinder, that would give you and indication of the compression.

 

And i had a bit of a rethink, that reservoir solution is what i used on a water cooling rig, but you probably dont need it come to think of it. The easy way to start out with this would be to build it something like what Cyberkut suggested. it ought to work well enough

 

And if you are gooing to use it you still need a bleed valve otherwise you would still have trapped air in the system = bad thing, just like on a car

Edited by Swetrekki
  • Like 1
Posted

Quick update:

 

I filled the system with hydraulics oil, and got rid of as much air as I could before sealing the system and testing..

 

And IT IS BEAUTIFULL...! I can not belive what a difference using "real" actuators and a good On-Off valve makes.

Now when I release the collective brake handle it just STOPS..! And the only play I can detect (and I had to really look for it) is in the 0.04mm gap between the threaded rod that the Collective turns arround and it's ball bearings..

 

So next now is the final sanding, some paint and re-assembling the Left Rear Wall.

 

Thank you so much for your input guys..! With your help I have finally got the Collective that I was aimimg for..

 

... drinks are on me..!

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted

.. oh yeah..! I almost forgot..

 

I did the leak-test with soap that you discribed.. And it came out with nothing..!

 

And with a 6mm tube there is no need to have a reduction valve either.. Actually it's just perfect..

 

But I will add the resarvoir tank and one-way valve like you said..

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

Posted

thats really great news trigger, you inspired and helped loads of us so its only fair that we help you ;)

 

Oh, there is one more thing you can do... PICTURES PICTURES PICTURES :)

Posted
thats really great news trigger, you inspired and helped loads of us so its only fair that we help you ;)

 

Oh, there is one more thing you can do... PICTURES PICTURES PICTURES :)

 

 

:music_whistling:.. They are coming mate..

 

Since I had to take the collective mech apart anyway I decided to paint the whole thing now.. I just know that if I didn't It wouldn't get done.

 

Pictures of Ejection Seat with Left and Right Rear Wall attached and painted will be my next update..

 

.. now where did I put those hall-effect sensors anyway..:cry:

"But (504)Brewber said they were'nt friendly.. So I took'em out.!"

[sIGPIC][/sIGPIC]

 

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...