Sethhunter

Hi Guys!
A few recent pictures. This is the first time I've used Alumilite's casting resin and silicon molding compound. Boy it works nice. I used it to make a few instrument bezels. The Tach is made by mounting a bezel on the front of the instrument panel, a plexiglass lens behind it, another bezel in back for spacing (to create an air gap). The graphic is a reconstruction of the Morell Phylax tach on http://www.memaerobilia.com/instrumentselection.asp. Shadowing under the needle is part of the graphic. It looks better than my attempts at making the needle separate. I think the doors on each side of the tach provide to access the machine gun mounts for aligning them. I think some planes left these open - some didn't have a panel at all. I've turned the beast over to begin surgery to fit the DA50. While upsidedown, I included a pic of the tailskid (Alan - I know; it still needs some dirt spray on the underside!). Now the hacking begins!!

arspievack

Seth
Slow down on the cockpit till you get the stuff I sent in the mail. Sent it Friday. Let me know when you get it.
Plane looks great
alan

Erich_Prinz

Seth,

What was the advantage of creating the original, then the mold, and then the final product for the bezel?

Thanks for the tip on the Alumilite too -- they have a nice section on making climbing wall hand holds - another project in the wings for me!!

How's the surgery coming along for the engine mount?

Erich

Sethhunter

Hi Erich,
Good question! Certainly the advantage is lost if you only need one piece. In my case I used three. My bezel has the flange flush to one side of the tube, not the middle. This enabled a simple one-sided mold with no undercuts. I put one (silver) bezel on the front of the panel, covering the edge of the plexiglas set into the panel. The second is behind the plexiglass (behind the panel), creating an airgap to the dial - you can see it in the photo as the grey surface inside the instrument. Of course a simple tube/cylinder could be used for that, but since the bezel's only take minutes to cast and perfectly matches the inside diameter of the outside bezel, why not? The third bezel will be used for the compass next to the seat. I wouldn't staunchly defend this method as the best way to go, but I did learn a bit about the casting, had lots of fun doing it, like the result and can see all kinds of applications!

PS - the surgery for the engine is underway. A bit scary. Prognosis is good. Unfortunately some of the cylinder and muffler will project below. The little service hatches will be useful for hiding the fuel dot, ignition cut-off LED's, etc. I'll post some pictures when I'm sure of the outcome!

PS - Alan - timing is good. I've put off doing more cockpit details until after the mechanicals (engine and radio) are done.

Erich_Prinz

Seth,

That makes good sense to me!

And yes, it's a bit disappointing to know the exhaust will not be scale, it's worth the cost when it's up in the air!

Erich

Erich_Prinz

.
*SLIGHTLY* off topic - but certainly smack dab in the middle of scale work.

Have a look over this guys work (Rojas Bazan) I hope you are all as impressed by this as I.

http://www.rojasbazan.com/video.htm

Erich

arspievack

Eric,
There is scale modeling and then there is maddness.
What a display!!!!!!
Thanks
alan

Sethhunter

Beautiful work indeed. It would be interesting to watch him work.

abufletcher

I some ways I'm glad that WWI modeling doesn't allow us to decend quite this deeply into madness! Seth's work is already enough to blow my mind!

I can hardly wait to so all of Seth's Pfalz all together in one place!

Erich_Prinz

Hey All,

This certainly isn't to take away from Seth's work here. Clearly a spinning prop adds some drama to the maddening detail, but those ships will NEVER fly. I did know everyone would appreciate those efforts, but a flying scale ship is always tops in my book!

Erich

Erich_Prinz

Seth!!!

Hey, we need an update on the project!!! I was expecting to see video of the maiden voyage by now.

Any progress?

Erich

Sethhunter

Hi Erich - Yes I know I'm way behind in posting. The truth is, the engine (ignition/fuel/etc.) has been quite a challenge. I know some folks will be disappointed in the exposed powerplant and muffler - so I wanted to get closer to finished before posting the steps along the way! I hope within a week to have the nose repainted and the plane right-side-up again. I'm still leaning towards making a composite (carbon/glass) spinner, and hope in a few days to order a mini lathe to cut a wax mold. I've also been dragging my feet regarding reciever choice. I'd like to consider a Futaba spread spectrum module for my 9C but I'm not sure they're in production yet?? Another option is the FASST 6 ch or a plain-old 72 mhz PCM. BTW I received Fritz in the mail from ThePilotPeople. They make a nice pilot. ANyway, I hoping to fly it in July and start a quick build Junkers DII. I promise more pictures in a few days. Thanks for checking up!!!

arspievack

Seth,
We're all here waiting. Press on, but no compromises.
alan

Erich_Prinz

Seth,

Sounds like reconstructive surgery!

With all the cool choices in radio gear, it can be difficult to choose. Just remember what we had available in the 70's and 80's worked. The choices today are more about feature set and far less about model 'rekitting'.

Please document what you've done with before and after with photos. It's a great learning tool to see the great techniques you've deployed to build. And any reason to buy more tools like a lathe is a good reason!

Thanks for sharing. Even though I'm anxious, I agree with Alan - take your time and make it right.

Erich

arspievack

And since you're at the radio choice stage, how about including a gyro for at least the first few flights? Pitch is usually okay and controllable if you've got the CG right, but roll can somethimes be a ***** if there's a hinden warp somewhere. (Probabaly not possible with your building skills, but I got killed by this once on a very humid day).
And finally please ignore all the advice you'r getting , we're all just jealous of the beautiful job you've done.
Regards
alan

tommyp

My Feedback: (1)

Hello Guys,
I saw this and thought it might be of interest here:

http://www.aeroforum.org/

Go to "BUILDERS"

Go to "FTS Projects"

Click on "FTS Pfalz D.III project"

You might also be interested in knowing (in case you haven't already heard) that the current issue of WWI Aero (#196, May 2007) includes a compilation of Pfalz models, including plastic, Free Flight and R/C version. You'll see a picture of Alan from 1971, Seth and beautiful Pfalz assembled in his yard, and Kurt Bengston's design from Aerodrome RC. There's also mention of this thread, so hopefully it has helped to bring some traffic here.

Best regards,
Tom Polapink

arspievack

Tom,
Thanks good lead. I'm signing in to Aeroplane site
alan

Sethhunter

Hi everyone!
Tom - beautiful magazine and great column as always. Very nice to see all those Pfalz models. I hope Dan's will be flying again soon. His interference problem (at last report anyway) was prompting me to think more seriously about spread spectrum. BTW - I'm also enjoying Skyways immensely. I wonder if anyone has built a model of the Gee Bee Time Flies - that's a slick looking airplane. Alan - thanks for the gyro suggestion. I wouldn't have thought of that. I usually put in some expo to have the extra throw on demand, but the gyro idea is intriguing! I hope you got my email about the docs you sent. Thanks again - the details will be useful when I flip the "crate" over and get back to work on the "office"!!

Here are a few pictures of recent progress and unfortunately Alan, lots of compromises!

I don't recommend installing a firewall after the fuselage is built, but here's how I managed. I first checked that my nose ring was plumb using chaulk lines. Then bolted a plate to it, and the engine to the plate. I mounted a plate on the engine standoffs and used it to mark the fuselage, and put marking lines on the plate so I could reproduce a template that matches the fuselage interior. The pictures show bits of the process. Since I couldn't fit a firewall into the plane in one piece, I laminated it up using three layers (two 3/16 and one 1/4 ply), each layer in two halves, with the split alternating vertical and horizontal. Then put in some heafty ribs to tie it into the landing gear sub-bulkhead, and stringers, and increase bending stiffness. Also tabbed the structure into the fuselage shell with fiberglass. (The photos show the marking plate glued into a a plywood sheet to mark out the shape of the firewall. This is just to get a flush surface to transfer the points - I wouldn't use a glued-in piece like this in the final firewall!!) The final engine opening, while big, is cropped closer to the cylinder than some of these pictures suggest.

Since the rear carb pushed the fuel tank back slightly into the radio compartment, I made a light-ply tray to carry the tank so any leaks would drain forward of the radio compartment (also put weep holes in the bottom of the fuse to prevent pooling of fuel). The tank-tray has a top on it that I strapped the receiver battery to. The tray bolts to the firewall in front, and the radio bulkhead in back. The ignition module and battery will be below the tank. Hopefully the batteries are separated enough to prevent noise pickup. The carb extends into the plane of the firewall, so I built a well around it again to keep fuel out of the airplane.

I made engine standoffs out of PVC, and mounted to it a bellcrank for the choke linkage. The link is manual, and extends out the bottom next to the inverted pitts muffler. The standoffs also hold the inside ends of brass tubes that guide a screwdriver to the needle valves deep in the airplane.


I ordered a 7x12 mini-lathe and carbon fiber so I can start on the spinner. TOOLS!!

arspievack

Seth,
I did get your note and glad to hear you think the info will help. I'm enjoying your work (struggles) installing your engine and tank. When I scratched models I always built around the engine I planned to use and drew the instillation into the fuselage build drawings to avoid the stuff you're describing. (An after the fact instillation)
Doing so gave me a maximum chance to hide the engine as completely as possible and then having made that decision had to be very careful about weight so I didn't end up with a plane weight that was too much for the engine.
The down side is that method frequently became a problem in how to get air flow to cool the engine

How about a two cylinder in-line engine? I'm just trying to sprend more of your money. Good photos , thanks
alan

Sethhunter

Hi Alan - yes that definitely would have been the smart way to go. I'm not sure a twin would fit this airplane any better. If I were to start over, the most affordable approach would probably have been the RCV 120, and about 10 lbs lighter. The weight really drove the engine decision and the fuselage construction drove the weight, as you alluded to many pages back. I could have done more to compensate. At the end of the day, I decided to end "the obsession" on this airplane since it will only fly at the local field anyway, and the DA50 is a nice size engine to have for sport flying (it may end up in an ARF Extra or some such airplane). Another choice would have been the OS straight 6 that one of you guys posted a few pages back - but $3k was definitely out of my budget!!

arspievack

Seth,
The news that your plane is destined only for fun flying at the field has made me call my psychiatrist for an emergency visit. This airplane is good enough for "Top Gun" and similar
contests. We need to find you some sponsors, who can pay for:
1) A scale 6 cylinder MB engine
2) A trailer to carry this thing
3) Contest and travel support money
4) Publicity agent
Modeling as you know has become big business. Only artists like yourself can carry the flag into battle.
Maybe we need to raise money on a Pfalz web site.
ars

Erich_Prinz

I have no experience in the scale side of things (Top Gun), but I've seen the work accomplished by those craftsman and I couldn't agree more with Alan on this.

Erich

FokkerAce

DITTO's

This is a unique model!

FA

Sethhunter

Thanks Tom for the link. I'm in the middle of reading Herr Engels great Fokker-Team article in WWI Aero. I can't imagine building 16 full scale replica's at once! I have a hard enough time building one or two models at a time. It's especially exciting (for this thread) to see 2 Pfalz DIII's on the list.

Hey the sponsorship idea is stunning! Never would have thought of that. I appreciate you guys thinking big but I don't think I can take the pressure!!

While the paint is drying on my fuse I thought I'd post a pic of the pilot, and where I'm going with the aileron cable connection.

The biggest challenge with the aileraon connection is the relatively small space for the connection hardware, that has to travel back and forth between two ribs. I don't want to risk it hanging up on a rib, so the length of the connector has to be pretty short.

The kevlar thread looks like it will work much better than cable, and it seems to take paint well enough to tone down the yellow color. The picture shows the centersection where the aileron servo drives a U-control bellcrank, that moves 4 "pull-rods" that exit into the lower wings. After trying various arrangements, I settled on "sideways-corkscrew" ends on the pullrods. The kevlar cables have loops on the end to twirl onto the corkscrews when the lower wing panels slide into place. Then the tension gets taken up by attaching the turnbuckles at the ailerons. Although control cable tension should keep them from unwinding, I'll probably add a zip tie through the corkscrew coils to keep the cables in place. The kevlar loops are made using a bowline knot, covered with heat shrink tube. A drop of CA keeps the kevlar fibers in the loop from fanning out.

Mode One

"Danged" if the guy don't look like Bruno Stachel! To bad you built the DIIIa and not the DIII. Oh, well, maybe the next one!