Scale UH-1H 450 Class Custom Build Project

[MariaFan]

Highspeed,

No worries buddy. I knew I would hear from you sooner or later.

I am so excited for you!!!!! Your idea on the tail boom and everything else sounds like an excellent solution. And having that mill and lathe must be a dream come true.

I would like to see your latest files so I can wrap my head around what you're talking about on the undercutting issue.

Diamond cutters?? Excellent. Stepping into this big-time.
Watch out for the CF dust. If you can run a coolant of some type over the cutter, that would be the best solution. I think you mentioned you were running coolant??

As usual, I loved reading your latest report.
I can't wait for the maiden flight video.

[ahummingbird]

Looking good mate! Seems you have some good engineering logic going on there ending with some excellent solutions
I gotta say though, I am just a little jealous of your new toys .... OK i'm a LOT jealous.
Keep up the good work

[Highspeed1964]

So I've been putting the parts for my newly designed tail boom through the CAM software to generate the g-code files for cutting on the mill. In doing so, I came to the realization that I had an unnecessary part in there as the spar I will be using eliminates the need for the canted bulkhead.

Additionally, eliminating this bulkhead will allow me to use one part instead of two for the spar and gearbox mounting block. This change will accomplish two things:

1. Less parts.
2. Better structural strength.

If you look at the picture below, you can see what I am talking about. Firstly, the canted bulkhead pretty much duplicated the function of the spar - holding everything at 42 degrees on the leading edge of the vertical stabilizer. (Red arrow in the picture.) So that bulkhead is coming out. Secondly, the two metal parts at the yellow arrow (gear box mounting block and the spar) would have to be cut at a 42 degree angle. This adds "shearing" stress on the assembly rods as the two parts press against each other and tend to slide in opposite directions into the rods. So by combining these two parts into one (after removing the bulkhead that separates them) the forces of the assembly rod will not cause any stress on itself from these angled surfaces. The force will be longitudinal which will hold this newly designed spar/mounting block solidly in place against the outer bulkheads. An added benefit is that I will not have to cut the carbon fiber tubing at an angle either!



Finally, I'll be cutting some parts today if all goes well. I have been researching feeds and speeds for cutting carbon fiber plates and it has been a bit daunting. But I think I finally have a handle on it and I'll be doing some test cuts to fine tune the feed rates for the bit and material and get the best cut/finish on the final parts. After that - it's CUTTING TIME!

I'll be starting with the side plates for the mechanical assembly (I'll be cutting the metal parts such as the motor mount and bearing blocks for that next week) and then I'll cut the tail boom bulkheads. I'll be able to test the assembly without the metal spar/mounting block by replacing that part temporarily with some additional tubes until I can get that part cut out of metal. There are some challenges on that one from a milling perspective (MariaFan, as soon as I have that part redesigned I WILL get the drawings to you - I promise!) but I want to get a test assembly done so I can fine tune the design if needed. I'm also going to start with a carbon fiber bulkhead where the tail boom is mounted to the tail boom mount on the mechanical assembly for this test. It will be made out of aluminum in the end state, but I am waiting for the 2mm threading tap to arrive before I can finish that piece. (The devil is in the details in these projects!)

Anyway, off to the mill now. Going to have some fun today! (Yes, MariaFan, I'll be using the coolant system to keep the CF dust to a minimum.)

As always, thanks for following this build.

Highspeed

[Highspeed1964]

Hey folks, got some progress going on at the mill today! Woo hoo!

I made the first true prototype parts and these are carbon fiber components. I decided to make the side plates for the mechanical assembly "core" as mentioned in my last post. Well, I gotta tell you... they came out BEAUTIFUL! I got the feed rate set through the test pattern and came up with a good clean looking finish to the cuts so I proceeded with the actual parts and here are the first two.



The two main frame side plates for the "core" of the mechanical assembly. Looking so cool!!! They are laid out in the same orientation I cut them. This was done to minimize waste material.



A perfect match! (Yes there are two parts in this photo, stacked one on top of the other.)



Just to show you, I've spread them apart just a bit. These things are beyond words for me at this moment. I am stoked that I am finally making productive progress with my milling machine.

Oh and btw, each plate is 29 grams for those who may be wondering.

Anyway, after taking a few moments (ok probably more like an hour) to revel in these parts I'll be getting back on it for the tail boom bulkheads. Wish me well and I should have a prototype tail boom frame for you (sans vertical spar for the time being) by this time tomorrow.

Again, thanks for watching.



Highspeed

[MariaFan]

Dude,
Those parts look absolutely beautiful.
Masterpieces of CF and design and a good mill.
(of course, the guy writing the code did a good job too)

And just think... You can make more anytime you want to.

[Highspeed1964]

Hello again, my friends.

So I didn't get quite as far on the tail boom as I had hoped to today but I did make some good progress. I got all the bulkheads cut out of the fiberglass and the rods cut to length (actually I still have one short pair to finish but it'll be done soon enough. However, I didn't get the spacers cut out yet so the whole thing is just loosely fit together for the time being.

On the up side, I did get enough done to show some more pics today! Don't expect perfection yet since, as I mentioned already, I do not have the spacers installed. The the placement is an approximation at the moment. But enough yapping - on with the pics!



Initially, I started stacking the bulkheads as I removed them from the mill. I stacked them on a set of the threaded rods I will use for the final assembly. These rods have not been cut to length yet so it's a bit of a mess, but you get the idea.



A little closer view shows the nice carbon fiber pattern on some of the pieces.



Finally, I cut the rods to length and put them together in the appropriate segments. Here is everything fitted together (without spacers) so you get a feel for how this all goes together.

I'm feeling pretty good at this point to have some assembly happening on the final tail boom. Once I get the spacers cut and installed (I'll be using a temporary spacer where the vertical spar will eventually go for test fit purposes) I'll start working on the detail parts. The vertical spar will be one of those parts as well as the aluminum bulkhead at the base of the boom. (I'm using a carbon fiber bulkhead for the moment to test the assembly.)

Well, that's it for today. But I'm sure enjoying seeing some more progress on the actual model vs. design work on the computer. And of course, as always...

... thanks for watching.

Highspeed

[ahummingbird]

Well that's shaping up nicely

[MariaFan]

Originally Posted by ahummingbird

Well that's shaping up nicely

Agreed!!!

[Highspeed1964]

Hello again folks,

It took a bit to figure out the best way to cut the carbon fiber tubing for the spacers, but I got it. A vice, a "V" clamp, some painters tape (to prevent splitting/splintering) and a dremel tool with a cutting wheel. Once I got the process down, it took no time at all and I have my spacers.

Next I disassembled the tail boom as it was in my previous post and rebuilt it with the spacers and Voila! A good tightening of the nuts on the metal rods and the whole thing is good and solid. And strong! And has minimal torsion (twist) properties. Once I get it mounted with a metal bulkhead to the tail boom mount and install the actual torque tube assembly, gear box, etc. this should prove to be a solid tail for the Huey.

So without further ado, I present the latest pictures for your viewing pleasure!



Here's the completed prototype (minus metal parts such as the vertical stabilizer spar, horizontal stabilizer shaft bearing blocks, etc.) as I have it right now. The spacers are a tad short so the whole boom is about 5mm shorter than it should be, but I can adjust that with a handful of washers or I can just cut some new ones. (I planned ahead and ordered extra rods for just such occasion.)



Here you can see how it all fits together. There is a small amount of skew in the spacers so it might not look exactly straight but trust me it's looking quite good.



Looking down the inside of the boom, it is quite apparent that the boom is very straight indeed! And this looks very much like some pictures I've seen of the inside of an actual tail boom. Now, drum roll, please!



Here is the boom placed against the main body (as I have that right now) and man does it look awesome!

Well, as you can tell I've been having a lot of fun the last few days and it's paying off in results. I still have a long way to go but I can feel some accomplishment learning this new skill of working with carbon fiber. This project has challenged my very skills in every aspect and I have achieved/accomplished much to this point. Fiberglass, 3D printing, milling (both carbon fiber and metal - more to learn on that last one), design/engineering, fabrication, assembly, the list goes on.

Where are we at? Well I still have a lot of metal to machine in the CNC and on the lathe. Once I have that done, I need to finish the fiberglass skin components and fabricate the final run of the frame for the main body. Then assemble it all and build the rotor head and tail rotor assemblies. Finally, I'll be able to perform a test run-up without blades and make sure everything is working as expected. Lastly, I'll install the blades and do another test run-up and if all goes well - MAIDEN FLIGHT!

I'll probably be making the maiden flight without all the bells and whistles (i.e. doors, canopies, cowls, etc.) as I need to determine the best way to make and mount those components, but I'm getting anxious to see this thing fly. I know you folks have been patiently waiting that milestone and I'd really rather show you the completed model in flight, but that's going to be a while yet and as it is, the maiden without those pieces will be at least a couple months out or so.

Anyway, I'll be keeping you posted as progress is made so stay tuned boys and girls! And of course, as always...

... thanks for watching.

Highspeed

[MariaFan]

Most excellent!!!

Hey don't worry about the body parts for the maiden.
Danica and Maria never wear their canopies anyways.

[ahummingbird]

that looks fantastic!!
I eagerly await the next installment
This thread has become my highlight here on HF, and I'm just a bystander lol
Keep up the good work

[Highspeed1964]

So, taking a bit aside from the focus of this thread, but still somewhat on topic.

In my wanderings around the area I stopped in at the local airport to watch aircraft taking off and landing. Something I do on occasion. Well, this time I was parked in the same place I usually do and noticed something I had seen before but didn't think much about. Over the fence it appeared to be the roof of some odd sort of military ground troop transport (like an overgrown Hum-V or half-track or something of that nature). But this time something struck me as familiar. This I realized it was the roof line of my beloved Huey! I don't know why I hadn't come to this realization before but I went over and took a closer look over the fence and sure enough, it was an "H" model UH-1 just like the one I'm building in this blog.

I whipped out my cell phone and started taking some pictures as best as I could over the fence. I even went around the corner of the fence to get some different angles. Looking at the pictures and from what I could see first-hand, this appears to have been sitting quite a while. There is a thin layer of moss building on the exterior, the doors are not secured shut, the power train (engine, transmission, main mast) and rotor systems are missing and lots of stuff cluttered in the interior of the passenger space. However, the airframe itself looks straight and true and some of the flight control systems (cyclic/collective sticks and rudder pedals - possibly even the push-tubes, bell-cranks and mixing lever assembly) seem to still be in tact.

Of course my first thought was that it was sad to see this thing sitting there like this wasting away. Then I remembered a company not too far from here (about 100 miles away) that specializes in restoring UH-1H helicopters and either returning them to service for various organization such as police, fire-fighting operations and others, or making them into museum pieces. Last I had heard, they were always on the lookout for old airframes they could add to their inventory.

So now I'm on a mission! I'm going to try to track down the current owner or determine if it has been abandoned and see what can be done to put this in the hands of NW Helicopter who so passionately cares about bringing these aircraft back to a state of dignity which they so well deserve. So I'm going to start by contacting the airport management since the building this aircraft is sitting next to is vacant at the current time and see if I can't track down the owner. The markings are from the Washington National Guard and I'm sure they didn't just leave it sitting here although that is a possibility.

In any case, here are the pictures I got so far. I'm going to try to get some closer, more detailed shots when I visit the airport management.



When I first looked over the fence this is what I saw. From the parking lot I could only see the top 10 inches or so of the roof line and only about 4 feet back so it was not apparent what I was seeing at first. But the aerial cable cutter should have tipped me off.



Moving closer along the fence line, I could see into the cockpit area. The control sticks are still there as are the pilot seats and some of the instrumentation and electrical control panels.



All the glass (plexi-glass in actuality) is still there and most seem to be in good shape. There is signs of stress fracture (plexi-glass has a tendency to develop these over time when they have been "formed" to fit a curved surface) on some them but not bad.



It's hard to tell in this picture but there's definitely some intrumentation missing, however there's still a lot there that could make this useful.



I can't tell what it all is (perhaps some of the airframe components that have been removed) but there is a lot of stuff strewn about inside the passenger area of the cabin. You can also see the moss build-up on the exterior surfaces.



A complete looking airframe but there are definite signs of age as in these discolored and mismatched panels. Also, you can see that the internal power/drive train are missing as are the main mast and rotor system components.



Washington National Guard markings. The last digit of the serial number is missing on this side but the other side shows it as "0-15425". INTERESTING FACT: The WA NG was thoroughly engaged in the recovery efforts after the Mt. St. Helens eruption in the early 80s so it is possible that this aircraft served in that capacity.



Looking at it from the rear, you can see that the airframe still looks pretty straight and true. In addition to the engine, and other mechanical components in the main section, the tail rotor system is missing as well. However, the torque tube and 42 degree gear box are still there on the tail boom.



This shot confirms the final digit of the serial number. Also missing are the horizontal stabilizers.



It seems to have been used as a medivac unit in its' last years of service, further confirming it may have been used in the Mt. St. Helens post eruption recovery efforst.

So I'll keep you posted as to what I find out and especially if I can get it into the hands of someone capable of restoring it.

Sorry for the off-topic post, but I have developed a passion for these birds and don't want to see one just rotting away. So I thought I'd share what I'm up to when I'm not working on the project and perhaps some of you may have additional suggestion (i.e. tracking down ownership, other groups that might be able to restore it if NW Helicopters is not interested, etc.)

As always, thanks for watching and I hope this hasn't been too off-track for you folks.

Highspeed

[MariaFan]

That is so cool.
I wish you the best of luck in helping to get this Huey restored.

EDIT: By the way, it's your thread. You can talk about cats and dogs if you want to.

[ahummingbird]

Originally Posted by MariaFan

That is so cool.
I wish you the best of luck in helping to get this Huey restored.

Definately very cool

Originally Posted by MariaFan

EDIT: By the way, it's your thread. You can talk about cats and dogs if you want to.

Trains, lost treasure or even the mongolian mosquito, we will be here

[MariaFan]

A Highspeed bump.

How's it going buddy?

[Highspeed1964]

Hey MariaFan! It's been quite a while since I've been in here. I haven't been ignoring anyone (at least not intentionally) but life has many different directions it can go at times.

Nothing unpleasant in my case. It's just that focus has had to be diverted from the hobby for some time. And unfortunately, that does mean that not much has happened with this project lately either. I hope to get back at it soon. First things first, I need to organize my workshop (i.e. the second half of the garage) so that I can have a decent place to work on this again. Sometimes, though, stepping away for a bit can lead to clearer thought when picking it back up so maybe I'll make a bit quicker progress when I do get back into it.

Thanks for the bump. I've been missing you guys and also miss working on the project. Hope to be back at it soon.

Highspeed

[MariaFan]

Greetings Highspeed,

I'm glad to hear that things are good with you.
How is the real Huey working out?

[Tman49]

PING