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Date: Wed, 6 Dec 2000 03:35:17 -0600
< http://www.eskimo.com/~smallnet >
...Sorry for the long delay between Postings, gang. I've had server
problems; and also desperately needed to reconstruct my computer
room. That even included rebuilding the desk. It had acquired a
severe sag in the middle just from the load of the OLD system.
The new computer is much heavier, and for safety's sake I've had to reinforce the desktop and the monitor hutch. Lots of work required, with my computers disassembled and standing by idle until I got the carpentry and cabinetwork finished... [JW] < > wrote from Louisiana: I still haven't had a chance to get started on my Playboy yet. I've been so busy with school and band I've only had time to finish up an Aerostar .20 that I have repaired and re-covered parts of. It's an ugly green so I decided to utilize it and make it look like a military recon plane. Thought I would have a little fun with it. It has an O.S. .25 for power so It ought to fly pretty smooth and not quite too fast. I went to Mr. LeRay's house not too long ago, and for some reason I got the urge to create some balsa dust, and built a nice little HL glider with about a 16" wingspan. But when I finished, to our surprise it didn't need any nose weight. In fact, I had to sand some wood off to get a proper glide so I was very pleased. It turned out to weigh a whopping 3/10 of an ounce. Just for fun we went out the next day with a couple of his L'il gliders too, and just had a blast, even though the wind was blowing about 400 Mph, resulting in looooooooooonnnnggggg flights all the way across the field and encounters with balsa-eating trees a couple of times. But we came home with all we brought out with us, so it was a good day, no doubt.
...This looks like a good place to insert a request: PLEASE sign
your SMALLnet contributions! SMALLnet isn't a chat room.
We're all REAL people (I think) and there's no need for hiding
your identity from the rest of us. [JW]
David Williams < > reports: I've just heard that Balsacraft are closing the whole operation in the UK, and are setting up in the Czech Republic. The wages there are 5 pounds per day, as opposed to 5 pounds per hour here. The kits will be shipped by the container load and sold by a distributor over here. It's a bit sad really, but that's the way it goes. BEST WISHES, David Williams BOLTON, ENGLAND < > anonymously contributed: The interest in my little 1/2A biplane project has amazed me. Those that want a peek can go to: < http://members.aol.com/cfiimei/biplane.html > < > writes from Wormwood Scrubbs: I have just completed a winter project: A 16" wingspan Sukhoi 31 weighing 3 ounces 21 grams. It is powered by a Cox TD .010 with a separate tank. Servos are Hitec 50's, with a Hitec Feather 4-channel Receiver. Only 2 moving surfaces: elevator and ailerons. It flies very fast for about 5-8 minutes. It seems that now more than ever before it's possible to get some really small planes up there, thanks to micro R/C gear. Surely there is now a hole in the market for someone to come along and fill, since Cox has disappeared and left us with no .010 or.020 engines. Who's going to take up the gauntlet? Wormwood SMALLsters
...Probably nobody. There just aren't enough model BUILDERS any
more to make it practicable for a company to tool up & manufacture
tiny glow motors. Those have as many precision parts as a .40,
yet most model engine buyers expect a small motor to cost less
than a big one. However, there ARE a lot of tiny DIESELS on the
market. I know of none with a throttle smaller than the PAW .03,
but there are some .012 and .015 diesels for sale now. I think
Dave Larkin has a few available... [JW]
Peter Havriluk < > wonders: We had the sad event of Dick Gleason's death this year, and at that time his heirs made no statement as to the disposition of his archives and plans. Does anyone know of any news about Dick's collection? Peter Ken Park < > inquires: I've been looking hard for a .20-size Jim Messer Ercoupe! I would really like to locate a kit or plans for this bird. I've heard Jim Messer has retired and is not doing kits any more. Did anyone buy him out, and or know where plans are available? Ken Dick Schwieren < > wrote: On the Hitec charger: I charge my R/C batteries using a cheap 12 VDC battery charger connected to my 12V field box starter battery, using banana plugs inserted into the jacks that I use for the starter on the power panel. Then I insert the banana plugs on the Hitec charger into the banana plugs from the 12 Volt battery charger. The battery then works as a sink for the Hitec charger, to smooth out the voltage ripple. Try it and save yourself the expense of a DC power supply. Dick
...Speaking of DC power supplies, high-quality ones can be
obtained FREE. I know because I got one -- a power supply from
an old computer. Computer repair services have these things
lying about; all you have to do is ask. [JW]
Larry Benson < > submitted: l recently returned to the hobby after a long absence (about 20 years) and enjoy this forum very much. l have used the information from it a lot. l have a dumb question (will seem that way to some): I'm installing a Tower Hobbies 3000 (l think it is made by Futaba ) in my plane using a Wattage lC-550 Electronic Speed Control. I'm not sure about the hook-up. The ESC plug is not keyed, so it will go in either way. l don't want to burn it up hooking it up the wrong way. The wires coming from the ESC are brown, red, orange left to right. The Tower stuff wires are white, red, black left to right. l see no markings on the ESC to determine which one is the signal wire. How do l determine this ? Larry Benson Allen Wiltz < > wrote: Recently I acquired a new G-Mark .03 R/C engine. Several attempts have failed to get it started. The problem seemed to be a leak at the top of the glow plug/head. After sealing it still won't start. Since this engine has been out of production for several years, does anyone know where glow plugs for this engine are available -- and has anyone had experience with this engine? Allen
...Allen, I own a couple of those little G-Marks. Before the PAW
.03 came out, the .03 G-Mark was the smallest reliable-throttling
model engine available. I loved mine. However, they require as
much careful breaking-in as a "big motor" before they perform at
their best.
As for G-Mark .03 glow heads, those have become rare. Bill Cannon (the first manufacturer of micro-size proportional R/C equipment) was the sole USA importer of G-Marks at the time the owner of G-Mark died. Bill passed the word to his friends that there would be no more G-Marks, and a bunch of us (I was one) bought up all the remaining stock. It should be possible to somehow adapt the little G-Mark's glow head to accept a standard plug of some kind. I've never seen that done, but I think it could be. [JW] Jack Dickerson < > is grateful: Hey SMALLsters, Thanks for the help. I got 6 replies and all were VERY helpful. Got a Hitec Model 330 and it does a great job. Thanks again. Jack Dickerson Mike Gillihan < > inquires: Has anyone had any experience with CO2 "jet" propelled aircraft? I came across the plans for a small FF of this variety some years ago in Popular Science, and was wondering if anyone had experimented. The aircraft had a Bill Burns gun CO2 cartridge mounted in the fuselage, and was launched by piercing the nipple of the cartridge and letting the aircraft blast away via compressed gas. Mike Gillihan
...Mike, in the late 1940's there was brief, but intense interest
in "jet-propelled" models powered by CO2 capsules. This was mainly
in cars; there were a couple of model boat and airplane kits too,
but those never became popular because of the short "running time".
At best a CO2 capsule only produces significant thrust for a few seconds. I used to demonstrate Monogram "Mono-Jet" cars on a coast-to-coast hobby show tour, and I'd say that the capsule thrust lasted less than 5 seconds. Around that time the Lockheed Employees Recreation Club (LERC) in Burbank, California had regular competitions for CO2 "jet cars". They enjoyed the use of a long, linoleum-floored corridor, and set up a really professional straightline race course, complete with a precision electronic timing system -- no easy or inexpensive task in 1948! As I remember, before interest died down and this activity came to a halt, speeds over 100 mph had been reached. The fastest cars had razor-thin wheels and a bare minimum of "body". A lot of experimentation went into the "launching devices" too. It made considerable difference just how big a hole got punched into the end of the capsule. (That was done with a hardened steel phono- graph needle -- I'll bet few SMALLsters can remember those, although in the late 1940's those were as common as pennies all over America, for playing 78 rpm "big band" records...) Anyway, even with the best brains at Lockheed striving to maximize the performance of these CO2 "jet cars", the fundamental limitation remained: extremely short power duration. That's why planes and boats never made it with that kind of propulsion. I tried a Ray-O-Jet myself once, around 1947. Never got a decent flight out of it. That's because by the time I pierced the capsule and got set to launch, practically all the power was gone. (Maybe my "piercer" punched too big a hole.) Berkeley sold an all-sheet-balsa profile model called a Cat-O-Jet, which used the "piercer" as a launching gun, and that MAY have worked. I've never seen one in the air, however. [JW] < > contributed: I have been interested for some time now in the idea of making replicas of the compressed air motors detailed in Bert Pond's excellent book on the subject. Also have obtained a construction article on the Ott compressed air motor. I plan to use 2-liter pop bottles for air tanks. Now for my dilemma: Has anyone out there actually used the largest Gasparin CO2 motor? Can anyone speak from direct experience with this motor? Ditto, the same for the Hoosier Whirlwind and Joe Ott C.A. motors. I am trying to ensure a correct path in my pursuit of building C.A. motors for outdoor R/C work, versus my perceived hassles of the albeit smaller CO2 tank and system. It would be great if Eut Tileston were in on our group, as he had also designed a high performance pusher some years back. The benefit of his experience and design work would be great. Having a large lathe and shaper, I was eyeing a new Sakai lathe for this work. Anyone out there knowledgeable or interested in CA and/or CO2 R/C projects?
...Say, "anonymous", I've been there and done that! Briefly, I own
a couple of Whirlwinds, and flew one in a rudder-only R/C model.
I'll probably do it again, too -- but the original airplane is no more.
It was called the Awkward Auk, and was a FAT fuselaged craft about 5 foot span, 600 square inches, all built-up and covered with dyed Silkspan. I used a 2-liter pop bottle for a tank, which was what Bert Pond originally recommended as a preferred air reservoir for the Whirlwind. Later Bert had second thoughts. He and I both conducted burst tests on 2-liter bottles (inside a burlap bag for safety). I was NEVER able to burst one, but Bert said he exploded two at around 210 psig. (He said it sounded like a mortar bomb going off -- Bert had been an artillery officer in WW2.) I could never manage to pass 200 psig with my bicycle pump. In fact, I had a hard time exceeding 160 psig. But it worried Bert that my 2-liter pop bottles took a "permanent set" after being pressurized to 160 psig. They looked like eggplants afterwards. Bert considered that a sign of incipient failure, but I liked to think of it as evidence of "pre-stressing". Anyway, Bert won me over to his way of thinking, and I'd planned to build a new fuselage for the Awkward Auk, to contain TWO one-liter pop bottles like a pair of binoculars. The one-liter bottles -- at least the round-bottomed ones then standard -- could take 210 psig safely. We never used more than 160 for flying, and I think the SAM rules for compressed air power limit the inflation pressure to 150 psig. Whirlwind motors are smooth-running and very reliable. However, they are also exceedingly fragile. They cannot take any impact without bending something. For that reason, my Auk had its motor mounted on a pylon well above the nose; and I used a hand-carved folding prop, just like you'd see on a prewar Wakefield rubber- powered model. No, that wasn't to improve the glide -- it was to protect the Whirlwind's slender, soft-steel shaft from being bent in case of a noseover. Another peculiarity of the Whirlwind (and similar compressed air motors) is that their con rods are expendable. It's very hard to keep those lubricated and free from dust. But it's easy to replace them -- they're right out in the open after all. If you'd like to mess around with compressed air power, the very easiest way to get a start is with an Air Hogs power unit. The whole Air Hogs package costs under $30, and the motor unit and pump are easily worth that. The foam ARF model flies too; but I recommend sending to Model Aviation and ordering plans for Ken Johnson's air-powered free flight plane. That uses a stock Air Hogs motor and tank, and really performs. I've seen it in action, and it is IMPRESSIVE. With one of the new GWS receivers and a single Pico servo, using a 120 mAh NiMH pack would provide a one-ounce rudder-only R/C installation -- well within the lifting capabilities of Ken's design. The neatest thing (to my way of thinking) about the Air Hogs motor is its steady power output. The Whirlwind is more like a rubber motor: maximum power at the start, with a steady decline in output until the tank is empty. But the ingenious "head valving" used in the Air Hogs motor provides almost constant power for about 2/3 of the motor run. Maybe you could figure out a way of making a metal version of the Air Hogs motor -- perhaps even with multi-cylinders. [JW] Curran Harvey < > asks: This is more of a request for help than a contribution. I am finishing a Clancy Yard Bee, and am exploring powering it with CO2. I would like to use a Gasparin G300 or a GMW73T twin cylinder with a speed control. Has any one used a G300 with a Gasparin speed control? Any help will be greatly appreciated. Curran Harvey { phone - (410) 828-6483 (call collect) }
...Curran, if you want to get one of the Gasparin GMW73T's,
you'd better hurry. In today's snail mail arrived a letter from Roy
Hanson, saying that production of the ball-bearing "73" models
has been limited to 450 TOTAL. Stefan Gasparin will be
replacing that design with a plain-bearing model early in 2001.
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