Sethhunter

I'm sure there are ways to lighten and strengthen epoxy. I've never done a weight comparison on a particular part, but micro balloons in bulk sure are light. True, as you add more balloons, the mix becomes grainy, almost porous. I'm guessing this occurs at a mix of about 3:1, (microballoons to epoxy by volume) - which must be a lot lighter than straight resin. I've never tried this, but you might be able to thicken the epoxy just a tad and paint the inside of the mold, let it cure, then add a second layer of epoxy with chopped glass. I'm pretty sure this is how boats are built. You might even be able to add some color (maybe dope?) to the first layer. On the Mercedes DIII on my Phalz DXV, I didn't want to make each cylinder separately (because they're tapered). So I made a mold using some tips published in WWI Aero Magazine. I made a plug that I could split into 2 halves by gluing wood blocks together with spray adhesive and paper between them. Then turned the block "sandwich" to shape on a lathe (centerline in the plane of the paper). Then used a razer to cut the blocks apart by cutting the paper. Remove the remaining paper shreads and adhesive, and you have two perfectly matched halves. I then made a mold for each, sprayed the mold release into it and lay down epoxy and glass in each mold. When dry, popped-out figerglass "shells." The top of the mold left a nice sanding mark to trim the shells. Then just glue them together. Very light. I put a thin gel coat of expoxy on them afterwards, but you could try doing that in the mold first, as mentioned above. If you want to be even more clever, you can make a "core" for the mold that fits loosely in the cavity mold. Put the two together with locating pins, cast the part, and pop out a hollowed piece. I think the Aluminite manual describes that process (I will check).

PS - I just made up the prop strike scenario above. It didn't really happen and I agree it seems improbable. But our club, like many across the country, does seem to be having a lot of prop injuries. I only got nicked once - a little .15 glow in a tiny DH4 pusher got my knuckle while adjusting the needle. Must have been around 1970. Nothing like the injuries fellow modelers have been getting. Stay safe. Don't fly alone!

US185Damiani

Seth, and everyone else,


I'd love to see this beautiful bird at the Golden Age Air Museum RCmeetthe 1st weekend ofOctober

Lotsof good stuff happening!

take care

Mike
Damiani

Mein Duff

Thanks again Seth for sharing ! Some interesting fabrication ideas to ponder...you are right about boat building..my first job was at Boston Whaler (morning shift) spray painting gel coat on 22ft negaitve moulds. Then the fiberglass was layed up and both mould halves fitted together and latched until cured...so built from the outside in.
durable as hell.

Sethhunter

Thanks for the invitation Mike - see what I can do! Is your event at the Museum, in Bethel PA?

A few more pictures of progress on the engine... I decided to turn a brass plug and resin-cast the upper retainer plates for the valve springs. The springs themselves are wound from brass tubing. Some fun details on the cylinders include a compression relief valve and cooling system purge valve. I put a spark plug in the front cylinder. The others aren't visible. About all that's left is the intake and exhaust manifolds. then balance and out to the flying field. After the maiden, I'll put a bit of time into the radiator/cooling lines and fuel tank on the upper wing.

John Cole

My Feedback: (4)

"scribble-scribble-scribble...."

Seth, that's the sound of me taking notes on your great Argus replica, outstanding!!!

I am on a parallel path, perhaps a few months behind, in replicating a quarter scale Beardmore engine. The Alumalite stuff looks great, just got my supplies a few weeks ago. I hope mine turns out half as nice as yours.

Here's what a Beardmore looks like, and this is also the site where I found the Argus posters.

http://thevintageaviator.co.nz/proje...-engine-action

Take care, and thank you;

John

abufletcher

Both outstanding AND informative! Can't ask for more than that. I like the way that you have the the rocker valves set in different positions...adds that extra dimension of realism.

Nieuport nut

My Feedback: (10)

"A model within a model"

Very informative, Seth - thanks! Keep it coming.

Martin

JohnF

Seth, really cool stuff! So you will have it at the "Warbirds Over Jersey" meet?

Sethhunter

That's a GREAT video of the Beardmore running. A little tidbit some of you may have read in WWI Aero that surprised me.... If the prop came off the Mercedes engine (and I assume all the straight sixes of the era) rather than racing, the engine just stopped. Needed the momentum of the propeller to keep running.

John - I hoped to be flying it at Warbirds but alas life intervened! I was thinking of flying without the faux engine but I just hate the big hole it leaves so that cost me a couple weeks!! I haven't tried but I doubt I can fit all the parts in my Jeep Gand Cherokee (if it doesn't, that's another project that needs solving). Still, I was thinking I would bring the fuselage on Saturday for static display and bring the DXV on Sunday to fly. Should be a nice weekend. Hope the winds are mild. See you there?

JohnF

"alas life intervened!" I know exactly what you mean. Wish Ron and I could have had the Loening maidened but that didn't happen. I'll try to stop by the event however.

Sethhunter

Not much progress, except I did bring the fuselage out to our Warbirds event (yours truly CD) as a static display. Really raised a lot of interest! Can't tell you how many asked why I didn't motorize the valves on the Argus!! I can also confirm all the parts of this plane do not fit in a Jeep Grand Cherokee with the front passenger seat removed. The Halbi stands about 37" tall with the wings off, and the Jeep trunk height is closer to 34. So I layed the fuse down. I'm thinking there's a chance if I remove the back seat too, she might rotate to the vertical and then there would be room for the wings. We'll see in a week or so. (My family is wondering about the sanity of a man that piece by piece disassembles a perfectly good car.) This week I worked on the manifolds and must confess a blunder. The cowling I made is for a DII with the Mercedes, and the engine is of course an Argus. The difference is the Arugus exhaust is fully outside the cowl, whereas the DII exhaust snakes around closer to the engine. So some tweaks are in order. Working now on the big ole exhaust that runs back along the fuse. More pics to come. Here's the ones of the intake.

PS - also couldn't resist including a picture of the Pfalz DXV from our event. She's still flying fine. BTW - I got a lot of egging-on for bringing a fuse of the halbi with no wings from the 1/3 scale contingent. We had a some incredible displays of formation flying, with third scale AVRO 504's (two), a third scale DH4 (WOW) and a Moth! Super cool. The birds looked great. Thanks to all who participated. I hope the Halbi flies half as well....

JohnF

Hi Seth, sorry I didn't make it to the event, just too much going on around here. Glad to see your Pfalz still in one piece. I am trying to have the Vickers done by next summer. It will be pretty cool to see your Halbi and the Vickers in the air together.

Sethhunter

Well I've gotten back to this project and finished it up! Nothing left to do but fly. Maybe tomorrow. Here's a few pictures of the exhaust manifold going together, and some shots outside. I ended up needing 13 oz of ballast (the block & tackle in my garage was handy finding the balance point!). The weight is right on target at 42 lbs. The weight & balance spreadsheet was amazingly accurate. The fuji 64 is running great, but the Scimatar 22x10 seems too small - hits 10,500 wide open which I think is too fast. Anyone have a recommendation for this engine? You might notice I plugged up the hole in the cowl I was going to use to run the exhaust manifold out - Turns out the Halbi's with Mercedes engines ran the exhaust low. The Argus engines had the exhaust run over the top of the cowl - probably because the exhaust outlets on the head are angled upwards. whereas the Merc's are horizontal.

Sethhunter

And yes, it does "fit" in a Jeep Cherokee with 3 seats removed (though it looks kind of like it crashed there)!

udet1918

Congrats Seth a super job. All the best for the Maiden.

Ron

geezeraviation

My Feedback: (3)

Id go to a 24 10 if your tach radings are correct, thats a LOT of rpm. You're looking for 7000 to 7500. Your plane looks wonderful, cant wait to see the video of it in flight. Have a happy maiden

Happy landings Doc.

ARUP

Very Nice!!!

ZoomZoom-RCU

Hey! Did you know a Halberstadt crashed in the back of your car!!?? Beautiful work though.....flight videos?????? pleaaaaaaaase.

ZZ.

abufletcher

What a beauty! What a beast! All in one!

JohnF

Very cool Seth, good luck with the maiden.

Sethhunter

It flies!! Very nicely in fact. I got two flights in on Sunday. Video is posted at http://www.youtube.com/watch?v=U1_fQCKtrhQ
Next step - more scale details!

Thanks everyone.

abufletcher

Copious Kudos!!! Both the take-off and landing look smooth and graceful. Looks like you've got a winner here. Again.

udet1918

A Pfalz Triplane? Cruising for a bruising, but at 1/3 scale should fly nice. Congrats on the Halbie maiden Seth. The droopy trailing edge seems to work just like flaps. Great job!

Ron

geezeraviation

My Feedback: (3)

Another winner! Congrats Seth, and a hearty well done.
Doc

ARUP

That is very nice!!! Smooth flying, too!