SMALLnet post458

...Back again, fellows. The reason SMALLnet has been inactive lately is that my wife Joan finally lost her long struggle with cancer. She died at home a month ago, after almost all of our many children and other relatives visited to pay their last respects.

It's been a hectic period. Our home is small; and much of the time we had from 5 to 10 visitors here -- plus visiting nurses, hospice personnel, people from the neighborhood, and more...

Early tomorrow I'll be driving the 1000 miles from here in south- east Alabama to inter Joan's remains in the "family plot" in our old western Pennsylvania home town. But before I go, I wanted to send out a new SMALLnet Posting.

Incidentally, I wasn't able to attend the Randy Randolph Memorial SMALL meet at Dallas September 24. Few people did. The weather proved too threatening -- and that was during the Hurricane Katrina catastrophe. Though many of us dearly wanted in Randy's remembrance to make the trip to Dallas -- where SMALL model meets originated almost 20 years ago -- only a few fanatical fans (Alan Porter and Steve Adams among them) managed to do so.

Next year for sure ! [JW]

Sad to hear of the passing of another stalwart, Charlie Fries. It has been my experience of old age that survival comes at a cost of loss, and fear of further losses. In my case it has been an avocational double barrel--both the model plane and semi-pro Country & Western music scene.

One of my dearest friends, Armand Cote (prominently mentioned in several of my articles,) is currently making a difficult recovery from heart surgery, and I'm hanging on for him to make it. But with musicians booking to that big gig in the sky, I'm getting to be about the only really old-time pedal steel player in my area.

The kids that are coming along are pretty good, but most of them aren't into the Jerry Byrd C6 licks--and we lost Jerry this year, too.

Now we have a loss that affects all the Winnipesaukee Radio Controllers: We are losing our flying site at Laconia Airport. Where we have been operating is now a dozen feet deep in fill for extensive improvements and runway lengthening--there will be no place for us to operate.

We can use what little space is available for a very short time, but the security rules will require us to have orange flashers on our cars beyond the clicker gate--an expense most of us will not go to for a week or two more flying time. There is an interesting reason for this: Corporate jets that make extensive use of the field during the big races, are limited by runway length to less than full tankage. By lengthening the runway they'll be able to fill up--and jet fuel is the field's cash cow.

The Airport Authority tells us the relationship with the club has been exemplary, and thanks a bunch. We now have several members looking into alternatives. My best solution would be to win megabucks and buy one of the big farms in the area.

P-39's? Didn't we sell or give a lot of these to the Russians who loved that nose cannon for tank busting? I haven't a clue as to the Lend Lease color schemes, but seem to recall Russian pilots didn't gave a damn for paint as long as the guns worked.

I used to wonder about the usefulness of camouflage--it would seem harder to hold a gunsight on a shiny-glary aluminum target than a nicely darkened silhouette against the sky. Maybe the brass figured this out when they quit painting P-51s.

Really long winded this trip, but I cannot sign off without mentioning Charlie Bruce and the wonderful job he did restoring my ancient (and sentimentally valuable,) Elf Twin that had been sitting for years in pieces in a can of kero with stuck pistons.

Charlie's work included not just freeing the pistons, which every Elf fan knows cannot be pulled by the con rod because they are clipped in place and are push only -- but several broken and missing parts were brought up to snuff. Charlie did a great job and I want people to know it. Roy C.

I am a new member. I have read with sadness about the recent losses. My condolences, first of all. Those of us which are the best seem to go first. We must remember them and carry on.

I live in Melbourne, Australia. I have been working at many craft in my life and often reached good results. In the past nine years I have concentrated my efforts on ground-effect vessels and, as usual, I work with dynamic scale models. If they perform well, I then proceed to single and double-seater craft.

I own, among other model engines, a BigMig .074. I read one of the June 2000 SMALLnet Postings with Gary Edson's report about it. I tried to e-mail him but his address does not seem to exist. I'm now asking any of the members that have experience with this particular engine for a little advice.

I have run in the BigMig according to instructions. It is running well, especially after I added, as Gary suggested, a small ring of fuel line on the carburetor needle's tube to eliminate air leaks.

I am going to use the engine on a 28" wingspan ground-effect model, which has a wing area of 300 sq/in and a planview taper ratio of 2:1 (wing chord 14.5" at the root, 7.25" at the tip).

Several times I successfully tested the previous electric model I built, which is almost identical (engine: standard 540 RS, prop 7" x 3" APC, total weight 36 ounces). It flew very well in tethered flight (22' radius), taking off at 21 mph and reaching, in GE, at 2" from the surface, 43 mph WITHOUT ANY PHUGOID TENDENCY. (That made me happy!)

I changed the position of the power plant and the configuration from tractor to pusher: the model, once re-balanced, kept performing without any problem. The max. power used was 220 watts (11 V / 20 A at the motor's contacts) but probably much less because that stock cheap motor has a mediocre performance.

Taking off from the super-smooth surface of an indoor basketball court was easy.

My questions are: Will the BigMig .074 be able to adequately spin a 7" x 4" propeller ? Is the best fuel a 20% or a 25% nitro to achieve good results without wrecking the engine?

At present, I am running it on 20% nitro and I am obtaining a static thrust of 700 gr (24.5 ounces) at top rpm, using a 7" x 3" APC prop. The new model, a 3-channel R/C, will weigh roughly 33 ounces, but will have to take off from water. (I have optimized the "V" hull with double chines and three steps.)

I am just wondering if a 7" x 3" will give me sufficient airspeed to reach top speed in GE. I think it should be adequate to lift the model from the water.

...Bruno, there's a quick "rule of thumb" for calculating the approximate parameters involved in questions such as yours.

Take the rpm (in thousands) that your engine turns its prop; then multiply that by the prop pitch (in inches). The result is the MAXIMUM speed that combination can produce. Yes, that will most likely generate a SLOWER speed, depending on drag.

But it can never produce a HIGHER speed.

Your example given above, of a lift-off speed of 21 mph, shows that it's well within the capability of a Norvel .074. That should spin a 7-3 prop at least 18,000 rpm. And 18 times 3 = 54 mph -- the maximum possible speed a 7-3 at 18K could produce. [JW]

I enjoyed the latest Posting as always, and want to comment about the Tomboy. Bill White and I are flying them R/C with Speed 400 power ! There is a laser-cut partial kit available, drawn up as a 1/2A Texaco R/C, from B&W 1/2A Models LTD, 11206 Trentman Road, Fort Wayne, IN 46616. Phone is 260-639-6510, e-mail: < >. He has a list of plans and partial kits, mostly 1/2A Texaco.

Bill White flew his Speed 400-powered Tomboy and it so impressed me, I had to have one too. The only change I made in mine was to extend the wing one rib bay each side, hoping for better thermaling. Both models fly well, and all the B&W kits I have seen are of good quality.

I built a canard type glider out of two-inch blue Styrofoam insulation from a chunk of a 4 X 8 foot sheet. It had a two-foot wingspan. I flew it in a gymnasium. It had a glide path of 20 to 1, which amazed me.

Outside I threw it into the wind and to my surprise it flew a level path about five feet off the ground for about thirty feet. Then it slowed until it was at a near standstill, and dropped flat out of the air like a rock: no glide.

If anyone would like to experiment with my design, I will send it to you. Unfortunately, it has been in a store room for about twenty years and is now warped and broken. My children are grown that I made it for, and I am now 69. No one seem to want to hear about my foam canard -- so how about you guys ? I really think that if I had put the smallest battery-operated prop on it, it may have kept going until it hit a wall another twenty feet away.

Is anyone interested in the plans? I am an artist and have drawn my design many ways and in many configurations, but have forgotten about it for a long time -- until I read something on SMALLnet saying you had the urge to make balsa dust.

Please respond. Oh yes: I cut the whole thing out on a table saw to make such flying success so against the odds. All I was interested in at the time was a little quality time with my kids. Sadly, they never got interested and I just quit trying.

I'm new to SMALLnet and am looking for a Comet 54" Taylorcraft kit, or just the plans and copies of the printwood. Questions:

I'm pretty new to electrics. Been away from RC flying for quite a while. You guys have probably heard these questions several thousand times. But not being current, here goes anyway.

I'm an incurable designer/scratchbuilder, so my first project will be a 3-channel sport flyer. Flat-bottom parasol wing with 44" span and 320 squin area. Balsa construction. It's a blow-up of my Cox .020-powered "30's Sportster" design published years ago by Uncle Bill in Model Builder magazine.

I'm guestimating 24 oz flying weight with 10 - 12 oz wing loading. Fuselage volume in cockpit area is about 3" x 3". My questions: What servos for elevator and rudder? Geared or direct drive? Prop? Battery? Covering?

If it flies like I think it will (nice and slow), I'll do a construction article and send it to one of the mags. Suggestions on which ?

Does anyone have ideas on how to hold the muffler on the Norvel engines more securely ? Mine leaks pretty good around the exhaust port/ muffler fitting. I have had mine for several years, and I don't know whether Norvel has made improvements on the later engines. Also, I am considering removing the screen from the venturi. Is this a good or bad idea?

...Joe, I routinely remove the intake screens from ALL my model engines that come with those airflow-reducing gizmos. That's because they're located just where they do the most damage to the incoming inlet air. They slow it, and cause a pressure INCREASE in the fuel jet area. That's NOT a good thing. [JW]

I have just got my hands on a nice little Frog 50. But it is missing its piston, con-rod and needle valve assembly. It has number 1106 on the lug. Can anyone help me with plans or drawings of these missing bits, as I would love to get it running.

I am not sure which "Mark" it is, but it has the head with the two holes for removal.

I have two Allbon Darts, one without the needle and the other without the whole needle valve assembly and compression screw. Does anyone know where I can obtain such things?

I am interested in hearing from anyone that has had experience of Japanese-designed single-channel model aeroplanes from the 1950s and '60s....non-scale. I research and collect plans of these types. Regards, Peter ( Australia )

...Peter, Aeromodeller Annuals for the years you're interested in contain some small-scale plans for Japanese 1-channel R/C airplanes. [JW]

I guess I had a frustrating couple of years at the start of my R/C career in the mid 60's. At that time in England, single-channel was still the way in for the majority of modest-wage-earning F/F and C/L guys wanting to try radio, since multi-channel sets, whether reeds or the early proportionals, were way above the sights of the average bloke -- especially the imported jewelry-like Kraft and Orbit.

Push-button transmitters, super-regenerative receivers, and rubber- driven escapements were the order of the day around our club, and there was a definite 'mystique' about it. Some guys had a high success rate, whereas others (including me!) didn't seem to have the right touch.

I bought an ABC MiniSonic single-channel set, supposedly reputable stuff, good reviews in the magazines -- but I never had a flight with it. I put it in a Goldberg Junior Skylane, and on preflight range checks I could never get more than a twenty-yard maximum before the escapement either did its own thing, or nothing at all.

I figured maybe escapements were old hat, so I bought a relay receiver and a motorized servo, which went into a glider -- same problem. Around that time, David Boddington started a column called 'Button Man', dealing specifically with single-channel matters. One of his earliest reviews checked out a new 'pulse proportional' system by Webra, called the 'Picco', with a tiny magnetic actuator, which had rave ratings for .020 powered lightweight models.

So with renewed enthusiasm I persuaded the model shop who sold me the ABC gear to take it back in part exchange for a Picco set. It was very expensive, but Webra was a top German name, so the stuff must be worth it ? Wrong !

The range was even worse than the ABC set, so back to the factory it went; several times, in fact. Each time it returned with a letter saying there was nothing wrong with it, and why didn't I try new batteries ? Very annoying when I'd already spent another small fortune trying new ones each time before sending the set back.

I ended up taking it back to the shop guy, who admittedly was as fed up as I was with it, threw it in his dustbin and I never went back.

My flying buddy, John Reeson, thought we might have more success with boats, where range was not such an issue on the small lake available to us, and at least it would arrive somewhere at the lakeside eventually if there was a problem... We bought an O.S. 'Pixie' set, with a motorized servo which needed a separate battery supply. However, the extra weight was not a liability in a boat, and it worked -- every time!

Deep joy at last... Although we had a bunch of fun with the boat, herding the ducks around the pond, it still bugged me that the aircraft experience had gone so wrong; so when an article appeared in Radio Modeller with the circuit and board layout for the 'Cotswold' receiver, I sent for the kit from Harrogate Radio.

I built it with no problems, thanks to the excellent instructions, and tuned it up to the O.S. transmitter, with an O.S. compound escapement which had a bridle attached to the output giving 'push- pull' control instead of the torque rod used by the Elmic brand.

More success -- this was unheard of! The range was phenomenal. We never found out how far it would go, even with the receiver and escapement hidden in a dustbin to try and shield it. We never lost the signal before I lost sight of my helper waving his arms in response to the transmitter commands.

I was so encouraged by this that I then built a Transmitter -- the 'Simpletone', published in RCM & E about May '68. It was equally successful. I had become an expert! We flew that combo for a couple of years until I could afford a new 'Fleet' 3-channel Galloping Ghost system, and the age of reliable radio at affordable prices had finally arrived...

I still fly single-channel, and only wish that today's fantastic lightweight, incredibly cheap and reliable systems had been around forty years ago! Pete

The SAM Librarian, Gene Wallock < > will make copies of articles for a nominal fee!

Some of you might remember my silk disaster on the Hayseed, with a covering that looked frilly like a lampshade - NO shrinking at all.

On a recent FFML, one of the guys griped about something similar - and the response was 'read the label'.

SIG Nitrate says..."Do not use nitrate dope for the initial coats on silk. It will not shrink enough to tighten silk well on open framework models." Of course, that is what I used. As for reading the label, it's nitrate dope for goodness sake; been using that for 50+ years - why would I read the label ??

...Al, things have changed ! One of them is that the silk we now use for model covering (my source is "Thai Silks!") has been prepared for use in clothing (such as dress lining) and is PRE-SHRUNK. The only way I know to get around that is to soak the silk in water for a half-hour or more, then keep it good and wet while you cover with it. Pull tight too !

Another thing that's changed is the composition of dope -- SOME dope, anyway. NEVER use low-shrink nitrate for covering. It won't stick well either. Plain old original-formula nitrate is still available -- but you have to make sure that's what you're buying to cover your models with. [JW]

...Howell, I teach for free too. I've been dyeing silkspan for more than 50 years. Some methods work better than others !

Here's the best procedure I've come up with. Do the dyeing in a big flat pan. Cut pieces of silkspan to fit all the areas to be covered, making them each about an inch oversize all around.

As you cut each piece, mark it on its edge with a thin-line laundry marker. This saves plenty of time ! Now apply three good wet coats of PLAIN NITRATE DOPE (see the previous submission for more on this) to every surface the covering will touch. (Sand lightly after the first coat, just enough to remove the fuzz,)

Make a saturated solution of whatever color dye you want to use. Remember that silkspan is thin & translucent, so that when it's dyed and dried, it won't be anywhere near as dark & vivid as the dye itself.

Place the pieces of cut-to-size silkspan into the dye bath. Keep them as flat as possible. Stir them around gently every few minutes, trying to prevent them from becoming crumpled.

Let the silkspan soak in the dye bath as long as you think you need. An hour or more isn't too long ! Then pour the dye down the drain or someplace -- it's not toxic -- while keeping the cut silkspan pieces in the pan.

Next rinse with plain water -- as often as it takes to get rid of most of the excess dye in the material. Again, keep the silkspan pieces (as unwrinkled as possible) in the pan.

Now you're ready to cover with that wet silkspan. Use thinned nitrate dope brushed down through the perimeter of the area being covered. Dope & water mix nicely. Yes, it'll "blush" -- but that will disappear after you apply the sealing coats of dope.

Don't try to pull the covering drum tight while it's wet -- but DO keep the material wet until both sides of a wing or tail piece are covered. (That's to prevent warping.) [JW]

In reply to Al Lidberg's use of starter fluid for model diesels, I have been doing this for years. Here's how I do it:

I have used many brands of starting fluid, not just John Deere. I always check it to see what the major component is. You are looking for dimethyl-ether. Propane and other stuff is the wrong starting fluid. For smaller engines, a can will make a lot of fuel, so this is not a bad way to go.

Purists will have many reasons not to do this, but it has worked well for me and I've not seen any bad effects on engines.

Only thing I have ever tried to get ether out of the can and seems to work well is to just spray it into a tall container such as one of your wife's glass vases. Seemed a lot safer than any scheme to poke a hole in the can.

I used a tall graduate designed for mixing photo chemicals, which was handy because I could measure just how much I needed and leave the rest in the can. Didn't seem to lose enough ether due to spray out the top of the container to make any difference.

Needless to say, you do this outside and leave that lit cigarette some distance away. Paul

SMALLnet Posting post458