Roban AH-1W Cobra 700 Size Scale Helicopter

[sfcfury]

Yea it seems like a lot of the navigation lights on aircraft have multi function positions... Yea I feel like I've eaten away most of the inside of mine with the dremel... and I think that's basically the issue I ran into with the tail push rod... the mechanics were aligned properly as I could get them, but once I put the vertical boom into the tail, the push rod rubbed the side... really seems like the control arm should be a few mm longer anyways...

[F106DeltaDart]

Thanks sfcfury.....it appears those tail lights begin to blink after the Cobra landed. Not strobes, but looked like they did blink on and off?
Speaking of lights, had my first Dremel job on this AH today. Was fitting the stub wings to the fuse after installing the lights & pylons when I discovered the stub wing “socket” on the port side was molded wrong, or either the port side stub wing is supposed to be thinner & shorter than the starboard side. Had to Dremel the inner edge of the wing 1/8” all around to get a tight fit in the socket. I recessed this “ledge” about 1/8” also so it doesn’t show. Was good exercise, but that’s a pretty big defect in the kit engineering! I wouldn’t even mention it & am accustomed to minor fitting, but this thing wasn’t even close!

Here is the lightning layout from the Flight Manual. The nav lights have 3 settings, flash-Off-Steady. So both flashing or steady would technically be scale.

[PawPaw]

Thanks sfcfury.....it appears those tail lights begin to blink after the Cobra landed. Not strobes, but looked like they did blink on and off?
Speaking of lights, had my first Dremel job on this AH today. Was fitting the stub wings to the fuse after installing the lights & pylons when I discovered the stub wing “socket” on the port side was molded wrong, or either the port side stub wing is supposed to be thinner & shorter than the starboard side. Had to Dremel the inner edge of the wing 1/8” all around to get a tight fit in the socket. I recessed this “ledge” about 1/8” also so it doesn’t show. Was good exercise, but that’s a pretty big defect in the kit engineering! I wouldn’t even mention it & am accustomed to minor fitting, but this thing wasn’t even close!

[sfcfury]

I have yet to see a video of a AH 1W with strobes back there... but steady on lights I am attaching a link to a video. There's are several lights on that cluster as well, IR lights for sure, but can't tell if any would be strobes.

[PawPaw]

Saw a AH 1W video that had a pair of flashing strobes on the tail. Is that scale? Looks good but won’t do it if not.

[PawPaw]

No, they don’t like sliding in or out for sure, do they? Got ‘em installed & tightened down. Been struggling w/my common sense today & resisted getting out to buy some wood for a test bed ( copy yours, of course). Mechanics are ready & FBL is programmed correctly, I think. Didn’t really plan to start detailing it out yet but this Corona virus keeping my 68 y/o butt indoors. So, detailing it will be.

[sfcfury]

Gotcha... well if your skids were anything like mine, I would have to do something very dramatic (pretty much catastrophic) in order for them jokers to move... in fact I almost forgot to put the screws in b/c I had it 'dry fitted' so long lol...

[PawPaw]

Yellow dot is where the hole needs to be with skid pushed in against the stop.

[PawPaw]

No, the holes predrilled in the skids for the mounting screws. They’re off about 1 screw diameter & don’t match the mounting block holes inside the fuselage. I think my best option will be to JB Weld the old holes & redrill. I could make it fit by trimming the inside ends of the skids but I don’t think they’ll push in any farther to get the existing holes aligned.

[sfcfury]

Another Cobra question: My skid’s mounting holes are off & won’t line up with the predrilled ones in the fuselage. Not a big deal & easy to redrill the skids, but want to get the skid width dimension right. I’m pretty sure there’s a stop inside the fuse that limits how far each one can be inserted but curious what the width measurement is for the Cobras that fit originally? Thanks!

Really... are you talking about the holes inside the fuselage to secure the skids, or the ones on the side of the fuselage that the skids go into? I know pushed my skids in till the stopped... it felt like i was gonna break something b/c the scraping sounds as they kept going in further... but finally they hit the stop.

[PawPaw]

Another Cobra question: My skid’s mounting holes are off & won’t line up with the predrilled ones in the fuselage. Not a big deal & easy to redrill the skids, but want to get the skid width dimension right. I’m pretty sure there’s a stop inside the fuse that limits how far each one can be inserted but curious what the width measurement is for the Cobras that fit originally? Thanks!

[OV10]

The only one out there that I know of is this, and its been out of stock for over 6 months now: https://hobbyking.com/en_us/turnigy-...-switch-1.html

I snagged about half dozen a couple years ago at about $5/pc and have 1 left in inventory. Too bad that HK can't get their purchasing management act together because these are really good devices.

[sfcfury]

Looks good Delta! I like the fpv idea ... your the type we need in here lol... with all the actual skills! I just used some mirrored tape on my nose... and while I had definitely thought about make the gun turret rotate, didn't really trying to sync them up.

[F106DeltaDart]

Ohhhh, F106...you’re sorely tempting me to dumb thumb one of my foam jets just to gut the innards. That gun needs a parts kit (hint) for sale to us folks short on imagination.
sfcfury...could you vid that sound when it’s up & ginning? I’ve heard some on ‘tube but would like to hear how your installation sounds.

Thanks PawPaw, Unfortunately, I just don’t have the time to kit something for gun. It really isn’t too bad to build, especially if you have an old Trex 450 frame to canibalize. I'm sure someone with more talent could come up with a 3D printed solution that is more elegant and scale looking. Mine is pretty much just built out of leftover parts I had lying around in the shop.

I did get it mounted to the aircraft today. Still waiting on a 180 deg servo for gun azimuth. This will also tie to the FLIR so that the movements are synchronized. Tomorrow I’ll start to work on getting the mechanics together. I also started some detail work on the FLIR. I couldn’t stand the black painted lenses, so I cut out the left opening, and added some clear plastic with a mirror film on the right. For the left side, I’m hoping to embed a small FPV camera inside for an observer to operate. They would be able to control the gun and FLIR during flight. Should be great for handing off to kids and friends during fun flys.

[PawPaw]

Ohhhh, F106...you’re sorely tempting me to dumb thumb one of my foam jets just to gut the innards. That gun needs a parts kit (hint) for sale to us folks short on imagination.
sfcfury...could you vid that sound when it’s up & ginning? I’ve heard some on ‘tube but would like to hear how your installation sounds.

[sfcfury]

With my sound card, I have a sound 2 option... I haven't finished playing with it yet, but my intent was to have an APU sound on that channel... and I wanted to tie my lights in with that. I know not all heli's have APU's, but it seems most twin engines ones do. I door gunned on blackhawks, and we had APU on those.... and the Apaches had APU's as well. Anyhoo, the end state in my mind was to flip an aux switch (that's linked to sound 2) and have APU and lights come on, then other aux would be linked to sound 1 (which would be turbine spool up to idle).

[sfcfury]

Tracking now! That guy you listed seems like it would do the trick... in fact that seems like it would be useful to have for some other applications...

[F106DeltaDart]

Just found this and put in an order. Hopefully it will do the job: https://smile.amazon.com/gp/product/...TP8E47U9&psc=1

[F106DeltaDart]

Can you do away with the motor board? And just go direct to the receiver? Then is just be an on/off switch on the transmitter for that channel? Or is the motorboard needed to make it spin period?

Without the motor board, the gun would just spin endlessly. The receiver always sends power down the servo wires. It would need some kind of switch activated by the signal wire to turn power on/off. The only one out there that I know of is this, and its been out of stock for over 6 months now: https://hobbyking.com/en_us/turnigy-...-switch-1.html

[sfcfury]

Following all of the discussion on the mechanics closely. Hoping to get mine to fly on the test rig soon. I am continuing work on the gun turret at the moment, and finished up adding the servo for gun elevation. Used a 5 gram servo that barely fit inside the housing and some old 450 ball links to get it working. The movement range actually mirrors the real thing pretty closely. I also cut open the bottom of the turret, as the real is open as well for maintenance and ejecting casings. I’m still debating whether to add the cover plate on the turret or not around the barrel. In the States, it is kept on, but it is usually removed in combat environments for accessibility to the gun.

One other thing I’m still trying to figure out is a mechanism to trigger the gun barrel rotation. As of now with the retract motor board, the barrel spins for 4 seconds when triggered. Does anyone know of a receiver activated switch that I could use to trigger it? Would be nice to be able to fire it for different intervals other than 4 secs.

Can you do away with the motor board? And just go direct to the receiver? Then is just be an on/off switch on the transmitter for that channel? Or is the motorboard needed to make it spin period?