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Flap control with Infinity Stick

Nihon_Ni

Well Known Member
I've searched all through the threads here, and this topic has been discussed a few times over the years, but unfortunately most of the "see the details in this picture" picture are missing, so the discussion wasn't much help.

I'm building an RV-8, I have an Infinity stick grip and a stock Van's flap motor. I know I need some type of relay between the flap switch on the stick and the motor, but I'd like some feedback on how to proceed. My switch is an (ON)-OFF-ON variety with the spring loaded direction in the flaps down direction.

Here's the options I'm considering, but I'm sure there's options I've missed.

1. Use two relays and two micro switches and wire it according to Bob Nuckolls' drawing.

2. TCW Flap controller.

3. Van's Flap Positioning System

Any feedback on these options or others?

Thanks,
Rob
 
I have infinity grips with (on)-off-(on) toggles for my flap switches. I originally ran my flaps via my VP-200 but when it went Tango Uniform I opted for the TCW controller. It has worked just fine. My only advice is if you go the TCW route is invest in a ferrule kit and crimper to terminate the wires. The TCW uses those connectors with the little screws that clamp on the wire which don’t work well with stranded wire. Without a ferrule the wire tends to slip out of the connecter especially when you are futzing with multiple wires in tight corners.
 
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I've searched all through the threads here, and this topic has been discussed a few times over the years, but unfortunately most of the "see the details in this picture" picture are missing, so the discussion wasn't much help.

I'm building an RV-8, I have an Infinity stick grip and a stock Van's flap motor. I know I need some type of relay between the flap switch on the stick and the motor, but I'd like some feedback on how to proceed. My switch is an (ON)-OFF-ON variety with the spring loaded direction in the flaps down direction.

Here's the options I'm considering, but I'm sure there's options I've missed.

1. Use two relays and two micro switches and wire it according to Bob Nuckolls' drawing.

2. TCW Flap controller.

3. Van's Flap Positioning System

Any feedback on these options or others?

Thanks,
Rob

I did #1 long before the other two options were available. In 12 years and 1600 hours of flying, it has been flawless. It?s also relatively inexpensive and was easy to wire.
 
#1, no microswitches

I've searched all through the threads here, and this topic has been discussed a few times over the years, but unfortunately most of the "see the details in this picture" picture are missing, so the discussion wasn't much help.

I'm building an RV-8, I have an Infinity stick grip and a stock Van's flap motor. I know I need some type of relay between the flap switch on the stick and the motor, but I'd like some feedback on how to proceed. My switch is an (ON)-OFF-ON variety with the spring loaded direction in the flaps down direction.

Here's the options I'm considering, but I'm sure there's options I've missed.

1. Use two relays and two micro switches and wire it according to Bob Nuckolls' drawing.

I used the 2 relay Aeroelectric method without relays. The flap actuator has internal limits. I rigged mine so that the upper limit is reached at the fully retracted position. The lower limit will prevent over extension. When it hits the limits, the motor will run free and the flaps stop moving. Release the switch and you're done. It won't hurt to run the motor for a few extra seconds until you can spare a moment to visually confirm the flap position.

Ed Holyoke
 
I have the Infinity grips and had an on-off-mom switch put in. I also used Infinity's flap and trim relay board. Works great for the past 575 hours. I did rig an up limit switch, so when I retract the flaps, I just flip the switch on the switch up and the limit switch opens the circuit when the flaps are full up. Works fantastic.
 
isolate rear grip

One mode to consider in your design...

If you have flap control switches on front and rear grips, make sure that you include an isolation switch to disable the rear stick.

If you use up-off-(down) in both seats, if the rear (pilot/passenger) accidentally flips the rear switch up, you will be doing a flaps up landing.

We have a rear isolation switch installed, but didn't consider this case and it happened. Obviously not a critical failure, but it could be in unfortunate circumstances.

The 'fix' is to either add 'isolate rear stick' to downwind check, or install a (up)-off-(down) in the rear seat.

Regards,
Chris
 
Similar to Todd I have a (ON)-OFF-(ON) set up. I am using the VPX though to manage positions. It's been great, about halfway through I changed from a relex, 10, 20, 30 degree setup to reflex, trailing, 1/2 and full configuration. Being able to make those adjustments fairly easily is helpful.
 
Similar to Todd I have a (ON)-OFF-(ON) set up. I am using the VPX though to manage positions. It's been great, about halfway through I changed from a relex, 10, 20, 30 degree setup to reflex, trailing, 1/2 and full configuration. Being able to make those adjustments fairly easily is helpful.

I also have VPX installed in KELLI GIRL, and use it to control my flaps. My Infinity sticks? flap toggles are spring-loaded in both directions back to the center ?off? position. By momentarily bumping the switch down once, VPX takes the flaps down to half flaps. Then, another bump gives me full flaps. Bumping the switch up brings the flaps up to 0. Any time the flaps are traveling, I can stop their travel with another switch bump. By pressing and holding the switch down or up, the flaps will move until I release the switch (for setting some flap setting other than half or full, like 1/4 flaps for a soft-field takeoff).

I also 100% concur with the need for a kill switch...a ?grandfather? switch, my wife calls it. Those pesky kids...;)
 
This is key

My Infinity sticks? flap toggles are spring-loaded in both directions back to the center ?off? position.

Excellent idea.

Mine was NOT set up this way by the original builder. It was spring-loaded to return to center from the down position, but would stay in the "up" position. And (just as importantly) it had no gadget or circuitry to turn the motor off once the flaps were all the way up.

So you can probably guess what happened: I knocked it once with a gloved hand at night, which caused the flap motor to run "up" for about 45 minutes. Burned the motor to a cinder.
 
Excellent idea.

Mine was NOT set up this way by the original builder. It was spring-loaded to return to center from the down position, but would stay in the "up" position. And (just as importantly) it had no gadget or circuitry to turn the motor off once the flaps were all the way up.

So you can probably guess what happened: I knocked it once with a gloved hand at night, which caused the flap motor to run "up" for about 45 minutes. Burned the motor to a cinder.

I guess I should have been more clear in my first post about the toggle's action. An action in parenthesis means momentary so (on)-off-(on) means momentary (ie spring loaded) in both the up and down positions with return to center which is off.
 
Having two relays is dirt simple. Had that on the RV-8A for years. You do need to install an up limit switch to cut off power to the motor when the flap is all the way up - if not the motor will just continue to run. Not healthy for it.

After flying with the Van?s Flap Positioning System on the RV-10 I decided that was a far superior way to go. Another one got back fitted on the RV-8A and it is being install on the new RV-8.

Agree with the previous post on having a ?who is in control? switch for planes with two stick grips. I use a locking DPDT. One side of the switch isolates the common ground for the flaps, the other side the common ground for the trim hat.

Carl
 
Thanks for all the input. I should've mentioned, but I don't have a second flap switch in the back seat, so no need for an grandfather isolation switch, although I love that name!

For those who do have up or down limit switches, where did you mount them? Any photos would be helpful.
 
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I used the 2 relay Aeroelectric method without relays. The flap actuator has internal limits. I rigged mine so that the upper limit is reached at the fully retracted position. The lower limit will prevent over extension. When it hits the limits, the motor will run free and the flaps stop moving. Release the switch and you're done. It won't hurt to run the motor for a few extra seconds until you can spare a moment to visually confirm the flap position.

Ed Holyoke

Ed, I think you meant you didn't use micro switches, yes? How did you adjust the flap linkage to make sure the internal limits were reached as the flaps reached their limits? Perhaps it's simpler than I anticipate, but if you have more info that would be great!
 
Having two relays is dirt simple. Had that on the RV-8A for years. You do need to install an up limit switch to cut off power to the motor when the flap is all the way up - if not the motor will just continue to run. Not healthy for it.

After flying with the Van?s Flap Positioning System on the RV-10 I decided that was a far superior way to go. Another one got back fitted on the RV-8A and it is being install on the new RV-8.

Carl

Thanks Carl. I am considering it, but the primary obstacle at the moment is the price. I'm trying to decide if it's 8 times better than the Nuckolls' roll you own method. You decided it was worth it, so that's a helpful data point. What was the reason that made you retro fit the 8A? Is it the "set and forget" feature of the system?

cat-med_fps.jpg


Where do those aluminum brackets mount, do they go in the motor and measure the arm movement? Thanks!
 
I have infinity grips with (on)-off-(on) toggles for my flap switches. I originally ran my flaps via my VP-200 but when it went Tango Uniform I opted for the TCW controller. It has worked just fine. My only advice is if you go the TCW route is invest in a ferrule kit and crimper to terminate the wires. The TCW uses those connectors with the little screws that clamp on the wire which don?t work well with stranded wire. Without a ferrule the wire tends to slip out of the connecter especially when you are futzing with multiple wires in tight corners.

I haven't heard of the ferrule crimps, so that was new info for me. I spent some time researching them as I have a few other components that use the screw type connection. Where did you buy your ferrule tips? All the ones I found from a Google search look like the automotive type that I learned to avoid in the Aero Sport Workshop.
 
Thanks Carl. I am considering it, but the primary obstacle at the moment is the price. I'm trying to decide if it's 8 times better than the Nuckolls' roll you own method. You decided it was worth it, so that's a helpful data point. What was the reason that made you retro fit the 8A? Is it the "set and forget" feature of the system?

cat-med_fps.jpg


Where do those aluminum brackets mount, do they go in the motor and measure the arm movement? Thanks!

The rod has notches that activate micro switches in the saddle bracket. The saddle bracket and rod bracket are mounted on the flap motor and motor drive rod. Take a look at Tom?s RV-8A on how he did this.

The value of this unit is three fold:
- Eliminates the need for reversing relays if using a standard stick switch
- Eliminates the need for at least the up limit switch mounted at the motor (and the pain of making brackets to mount them so they hit ?just right?).
- Allows for ?push once? and the flap moves down to next position as well as ?flip up? and the flaps come all the way up.

Is it worth it over a couple of $5 relays and a $10 limit switch? For me it is. You need to make this decision for you.

Reminder - there are different units for the various RVs. Order the right one for you.
Carl
 
Excellent idea.

Mine was NOT set up this way by the original builder. It was spring-loaded to return to center from the down position, but would stay in the "up" position. And (just as importantly) it had no gadget or circuitry to turn the motor off once the flaps were all the way up.

So you can probably guess what happened: I knocked it once with a gloved hand at night, which caused the flap motor to run "up" for about 45 minutes. Burned the motor to a cinder.

When I originally ordered my Infinity sticks, the toggle switches came configured just like yours. I contacted Infinity and ordered the switches spring-loaded both ways to center (like Todd's). It was an easy retrofit. BTW, Infinity included a socket wrench extension for the switches, with the socket's outer diameter narrowed down to fit into the grip's tight spaces.
 
I haven't heard of the ferrule crimps, so that was new info for me. I spent some time researching them as I have a few other components that use the screw type connection. Where did you buy your ferrule tips? All the ones I found from a Google search look like the automotive type that I learned to avoid in the Aero Sport Workshop.

Rob, I bought my kit off Amazon. Like most tools there?s a range of quality. This one is most likely on the bottom end but it works.

https://www.amazon.com/gp/product/B06XCZC89W/ref=ox_sc_act_title_1?smid=A1YLL9HRCJCGO9&psc=1
 
Ed, I think you meant you didn't use micro switches, yes? How did you adjust the flap linkage to make sure the internal limits were reached as the flaps reached their limits? Perhaps it's simpler than I anticipate, but if you have more info that would be great!

Yeah - no external microswitches. I have the (mom)-off-(mom) switch in the Infinity grip. I put a second switch on the panel for co-pilot. If both are actuated, flap motor doesn't run. No need for lockout. As for adjustment, I clamped the flaps where I wanted them, ran the flap motor full up until it spun free, and adjusted the rod end bearing in the flap actuator to line up with the arm. Easy. I believe I got something more than the specified 40* of down travel to where the actuator spins free. I'm not worried about that. It works great.

It takes something like a count of seven or eight from one end to the other. For landing I trim to 85kt and give the flaps about a three count. On short final and slowed and trimmed to about 75kt, I'll put the rest in as needed. I run them perhaps a few more seconds than I think I need if I don't have time to look at the position indicator or the flaps themselves. On a touch and go, I will run them for about a count of eight or ten to make sure they are all the way retracted and then add power and start trimming. I'll glance at them to confirm when I have time.

Ed Holyoke
 
Trim and flap relay boards

Funny you are mentioning this. I am in the process of building my own relay boards. I did some real rough ones with off the shelf components as a proof of concept and they worked really well. I followed AeroElectrics diagram of JD Newmans Infinity Aerospace page.

After some success I decided to build a custom PCB. Much more stable and compact. I just ordered it so it will be about 10 days before it gets here.

Here is a pics of it that shows the traces (mostly).

oJX.jpg



Here is a silk screen of the top pcb.

oJj.jpg



Here is proof of concept version one with off the shelf parts. Works good but crude.

oJB.jpg


Here is the business side of a hand made pcd relay board. It is hotglued to thin Lexan.

oJS.jpg


The bottom boards have the yellow wires that control the motors. The green wires go to the infinity switch (that go to ground). Red+/Blk-.

The newer custom made PCB on order has much higher end relays and diodes in it and can hand up to 5 amps so it will be good for the AIL, ELE and Flap motors. It also has reverse polarity diode protection on it.

I apologize to the OP if there is a feeling I am OT. If there is an interest in a follow up on how the custom PCB works you can PM me. Or as here if it is OK with the OP.

Charlie Rosenzweig RV6a
with Honda engine
 
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