Well done!

I like.

That's phenomenal!!

Great job!

Thanks for sharing!

Neal

You've done it again

Geoff,

You just keep raising the bar.  That is an outstanding project and very inspiring.  Tell us more about when it "...flew off my workbench..."   

Are there plans to have it move through the air?

Dave

One slight problem

Great animation, and I especially like the navigation and anti-collision lights.  Is there one on the belly of the aircraft too?  Then there is the white position light at the back as well........

The turbine start was perhaps a tad quick for the venerable UH-1H,  but I could hear the igniters, the clicking noise (equivalent of a spark plug in a petrol engine) hard at work.  You only switch on the landing light after the generators are on line because of the power drain on the battery, but a great feature.  The problem is animating a tail rotor, getting a motor small enough would be hard, but I have a solution!

Animate a helicopter which uses NOTAR technology, like the MD902 Explorer

(sorry for the blowing snow!) which has no tail rotor - but there are two engines, so you have twice the fun with the sounds for the engine start!

A really superb animation, thank you for sharing.

Norman

Nice

I'd have really been impressed if it had taken off. 

Nice work with the drive system. As always I'm impressed and get much inspiration from your projects. 

Are we going to see a how to article on this one?

Bernd

@Dave re: Airborne

Hi Dave,

Thanks for the kind comments.

Originally, I had not even considered it, but after seeing the Miniature Wonderland (Germany) airport video, I am sorely tempted !

Best regards,

Geoff

@Norman

Hi Norman,

Thanks for the kind words.

There is often a second light on the belly further back between the skids. Both spots can be lowered into place and turned on. I modeled the forward landing light deployed down. The tail white light was not on all the models I found pictures of. There was also a rearward red tail lght (optionally too) both of which I didn't model. Also there were various HF, VHF, and radar altimeter antennas that could have been added too.

Ah !! But remember we run with a 3-6X fast clock in HO operations!!    !! (Big Grin!!)

I had not even considered the NOTAR helo, but that would be an interesting idea! Strangely enough, it was my dear wife who challenged me to get the tail rotor operational too (left completely off the model at that stage in the video). Even if I didn't sync it to the rotor rotation, it is a huge challenge, but I have filed it away in the "I wonder if it can be done?" pile.

'Really glad a real pilot appreciates the effort!

Have Fun!

Best regards,

Geoff Bunza

@Bernd re: Helo Build Article

Hi Bernd,

Thanks for the kind words!

It can easily be done, but I wonder if Model RR's and editors are interested in animated helo's and planes? What do you think? Maybe if I add how to make it hover and turn?  (Big Grin)

Have Fun!

Best regards,

Geoff

A few thoughts

Great job Geoff!

I had a couple of ideas while watching your video. I noticed the motor armature is almost parallel to the tail boom. How about using a double output motor and running a piano wire shaft back to the tail rotor? Bevel gears from an old dental drill?

As for a flying model, I have seen some quite small flying models. Maybe not true HO scale, but close. Could you start with one of those and add the lights and sound? You would probably have to give up the cockpit detail to make space for the needed components, but I don't believe the extra parts would add enough weight to affect performance drastically. If you just HAD to have a true replica of a Bell, would it be possible to use the styrene body to vacuum form a light weight lexan shell, and then install the flight gear from a flying model? That would be way cool!

Ed

Blessed

Is the modeler who can run abreast Geoff Bunza! 

Work as I might, you keep moving the bar!  I have a perfect place for a Whirlybird now to keep my eye open for an HO kit of one.  Mine will rest atop a building!

Inspiration.com is what i'd call your website, Geoff.

Watching your video, I think I'll make my model showing a mechanic working at an open panel to simulate maintenance and avoid the inevitable awful 'does it fly' question.

Geoff, thank you once again for your willingness to share not only the concepts but the delightful details.

Joe Baldwin

Tail Rotor

All,

First, thanks to all for the kind words-- they are great encouragement to try even harder!

Rotating the tail rotor is a nightmare at 1/87 scale. First, it is possible to mount a drive shaft to the rear, but it would need 2 sets of gears to change directions of rotation to move the tail rotor. I suppose watch gears might be small enough, but the precision required for the whole assembly is a bit daunting to me. The other drive I have used before is flexible 0.5mm "stretchy cord" used for beading, but again two more twists in the drive path may be problematic.

There is also the somewhat non-obvious problem that the tail is actually NOT hollow, but solid plastic. So any drive path would have to be milled out along the way.

I don't know of a 1/87th scale RC Helo model, as Ed suggested, but it is a thought. I really wouldn't want it to literally fly around the layout, but a simulated hover might be really interesting. Dave had talked to me about simulated flight animation at the NMRA convention, and I still can;'t get the impressive vision of the Miniature Wonderland (Germany) airport video out of my mind...  I just can't drop the idea quite yet.

I had forgotten to point out that the model started as an old Roco 1/87 scale UH-1 helicopter... a nice model by itself.

Have fun! 

Best Regards,

Geoff

Air power?

Maybe you could spin the tail rotor with a jet of air. Assuming you could build a small blower, you could run a pipe through the tail and out the side with the opening toward the rotor. With the proper pitch, the prop should spin nicely. An alternate approach would use a tiny turbine in the tail, directly connected to the rotor.

pqe

A rotating tail rotor (TR) is...

Difficult in any scale, because of the 90 degree change in direction of the power train and the space needed for a TR gearbox in a 1:87 model.  Have you thought about a micro motor?

I have an R/C flying model of a Hughes 300C.

The US Military called this a TH-55 and it was the learner helicopter for many military aviators.  My model is approximately 1:72 scale, apart from the blades, which are way, way over scale, but it flies!

What is interesting is that the tail rotor motor is just 15 mm in depth (not including the spindle) and 4 mm wide.

The model came from Carrefour, a European Supermarket chain, so I guess Wallmart will have something like this.  Like everything, it is made in China.

The UH-1H fuselage length is 12.65 metres, the 300C is 9.4 metres

The question of scale has been debated quite a lot on other forums, like this from Model Railroader 1:72 scale military aircraft on HO layout  

There are a lot more models of both civilian and military aircraft in the 1:32, 1:72 and 1:100 scales, than there are at 1:87.

For a modern image layout Schuco have an 1:87 NH90  which is used by Coastguard and SAR forces in North America.  Revell have a number of helicopters at 1:100 scale but the only 1:87 UH-1, which I suspect your model is, came from Roco and is no longer made, but comes up on eBay.

The Minatur Wunderland in Hamburg is well worth a visit - or a visit via YouTube.  There are animated helicopters there, but when I last visited, a few years ago, they were in the air, but not actually "flying".

Derivatives of the UH1 are still flying, mainly for logging and fire suppression, so if you can find a model, it can be put anywhere on a timeline from 1957 to today.

I do like the suggestion about having an open panel with an engineer peering in, Maglite in hand (another LED) while the pilots do a ground run.  That is a very good reason for having the engines start and stop often too.

NW

Tail Rotor Drive Thoughts

Geoff,

At the risk of further straying from railroading, but touching on a common drive line issue for models, a couple of thoughts on tailrotor drive for your Huey model.

First, the tail rotor should be driven at a speed that is roughly the ratio of the main rotor radius to the tail rotor radius.  The tip speeds are almost the same.  For a UH-1, that works out to slightly more than 5 to 1.  

Second, You might consider an idea from the old Athearn "Hi-F" drive of the 1950's--use a folded belt drive.  This can solve both the 90 degree direction change (just as Athearn did from a longitudinal drive shaft to the lateral axels) and the modest height difference between the tail rotor drive shaft atop the tail boom and the vertical fin top mounting of the tail rotor.  You might even use it as Athearn did to proivide the gear ratio, though I suspect you will figure out how to do this back at the main "transmission."

I look forward to your further efforts,

Bill Decker

former rotorcraft research engineer--now a nearby (McMinnville, OR) neighbor

HO's other scale

I found a whilybird Bell 47 in 1/72 scale $15 off ebay.   Due here the 15th.

I'm thinking the rotor motor gets mounted under the copter in a 'base' to preserve the interior detail.

Joe Baldwin 

Rotors, Drives, and Comments

Hi All,

First, thanks for all the ideas and comments! The tail rotor drive is an entirely appropriate discussion, as it is a problem not only for this model, but many other model animations as well.

The air pressure drive is a good idea for very lightweight single speed rotors, like a windmill, but not for this model: I would want to simulate the power up and power down sequence, moving through a range of speeds, with a delicacy I haven't seen with air pumps. Further, the pump and control would not be able to be contained in the model. A below ground pump and air line might make it up into the fuselage, but likely not into the tail to the rotor, which though small, is not exactly ultra-light.

I have a 4mm X 8mm DC motor (smaller than anything suggested), and it is WAY over scale for the tail assembly. A 2.8 X 5 mm motor might be too big but barely acceptable-- but I haven't found one that small. Remember, this is a scale animated model, and I have no intention of it flying under its own power.

The UH-1 is an old Roco 1/87 scale model. Roco also made a 1/87 MBB BO-105. a CH-53, a Eurocopter, a DC-3, and several German fighters. Arsenal also makes a 1/87 UH-72, a CH-53, and a CH-34 helicopter, plus several versions of a DC-3, and others. Majorette made a 1/87 toy model of a Noorduyn Norseman floatplane (now out of production), which I used as the basis for my animated float planes.

If I can't get a 1/87 scale model, my personal preference is to favor the slightly smaller scales such as 1/96, 1/100, and 1/104 since planes and runways take a lot of room in general and I opt for "selective compression." Side by side with 1/87 vehicles and figures, they usually look quite good, even though 1/72 scale is a very popular scale for aircraft, with a much larger selection.

If I pursue powering the tail rotor, the best alternatives seem to me to be flexible 0.5mm "stretchy cord" utilized in a "band drive" arrangement as has been suggested before (still largely problematic due to limited space and twists required), or continuing the search for an even smaller coreless vibrator motor, which I don't even know if it exists.... OR wait until one of you solves the problem!    (Very Big Grin!)

Have fun! 

Best Regards,

Geoff

Geoff - since the "chopper"

Geoff - since the "chopper" isn't flying - could the tail rotor be powered by a very small nozzle buried in the helipad - blowing a jet of air upwards into the tail rotor blades, thus not requiring a "mechanical" connection?

@Shortliner

Hi Shortliner,

It might be possible to direct an air stream up to the tail rotor from the ground, but it has some problems in my situation: control of the air stream to provide a slow start increasing speed, and a wind down, decreasing speed is problematic. Also, the stream would likely not allow for hovering the helo, which this discussion has provoked me to consider. I do think it could be made to work in certain instances. While small and nominally lightweight, the tail rotor still has enough mass that the air stream might need to be a bit stronger than I would like.

Thanks for the ideas. Have fun! 

Best Regards,

Geoff Bunza

Moved to SMA 15

admin delete please.

Well, if you want small...

This is my small helicopter. It's going to be the centerpiece of a working heliport on a module.

A T-Trak module.

A SINGLE T-Trak module.

In N Gauge, 1/160.

That's N Gauge Kato Unitrack double track pieces it's sitting on.

Yes, it flies. I'll see if I can't get some footage of it flying in the next couple of days.

I have a similarly sized quadrotor that will also be flown from the module.

Helicopter DCC Build Components

HI,

I have been asked to share the DCC components to this Huey animation. There are two main pieces: The Digitrax SDN144PS DCC decoder was reprogrammed with the .spj file in the DCC package for your download here: http://www.scalemodelanimation.com/Articles/Huey/DCC_Package.zip  using the Digitrax Soundloader, and the DCC generator code from my article:  SMA22 – Low Cost DCC Controller/Function Generator for Animation, Test Tracks, Absolute Stopping Blocks for Keep-Alive DCC Locos  https://forum.mrhmag.com/post/sma22-%E2%80%93-low-cost-dcc-controllerfunction-generator-for-animation-test-tracks-absolute-stopping-blocks-for-12202555  which will sequence the Huey through its startup, run, and shutdown as in the corresponding video:

Here are a few more photos from the original build:

Two beveled gears and a 6mm planetary gear motor turn the blade via DCC control.

Control panels were reduced photos, printed and cut to fit.

LED connections with 36 Gauge magnet wire.

and the finished Huey ready for take-off:

Enjoy your flight and have fun! 
Best regards,
Geoff Bunza