Cleaning up the Alpha Sport 450

On getting back home with the Alpha Sport 450 wing, I took a good look at my Alpha Sport. Crikey, I have neglected it... Spent some time fixing and cleaning up a few issues.

The motor mount did take a beating. The sides of the compartment are warped out, the motor mount all twisted. I removed the motor and ESC for the first time is some 15 years.

The firewall is a bloody mess. When I say that up until recently it had never been crashed, while true the OEM front gear wasn't sturdy for non-paved style runways and ripped out. I installed a much sturdier one and have had no issues since, but this required building up the firewall. Its a mess and I think the mount blind buts are loose and the wood they are secured to unreliable. The easiest thing to do was to fabricate a new firewall to epoxy over the old one. Curiously this works without interfering with the land gear mount. I installed this and tomorrow will reinstall the motor. I trimmed the mount extenders to accommodate the loss if depth. Changed the prop, pretty sure thismone is at least 10 years old and it looks it. I have a gray APC 10x7 on hand but have a couple black ones coming soon. Tomorrow we'll see what sideways BS will surely challenge me, and get the engine back on. Then cleanup and repair worn cote, reinstall the wing and yes, it may very well be the first plane I fly at Flying Tigers in Derry, NH.

Alpha Sport 450 wing repairs are done!

 John has completed the work on my demolished Alpha Sport 450 wing and the quality of the work is stunning...

I am so lucky to know John and am so grateful for his time, skill and craftsmanship. A sixer of Guinness will be yours soon!

Thanks, John!

RF Evolution, Spektrum WS2000 Sim Dongle, Spektrum DX7s and a decade of mystery solved in a few minutes...

 

              

Ultrastick Wiring: RCEXL Opto Kill Switch is NOT an BEC

Spent some time in a conversation with Google Gemini (their AI) and learned a lot I hope I knew and forgot about how the opto kill switch is not an IBEC.

The diagrams for the RCExl Opto Kill Switch look like this:

The RCEXL Optical Kill Switch does two things. It uses a light junction to separate the hard wire electrical connections so the 20,000 volts of noise generated by the spark plug do not flow back into the receiver and electronics interfering with them or frying them altogether, AND it serves to kill the power to the ignition. Power to the OKS passes through, so my 2S 7.4v LiPO would send up to 8V to the ignition, if the light sensor inside the is on. Here's how Gemini explained it:

The RCEXL unit has two sides that are "optically isolated" (connected only by a beam of light inside the chip) to prevent electronic interference from reaching your receiver:

1. THE RECEIVER SIDE: It plugs into your receiver to  get a signal and a small amount of power just to run the internal LED and the "gate."

2. THE IGNITION SIDE: It has a "Battery In" and an "Ignition Out" lead. You must plug a battery or regulator into the "Battery In" lead.

What happens when you flip the switch:

1. Switch On: The RCEXL unit closes the circuit, allowing power from the ignition battery to pass through to the ignition module.

2. Switch Off: The unit breaks the circuit, cutting off power and killing the engine.

I had my circuit like this:

This works, but apparently it allows interference noise hardwired back into the circuit. Options are a separate battery (two battery system, nice in big airplanes) or one battery and an BEC. Note that with this setup the RCEXL unit LED did not light up... so I think the RCEXL is bad.

Above is how I will be doing this circuit. I purchased a RCEXL Opto Kill Switch with BEC (see below). from Valley View RC. Curiously they are the only place that carries this.

Apparently this (above) is the OPTIMAL way to do this. It protects the circuit by filtering out the feedback, and offers a kill switch. I have one of these on the Pulse XT60 (need to see if I also have a RCEXL switch as this would be redundant).. Pictured below is the Tech Aero one I have, and is most recommended, in that its one of the few out there. Problem is its over $70 delivered, which is why I went with the RCEXL one.  IBEC's, especially one with a LED indicator light, are very hard to find, and nothing under the Tech Aero price.

I did drop by the workshop to check a few things, like do I have a IBEC. I have a UBEC but Gemini did not recommend this with the kill switch, and it added more complication to the circuit. I built a little holder to secure the receiver pack, and removed the RCEXL kill switch. I will likely return the one arriving today from Amazon as I don't need it, and am waiting for the one from Valley View, coming by some dude on a bike from Indiana, maybe 3-5 days?  Tomorrow I may try firing up the engine without the kill switch, wiring in directly to the battery through a 5V regulator. I am concerned that the touchy EVO 10cc will try what little patience I have left (hence today a day of rest).

This build has been no fun at all...

Seriously. This is my third build of the Ultrastick 10cc and this one has been one pain in the ass after another. It has been three days of total immersion: I get started and hours go by before I realize it. Today was build final, but I have, yes, some issues to resolve before its a wrap.

My shabby workshop in my garage from the1700's 

(yeah, my apartment is in a house over 250 years old).

The tail assembly looks great, but it was one little thing after another. It starts with my habit of replacing CA hinges with pin hinges. Lets just say I should have stuck with the CA hinges. Despite perfect dry fitting, once the epoxy went on nothing went as planned. I am honestly am some what shocked at how clean it looks. The discerning reader will note the cote patches and kindly say nothing about them...

I was so annoyed at the process I was prompted to put this missive here as a reminder. See that space just aft of the vertical stabilizer? There was one in the front too, with the deep attachment point in between. Seems the epoxy lifted it and let it slide back a couple of mm, despite my taping the entire thing down. This, of course, placed the rudder-fin joint back a couple of millimeters, making the tail assembly a couple of mm aft, which it bore grudgingly.  Yeah, its been that sort of build...

The dual switch assembly went in, also with a few minor issues. One of which I found the wiring for both switches to be Y'd together into one Futaba style connector to the receiver. One is supposed to be receiver, the other ignition. This switch came from the last Ultrastick. Did I do that? It does have one Y;d lead for the lead from the battery to the switches, but the outputs should be separate. This issue became obvious when I was trying to wire in the optical kill switch: there was no lines from the switch to a connector for the kill switch power input. If I did that weird Y, kudos as the solder work was so perfect I wondered it if came that way, how could that possible work, and how did I set this up last time? I am still not sure I know WTF is happening...

At the end of the day this is what I had, the optical kill switch not installed at this pic.

Because this is only 17 seconds of flaming hotness You Tube made it a short, and I can't figure out how to get teh embed code for a short, so you'll have to click the pic for the video. Sorry for my tone, I had had enough of cockamaemee BS.

Then there was this little gem. I expected a tube from the electronics bay to the rudder control rod exit point, and likewise on the elevator side. The first segment of the tubes is visible, but the wire hit every frame as if it was NOT in a tube. Took forever. I had no idea where it would come out, but the rudder, then elevator exit points popped thru when I finally got the rods there. That likely was because there was a least a tube at the end, or it would never have exited. WTF? Well, it works... The control rods are cut to exact length so you have to use the metal clevis provided. Which led to this problem...

             

Sorry for the video quality, doing a two-handed thing one-handed. None of the metal clevis's fits tightly enough. I had to crush them all down more tightly then screw them in, and secured them with a littler CA (one still came apart today).  FFS. This was true for all of the small gauge clevis's, I didn't use the large ones.

So, that was yesterday.

Today wasn't as bad, but time flew. I went in at around 930a, looked up and it was almost 2p, blinked and it was 630p. Hadn't even bothered to stop for lunch (and I had skipped breakfast). 4

I finished up installing the electronics, (will get a pic tomorrow), and mounted the engine. I installed the optical kill switch. When I turned on the power to the switch the LED didn't light up. Checked to make sure my switch assignment was good (Gear to H button on my iX12). Checked to make sure the ignition switch worked and had power by swapping it to the receiver. It did. So maybe the LED is bad or the kill switch is, though one means the other as I don't have a spare LED. So I ordered a new one that will arrive tomorrow. I don't think the status of the electronic ignition matters, but if the new switch doesn't work, maybe? All of this, mounting the engine, unmounting it as I drilled the throttle control rod tube whole too high, remounted it. I also painted and gas proofed the firewall. All of this seems to have take more time than it should. 

I did take a moment to paint the prop tips. I did the classic red strip on white background, but it didn't go well and re-did it as just white. Not sure I will bother with the red center stripe.

I pulled the DC-3 from the loft. Haven't flown this in years... started thinking about it last night. It doesn't like grass for take-off and landings, so I haven't been able to. It tended to lift off before it had quite enough airspeed to stay aloft because of the grass. Now that I have access to a geotex runway, that may not be a problem. Its a simple foamie. Pic tomorrow.

And now I am starving...

Tomorrow I will install the new optical kill switch. I hope it just works. Then will come the challenge of getting the EVO 10cc engine to start, run and tune easily... not looking forward to that. I may take a day off depending on weather and go fly or sail or both. 

Wow... John Hayes rebulids the Alpha Sport 450 wing

 

This was the state of my Apha Sport 450 wing after my controlled flight into a line of trees that proved closer than advertised. The right wing leading edge had a fractured as martial loss not as impressive but seious as well. Repairing this requires skills far beyond mine, yet I was loath to abandon what is my first true rc aircraft.

On a whim I approached John Hayes, a friend from SNHRCC. I knew he is a master builder, and I felt if there was any hope,i t would be him. He agreed, and a couple of days ago I dropped it off (and experienced the wonderland that is his workshop for the first and I hope not last time). Two. Days. Ago.

He sent me these pics today:

The right wing.  Can't even tell where the damage was.

This is the repaired left wing. Are you kidding me? Its literally new. This is a rare level of skill.

He will cote them and let me know when to come-back it up. I just can't wrap my head around how well this repair has come out. I am just so impressed by John's skills as a builder, just so please with the outcome here.

Thank you, John. You are giving me my baby back.

My Alpha Sport 450 back when I got her over a decade ago. 

Sadly, like many good things, no longer produced.

MX2 and Cubby are up

 

I described the debacle that was "simple repairs" to my Hacker MX2 in last night's post. I had to replace the bad aileron servos, and it required a lot more than it should have. The new servos required new servo arm extensions, which I had to manufacture. Overnight the CA did bond, and I easily put a single screw into each to further secure them. Once I got that done, the rest was simple. A little time to make sure the ailerons were level and zeroed, and everything is grand. No more jiggy shit. Returned the gyro after having to make a better bed to secure it in after mining the foam to get the servo wire extensions in place.  That rectangle under the fuse is where I had to cut to gain access to pass the wires.

Staying in the spirit of the theme, the Cubby decided that there was no adventure in simple. It easily bound, that wasn't the problem. The problem was the connector was a massive EC5, which in my ignorance I used when I first started in the hobby (the Cub is one of my first planes, over a dozen years old).  I have since changed to EC3 on my 4S and smaller batteries and aircraft. 

The problem with EX connectors is that some are "push in ", and some are "pull thru". To seat the metal connector into the blue plastic housing, you either push it in, or pass the wire thru the connector before soldering the metal connector, and then pull it back in to the plastic housing to lock it in place. I sadly have a mix of them. And even if you get that right, being g able to push or pull it to lock it can be seriously difficult. When it is, I find heating the connector and letting the heat soften the plastic as I push (or pull) it into place. This usually works. Its one of those simple things that is just never simple. I wonder if XT connectors have a similar problem? I have never used them. Traxxas connectors difficulty is getting the solder to stay bonded to the metal. I now have a bottle of flux that might help with those. I use them on my heli receiver packs for nopartucular reason.

So I had to replace the EC5 with an EC3. Went thru a couple just trying to get the damn things to lock and stay. I also ended up extending the wires between the ESC and the battery end connector. 

Patched a few hangar rash issues in the cote, and she is once again shiny as she can be. There are some areas of melt wrinkled corners of cote that I can fix later.