500 Size AH-64A Apache build

[n4893]

Looking to buy a 700 size RC helicopter, electric, Jet ranger, or eurocopter astar 350 email me at n4893@lapd.online thank you.

[JFandL]

Thanks guys, I think this one will be joining my regular rotation to the field now, it's a lot of fun to fly!

Very nice on the build and flying!!!!

John

[F106DeltaDart]

Very nice on the build and flying!!!!

John

Thanks JF! Been flying the Huey much?

[Prowler901]

Where do you get a 500 size heli mechanism/frame that could be used with some of these Roban kits?

[F106DeltaDart]

Where do you get a 500 size heli mechanism/frame that could be used with some of these Roban kits?

There are a few options for that. First, would be the RCgroups classifieds. Look for a Trex 500, preferably the ESP version. Double check whether the fuselage you are looking at has a belt or shaft driven tail and take that into consideration. I've usually been able to find an airframe with servos for around $300.

The other option is the Hobbyking HK-500 series. These are cheap kits, and will require a few replacement parts for reliability. The frame, head, and tail gearbox are actually very well made, but you should replace the mainshaft, all gears, and torque tube with Align spare parts. Be sure to use the lower tooth count Trex 500 (not pro) tail drive gear to get a higher tail RPM. This gets important, especially if you are looking at fitting a multiblade head.

[Prowler901]

Thanks, Delta! That helps a lot. :Cool: We are a long way away from that level of Helo. But, we hope to get there at some point.

[F106DeltaDart]

Thanks, Delta! That helps a lot. :Cool: We are a long way away from that level of Helo. But, we hope to get there at some point.

Glad to help! If you have any more questions feel free to ask away. The scale heli community is small but extremely rewarding! It always surprises me that they haven't caught on as much as fixed wing warbirds have.

[OV10]

It always surprises me that they haven't caught on as much as fixed wing warbirds have.

I'm not surprised DD........it takes a lot of dedicated practice to be an accomplished CP heli pilot.
And if you look at the general RC club population the majority are barely in the advanced skill levels for fixed wing.
I gave up and sold both my Blade 300 & 500 after almost 2 years of sim and real air time.
Just could never get past the being stupid phase of flying nose towards me.:(

[RCjetdude]

I forced myself to learn nose in hovering and the pilots promenade from both directions. That was back in 1990. Now I am just a little rusty. I can still do it but the lack of stick time on a heli shows. I always wanted a scale Apache back in the day before electrics but it was always out of my reach. Still is come to think of it. :Thinking:

[F106DeltaDart]

I'm not surprised DD........it takes a lot of dedicated practice to be an accomplished CP heli pilot.
And if you look at the general RC club population the majority are barely in the advanced skill levels for fixed wing.
I gave up and sold both my Blade 300 & 500 after almost 2 years of sim and real air time.
Just could never get past the being stupid phase of flying nose towards me.:(

I hope you guys both consider going back and trying some Helis a bit more in the future. The tech in modern FBL units is miles better than what it was even 3 years ago. Many modern units even provide a "panic button" or auto level type feature to ease the scare of an creating an expensive pile of parts. Some are even programmable by bluetooth, so you can adjust settings from your phone without fiddling about with plugging in cables at the computer.

As for my comment, I more meant within their respective user bases. Warbirds represent a pretty big chunk of fixed wing modelers. With Helis, scale seems to be MUCH more rare than 3D. And for that, I still can't fathom why..

[RCjetdude]

I always preferred scale to 3D. Perhaps sometime in the future I will get the opportunity to get one.

[JFandL]

Thanks JF! Been flying the Huey much?

Yes, she has no dust on her for sure. However, someone talked me out of her back in Oct. and I'm now building another UH1-B. Almost the same setup but this time I'm going to model a 205th Geronimo bird instead of the 116th.

[F106DeltaDart]

Yes, she has no dust on her for sure. However, someone talked me out of her back in Oct. and I'm now building another UH1-B. Almost the same setup but this time I'm going to model a 205th Geronimo bird instead of the 116th.

Awesome! Let me know if you need another fuselage. I've got a spare laying around that I'm not doing anything with. I've got a 500 size UH-1C fuselage on the way for my next project from a different company (PKM). I think the proportions are a bit more correct than the old Aerodyne fuse.

[JFandL]

Yes the tail is for sure a lot more scale! I already have the fuse. but thanks for the offer!

[F106DeltaDart]

Well, I took the Apache to the Texas Scale Championships on Saturday this weekend, and things could have gone better... First flight went awesome, the chopper performed perfectly and I completed all of the maneuvers without too much difficulty. The second flight however, did not go well. I was climbing into a wingover turn, and heard the dreading shredding noise of a main gear being torn apart. Power dropped almost immediately, unlike last time where I was level and at altitude, I was pointing downwind, with the nose aimed at the sky at about 50 ft. I was able to get the bird level, but couldn’t recover enough RPM for a successful autorotation. Keep in mind this is a 7.5 lb heli 500 size bird, so she drops like a brick without power. It hit level, and in the tall grass about a foot off of the side of the runway.

Damage was admittedly nearly not as bad as it could have been. Since pretty much all the rotor energy had been expended, the head and blades are undamaged. The worst is a few large rips in the fiberglass, and a broken gear strut. Otherwise, it was just the glued on detail pieces that came off. It will fly again, but the main gear really concerns me. There was no clear point of failure like last time. Pinion was still aligned properly, one way was tight, and it performed the exact same maneuver before without issue. I’m starting to think that looking into a custom CNC gear might be a better way to go. Or, just sticking to level flight and low torque maneuvers.

[Hardway]

FUN FUN Helicopters!!! Sorry. A real bummer for sure... Sometimes they have mysterious things happen for no apparent reason... Usually after you have spent a good year tuning them to perfection with zero glitches.... Then they break!!! :P

[F106DeltaDart]

Finally getting back to this project after a few months. The new landing gear and main gear are hopefully finally on the way here.

In the mean time, I wanted to try to tackle some of my issues with intermittent tail rotor authority. The first item on the list was reversing the direction of tail rotor rotation. For the most efficiency, your forward-most tail rotor blade should be rotating up into the rotor wash. The opposite was true on my model due to my angle gearbox. So, I decided to switch up some of the internal gearing, by moving the bevel gear that turns the drive shaft from the top to the bottom side. This involved very carefully pressing off the stock gear, and securing it on the other side with some JB weld and a pin. It’s nice and solid now, and the tail rotor direction is correct!

This is only part 1 of the fixes. I also have a few pieces on the tail rotor itself that I want to change that I’ll get to next..

[F106DeltaDart]

Finally got around to working on the rest of the tail rotor. I had 2 main issues with the CNC helicopter tail rotor I’ve been using. Problem #1 was vibration. The “barrel” that slipped over the tail shaft was not machined 100% correctly. When rotating that rotor by hand, there was a slight, but noticeable wobble at the end of the barrel. Problem #2 was a lack of full throws. The tail rotor only went to +/- 25 deg pitch or so. Most tail rotors can go +/-45 deg, and this definitely contributed to my tail authority issues.

The solution was to start from scratch, and build my own “cascade” type tail out of 2 stock Trex 500 tail rotors I pressed the bevel gear off of the stock tail rotor shaft, and pressed it on to a longer 4mm shaft. I also will be drilling a pin through the gear to pin it to the shaft. The two tail rotors are linked together with Trex 450 ball links. The result is balanced tail rotor with +/- 45 deg of pitch. And, it uses stock Trex parts, so it will be easier to repair if anything happens. One step closer to getting back in the air!

[F106DeltaDart]

After a lot of back and forth, I finally found a place willing to make me a gear in aluminum. This should be able to hold up to the stresses of a 4 blade head much better than the stock nylon (of which I have stripped 3 gears so far). It is a two phase operation. First, the gear has to be machined without the teeth on a machining center. It will come out of that machining looking something like this:

Then, I take the gear to a gear specialist that will cut in the teeth. Hopefully, the Apache will be flying again soon with a new aluminum main gear installed.

[F106DeltaDart]

Finally received my Aluminum gear this morning, and I can’t wait to start getting the Apache back together. The gear came out great!