SMALLnet post456

Saw your comments re Aerodyne, and thought I'd send the latest information I have on Allen and Dan Heinrich.

As of my last contact with Allen, he's taken employment somewhere down the hill, and is apparently making money for a change. Dan has taken over what is left of Aerodyne, and he promptly answered an e-mail inquiry I sent to Allen.

Allen says he is still open for "limited" business after his new job work hours, and at times on weekends. I run across Allen and Dan at our flying field occasionally, with their always really neat free flights.

The last e-mail address I had was: < > and Dan replied to my query. So perhaps all is not lost, per se. Allen's home phone number is/was: (760) 949-6606.

...I also heard from Brian Sodt (Vancouver, Washington) that after some delay, last November he received plans that he'd ordered from Aerodyne a while earlier. [JW]

In building diesel-powered models, what paint(s) may be used that will not be affected by the diesel fuel?

I seem to recall that one of the selling points way back in the pre-epoxy days was that diesel fuel wouldn't affect nitrate dopes the way glow does. Is that true? What about other paints?

Lately I have used commercially-available epoxy paints, as well as automotive urethane, but that seems to be overkill. Any suggestions? I am painting a couple of F2C Team Race models and my latest attempt to spray some epoxy was mostly a bad decision. I was wondering if there was an alternative. I may just go buy a spray can of Krylon or something! Bill

...Bill, I haven't found ANY paint that would normally be used on a model airplane that's affected by diesel fuel.

Some guys have claimed that castor oil bothers dope finishes, given enough time to do that. That may be right: I've had several well-doped firewalls become oil-impregnated to the point of uselessness.

But rather than believing that little by little, castor oil works its way into and through the finish, I think it's much more likely that it slowly sneaks into the plywood via the various holes drilled in the firewall.

Epoxy seems to vary tremendously nowadays. A friend of mine who's a professional wooden boat builder told me a couple of years ago that they had to give up on epoxy because of severe inconsistency problems. Polyurethanes seem to be the finish of choice in that field now... [JW]

I would also like to say that after trying one of the free R/C simulators on line (FMS) my flying skills have actually improved with a day and night difference! It may not help a Vet pilot much, but for a newbie it will make your lefts and rights, ups and downs (elevator and rudder/aileron) inputs instinctive in about two days. Although this is quite different than flying at the field, it is a tool I suggest for all who have little or no flight skills.

I have reservations and arranged for time off work to see as many of you as I can at the Little Rock meet. I will have the 1937 .049-powered Powerhouse and maybe another old timer to fly, but I look forward to some great conversations and stories from days past. See you all soon! John A Kennedy < www.samnine.com >

Man, Is JW's essay on scale model color ever the truth. The poor scale flier is subject to the myths within the minds of the judges. I have a book "USAAF Markings and Camouflage, 1941-1947" by Robert and Victor Archer with all the orders for paint and marking as distributed in those years. There must have been a small army of "Behind-the-Lines" types staying secure by issuing paint/marking orders on an almost hourly basis. :-))

There are items about shades, types and such as ".... not less than 7/16 inch nor more than 1/2 inch..." Actually it's almost funny.

At the other end of the spectrum, I had a good friend that served a long time in England as a Fighter Squadron Crew Chief. He said that most "paint/marking orders" wound up on the Chief's chore list. All the directed precision actually resulted in finding some buckets of paint, mixing if needed from leftover colors to obtain a close color, then application with a broom somewhere within the realm of the orders. He said it was all to do over in a couple of weeks.

Between maximum war emergency boost, blown oil seals, high-temp. exhausts and weather, it only took a half dozen missions to make a pristine P-51 look totally worn out.

Another reason that I have no desire to fly competition scale: Puritan theory just has no place in a real world. In an early Top- Gun meet, another friend had his color-and-markings zeroed out because he did not have color chips for his B-17 replica of a CAF B-17. He did have a picture PLUS a signed letter from the Confederate Air Force that the model was painted from the same paint supply that the CAF's B-17 had been painted with. Go figger.

Joe said some of the smartest things I've heard in a long time about scale model aircraft color. I have often been left shaking my head when a modeler agonizes over getting the exact shade of some color for his scale model.

C'Mon. The "real" airplanes we model are not that exact. Sure, the paper pushers in the military issued specs and even created "standard color chips" as far back as the 30's and maybe even the 20's -- but in real life a Sergeant yelled an order at 2 privates and they dumped a couple of gallons of whatever blue and white they had on hand into a bucket; stirred it with a mop handle, and proceeded to paint the fuselage of a PT-19 "Army Blue".

During the war it was even worse in the field. Things often had to be done in extreme haste. The black and white invasion stripes on some of the D-Day airplanes looked like they were applied with a broom. Some probably were. A war had to be won ! Getting the mission accomplished was the priority, not making pretty airplanes or even adhering meticulously to specs.

Even after Army airplanes started to be delivered in natural metal instead of OD and Gray, some combat aircraft were camo'ed in the field at the behest of the field commanders, and they used whatever paint they could get their hands on. Some "plain aluminum" P-51's were painted with British dark green in the absence of sufficient stocks of U.S. olive drab, for instance.

But there is much more to the subject of color. Paint from the same container can look very different just from being applied over different surfaces, let alone over different colors. And no camera or color film responds to every lighting situation the same way a human eye does. In fact, different human eyes can also respond differently. Individuals vary in their color perception.

About 1965 a photography magazine had an article testing and evaluating 8 different 35mm color films. They mounted 8 identical 35mm cameras on a bar on a single tripod and loaded each with a different color film. (I think they had a mix of transparencies and print films.)

They took this apparatus to different places and shot "the same picture" in each location with all 8 films. Some of the scenes were in bright sunlight; some included blue sky; some were on a rainy day; some indoors with and without flash, and so on.

There were a dozen or more different subjects in the various lighting situations, each shot with all 8 films. You could readily see the VAST differences in the way the different films handled any one subject. Some films were much "warmer", emphasizing the red tones, others leaned more toward the blues.

For years after that, I used Ektachrome X because of the nice job it did on blue skies. Not only was no one film "right" for all situations: no film responds to ANY particular situation exactly the same way the human eye does.

And there was an odd effect that gets into the subject of visual perception: If you looked at any one picture and covered up the other ones for the same subject, by itself every photo looked "believable" or natural. But when you compared more than one of the same subject side by side, THEN certain ones would be much more convincing, while others looked to be way off.

So you cannot depend on any color photograph to "prove" the colors on your model are correct. (Unless you have access to the actual full-size subject and take pics of it with your model in the same frame, under the same lighting at the same angles, etc. -- and the colors on the model and the full size match in the picture.) Tom

...Tom wrote much more on the way that the eyes and brains of living creatures register color -- including the fact that ducks see not three, but FIVE "primary colors". This makes fascinating reading, but would take up all the rest of this Posting. Using "editor's prerogatives", I've condensed Tom's submission. [JW]

On an exceptionally warm day for May, I got to demonstrate the Kloud King to Bill White, who recalled seeing them fly in FF contests with Brown Jrs when he was a kid.

Mainly it was a day meant for sailplanes, and I got in a lot of airtime. I made some trim adjustment (mostly moving CG and tail trim around) and had three good flights with the KK totaling 70 plus minutes.

Soaring is the exciting thing for me, though, as it's the hunt for lift that is the name of the game really: the hunt and then the fight to keep the fish hooked.

I had no real problems in framing up the Kloud King fuselage and tail parts. I did the landing gear installation my way (aluminum bolted to a plywood belly plate). I strengthened the fuselage structure too.

As for the wing, the laser-cut tip pieces follow the plan, but the plan is dumb and so the tip pieces involve too many butt joints, and looks weak and warp-prone. I am using basswood spars all the way. I had to make other changes too, where the parts and plans didn't correspond.

Anyway, working from a faithful copy of original plans drawn by an adolescent kid in 1938 is not always a good idea. Some degree of structural re-engineering is called for if you want a straight and durable model.

This experience made me appreciate the re-engineering that Doc Mathews or JO'R does when they redraw old plans. The plan for one model I'm building (the Vagabond) has none of these problems. Canadian Harry Volk drew it for me. He converted the 1946 design from FF to R/C using practical structures. He enlarged it to 84" span (from the original 72") as I asked, and changed the airfoil to what I wanted, too.

Of course, the original plan by Bill Winter was good free flight practice of that era -- so my model isn't "authentic". But it IS practical, and it will still look like a Vagabond. Bill

IN REMEMBRANCE OF John E. Brodbeck, Sr. -- THE FATHER OF "1/2A"! (continued from SMALLnet Posting #455)

On a day when there was a beautiful blue sky, we took the Baby Zephyr down to our local playground. My oldest brother fired up the K&B INFANT .020 and launched the Zephyr. It looped, went right over the top, and came zooming down towards his feet! My brother, who was tall and lanky at the time, jumped off the ground like a goosed kangaroo!

The Baby Zephyr appeared to zoom right under his feet! It then did a second loop and once again my brother went "airborne" with the Baby Zephyr zooming right under his feet! We all know that three strikes and you're out!! Therefore, my brother decided not to stay in the same launching area any longer.

On the third loop he took off at a dead run away from the launching site, but the Baby Zephyr, like a buzzing angry bumblebee, was hot on his trail!

My other older brother, sister, and I watched with utter amazement and a little trepidation as the Baby Zephyr literally chased my oldest brother several yards across the playground. Now we little kids were convinced! We were believers!! Those religious folks were right after all! There definitely are demons in the world and they are here to plague us! The darn model obviously was possessed by one and dangerous. Yea, oldest brother, demons are even more dangerous than our syringe with the "hypo" that you confiscated!

Nevertheless, my oldest brother was determined! He then performed some kind of strange exorcism. He breathed his warm moist breath on the flying surfaces of the model, warping this and that with his dragon-like breath. He tweaked on this and that, and then man- handled the hapless little K&B INFANT .020, by muscling the engine up or down, and left or right.

Apparently this bizarre behavior worked to get rid of our demon, because the little Baby Zephyr quit chasing my brother across the playground.

However, my oldest brother still made several more short flights, with just a little fuel in the tank, followed by a couple more of those weird exorcisms. I guess he just wanted to make sure that darn demon would not repossess our model. He then finally fully filled the tank and launched our model. We three little kids stood and watched in awe as the Baby Zephyr climbed overhead in a tight circle, higher and higher, into the beautiful blue sky.

We wondered: Is it possible for it to go even higher? It went higher!! My oldest brother commented that it was climbing like a homesick angel. When the engine quit, the Baby Zephyr circled beautifully overhead like the hawks and eagles we little kids had watched with such fascination and wonder. As a six-year-old, I was so very excited and astonished with how high the model went and how well it glided after the engine quit running.

It flew like the full-scale airplanes that we kids had watched so many times flying overhead. It was a far cry from the "toy" airplanes that we previously had tried to make fly !

Like the old song lyric goes: Those were the days my friend. We thought they'd never end.... We are going to miss you, John. Thanks for all the pleasure and joy that you brought into the world for us SMALLsters. You will always be remembered by us as the true father of "1/2A".

Here in New Zealand we recently learned of a low-key postal event emanating from Britain involving the 1950`s Vic Smeed 36" span 'Tomboy' model. I'm not sure if this design is widely known in the USA, but down here just about every modeller upwards of 50 years old must have built at least one. I recall it was the first successful freeflight gas-powered model I ever built.

Apart from compulsory 2- or 3-channel radio assist, this postal event specifies close adherence to the original design, including use of a Mills .75cc diesel engine, either original or replica, and the covering is to have the appearance of the doped tissue original -- NO glossy plastic film covering is allowed.

Several of us have been motivated to build another Tomboy, and the framing for mine is almost completed.

It must be fifty years since I tissue covered a model and I recall it being a rather messy operation using sprayed water, brushed clear dope, and I seem to recall a substance called banana oil was involved somewhere. Whatever, our tissue covering then was only ever marginally successful -- it was certainly the least enjoyable process of any project.

I have ordered some 'Jap tissue' from the LHS for this model and am approaching this operation with some trepidation. Some say to apply the tissue wet, some say dry. Some suggest it is applied with 'Balsaloc' or similar -- others suggest pre-doping the panel perimeters and brushing thinners through the draped-on tissue.

...Alan, I suppose that I qualify as "a" tissue-covering expert. I've been using tissue to cover my rubber-powered models since 1935. By now I can get that "covered with a single piece of tissue" look on my small airplanes without noticeable strain.

However, I wouldn't highly recommend "Jap Tissue" for use on a diesel-powered R/C Tomboy. It's just not that durable.

The coverings of choice in the Good Old Days for "gas models" were silk or Silkspan. Silkspan was originally developed as a teabag material. It came in light-, medium-, and heavy-weight grades. That was the stuff we used for "wet covering" -- Jap Tissue has hardly any strength when wet.

Modern Silkspan acts differently from the original material. I've quit using it on my models, because something in it seems to turn dope extremely brittle in a couple of years or less.

The last model I covered with modern Silkspan was a control-liner. One day while starting the engine of that plane. I dropped the glow plug clip onto the wing -- and it plunged straight on through the top and bottom covering !

My preference now is for a synthetic model covering that looks and feels exactly like lightweight Silkspan. It's applied dry -- moisture has no effect whatever on it -- and heat-shrinks to attain tautness. It's sold under various "-span" names: Starspan, Litespan, Polyspan...

There are several ways to adhere coverings such as Jap Tissue, Silkspan, and Polyspan. I prefer to use dope: plain clear nitrate dope, NOT the low-shrink type or butyrate: PLAIN NITRATE CLEAR.

Apply three good wet coats to every part of the model structure that the covering will touch. Sand lightly after the first coat dries, to remove the fuzz.

Lay a smooth, slightly-oversize piece of covering over the part to be covered. With a brush loaded with either thinner or highly- thinned clear nitrate, apply the fluid down through the top surface of the covering, and press it into contact with the wood. Do this ONLY around the perimeter, NOT on the ribs or crosspieces.

(The reason for pre-doping ALL the wood that the covering will touch is so that when the finish coats of dope are applied, bare wood areas inside the perimeter won't soak up dope through the covering. When that happens, those areas look dull and lusterless. Then extra coats of dope are needed to eliminate those flaws...)

I don't use a razor blade much to trim tissue or Silkspan. Instead I trim the external edges with a small piece of 360-grit wet-or-dry abrasive paper. I sand "round the corner" with that, to provide a feather edge to the covering rather than a sharply-cut one. (That's why my models appear to be covered with a single piece of material: the feather edges blend together unnoticeably.)

Tissue and Silkspan can be made to conform around curved edges such as wingtips by forcing it down and around with wet dope and a water-wet fingertip. (Dope and water are quite compatible. Moist tissue softens, and can be formed over mild compound curves without a wrinkle or foldover. It takes a little practice, though -- like any useful skill.)

Polyspan is different. Its fibers are stiff. I adhere this material to the main structure with dope, as described above -- but to make it go around the trailing edges and wingtips etc., I use another adhesive. Dope won't do the job alone.

I brush a narrow strip of Balsarite or the like under the edge of the covering; let that dry; then with a hot "trim iron" I work the edge down and around the wood. The iron's heat softens the Polyspan at the same time it activates the adhesive.

The only drawback with Polyspan (and its clones) is that it comes only in white. And since this material is utterly waterproof, it can't be colored with fabric dyes such as "Rit" or "Tintex". If you want a color finish on Polyspan, you'll have to do that with dope.

As for that doped finish: Use plain nitrate for the first, "sealing" coat. After that, butyrate can, and should, be employed for the topcoats -- either clear or colored. In fact, I haven't seen any colored nitrate dope for decades. Butyrate has long replaced that in the USA, and probably everywhere else too. Butyrate is far more resistant to sunlight, accidental ignition, and fuels containing alcohol.

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SMALLnet Posting post456