TARMAC Notes for April

 

I was asked recently where the Centre of Gravity (CG) was on my Pluto Vintage team racer.  To be honest, I didn’t know off the top of my head, so I went to check it by the old hold it with two fingers at the balance point and make a guesstimation.  Then due to its shape I found that I couldn’t be too sure at all using that system.  There had to be a better way and this seemed to be the time to re-create an idea that was published in `Stunt News’ not so long ago. 

 

The idea was that if you hang something from a single point, then it will stabilize with the CG immediately below the point of suspension.  How it works with model aeroplanes is that you invert the aircraft, attach three cords tied to a ceiling hook or similar to the dangly bits (wheels), and adjust the cord lengths so that the plane sits wings level and fuselage horizontal.  (You could probably get the CG of the average aeromodeller the same way, but it is hell on the dangly bits.) 

 

Having reached this stage, the CG will be directly beneath the attachment point.  `How nice’ you will be thinking, `But not much use’.  The trick of course is to also attach a plumb bob to the same ceiling hook and it also will be directly below the hook and pointing to the precise CG of your model.  The pictures below may help to make this clearer.

 

 

 

A vintage team racer suspended, wings level and fuselage horizontal in the sling to exactly locate the centre of gravity (CG).  The brass plumb bob points to the spot.

 

 

The model should be suspended with very light cord.  Even button thread or linen thread would be strong enough for most control line models.  Some of the RC fraternity might have to use chains of course.  Due to my skill with perspective drawing, the rather rough sketch above doesn’t look like it, but the fuselage and wings should be set level by adjusting the lengths of the individual cords before any measurements are taken.  The arrow head indicates the location of the plumb bob.

 

There probably aren’t too many control line fliers that haven’t heard of Jim Walker.  For those that don’t know, Jim is the guy that was accepted for many years as the inventor of control line flying although that was disputed later by a chap called Oba St Claire.  Either way, it is indisputable that Jim Walker alone was the first to promote and popularise control line along with all other forms of aeromodelling.  His patents covered many aspects of modeling, including control by sound and his famous folding wing catapult gliders.  His flying skills were something to be wondered at.  Can you imagine being able to successfully fly three control line models at once?  I have enough trouble with one.

 

If you would like to find out a bit more about the amazing activities of Jim and his company `American Junior Models’, you can check out the web page that has been put together as a tribute to him at:                     http://www.americanjuniorclassics.com/        It is well worth a look.

 

 

 

The latest in the flow of stunters that emerge from the workshop of Peter White.  This is his new `All American’ to replace the old one that Peter tells me is getting `A little shabby’.

 

Some years ago, a mate of mine called Dave Cammack gave me a bit of good advice about the techniques of building things.  Dave was a woodworker by trade, but built all sorts of things with a range of materials.  He told me that if you can see what you want, and get your hands to do it, it doesn’t matter what tools and methods you employ.  If the finished product is up to the standard you want, it is OK.  So if you can reproduce an antique mahogany writing desk using just a stone axe and a team of trained Mongolian racing termites, good luck to you.  Just because everyone else does it a certain way does not mean that you have to.  It is always a good idea to ask questions about other peoples methods, but don’t feel bound by them.  Your way could be better – It will at the very least be different.

 

 

Dredged from the TARMAC archives is this shot of the late Len Armour(L) with his McCoy .60 powered speed model and a young Brian Sadler at the 8th Nats.  Photo supplied by Johnny Orr.

 

I see that Top Flite is marketing yet another ARF model.  This one is called the `Score’ and is alleged to be specifically designed for F2B competition.  The construction sounds to be similar to the already successful `Nobler’ ARF, being mainly balsa and ply and it is supplied with a pre-painted fiberglass cowl.  They say that it can be assembled in four to six hours (perhaps they mean forty six hours), is 56 ½ inch span and 677 square inches of wing area.  If this one is as good as the Nobler, they should do well with it.  I wonder who will be the first one to have one here.

 

 

The new Top Flite ARF for F2B.  It is called the `Score’.

 

If any of you budding machinists out there have considered building a small steam engine, I have for sale a full set of genuine, high quality, Stuart Turner un-machined castings for their V10 vertical steam engine.  It is complete with the instruction booklet and they are still in the shrink wrap, so no missing bits.  $100 will part me from them.  If you are interested, email me for more details.

 

 

Another image from the TARMAC archives is this one of Geoff Barnes holding Hans Bertina’s immaculately finished ETA powered B racer.  The model was finished in snow white and iridescent green.  It was given the `Best finished team racer in Australia award at the Strathalbyn Nats in 1963/64.

 

I have been entrusted (poor fools), with the only key to the new flying field at Lumen Christie College.  So after a slow start over the last couple of weeks, I wasn’t in a great rush to get there on the third week of our occupation.  But on arrival I was surprised to see the driveway jam packed with cars and impatient aeromodellers.  Apparently none of them had noticed that on the right hand side of the gate is a large gap or access way in the fence quite large enough to allow the passage of portly aeromodellers carrying aircraft.  They had already worked out for themselves that there is plenty of room for cars on the drive outside the gate.  Once the gate was open, it didn’t take too long for them to take up residence and get flying.  Kim Ashton brought down a veritable airforce of large models, all powered by four stroke engines.  We were privileged to see the maiden flight of his new `Mosquito’ that is powered by two Saito .30 engines.  It is a profile that looks good, sounds good, and flies as well as it looks and sounds.  I also got to see Kevin Cook’s SIG Mustang for the first time.  We had a great day.

 

 

 

Kim Ashton’s DH Mosquito profile.  Powered by 2 Saito .30 engines, the plan was sourced from Peter White’s vast collection.  It weighs 60 ounces and is 60 inch span.  It looks and sounds great in the air, stunts well and Kim is very happy with it.

 

 

Another new arrival at the new TARMAC field is this SIG Mustang built by Kevin Cook.  It is powered by an OS LA .40.

 

The sort of news that we don’t like to hear has come from Mal Bone.  He has had his `Ozone’ control Line Stunter stolen from his shed.  The Ozone is painted white, about 50 inch wingspan with OZONE on one wing and STALKER on the other.  The motor is an ST40 as in Stalker 40.  The Stalker is produced for control line stunt and there are very few here in WA so this combination of model and engine should be easily recognizable.  If any of you should see this outfit please contact Mal Bone on (08) 9401 0460 or (mobile) 0416 456 607 or alternatively, give me a call and I will relay the message.

 

 

 

Finally, from the archives is a chap who has been aeromodelling since castor oil was invented.  Dick Gibbs (L) and Jack Austin seen here in an RAAF PR photo taken at Pearce AFB for National Service in 1951.  The Frog500 Team Racer was built by the photographer Maury Fisher who was a fellow Thermal Thumbers member.  Photo supplied by Dicky Gibbs

 

I used to get a laugh from the tongue in cheek jabs written by the Aeromodeller columnist `Pylonius’.  There was quite often humour and truth in what he had to say.  I was browsing through an old Aeromodeller the other day and saw in one column a bit of both.  I found his thoughts regarding helmets for team racing to be funny.  He writes `Having seen modern team racing in action, it seems to me that anyone venturing within a hundred yards of the screaming monsters would hardly need the added thickness of 1/8th inch of plastic around his skull.’ 

 

Since this column will be the last of a series that I have been writing, largely unaided for almost sixteen years, his next comment that `The thing that I like most about the club newsletter is the way it is disguised as a full orchestra when, in reality, it is a one man band.’ is not all that far from the truth.  Anyway I plan to have a nice rest from the regular slaving over notes that are doomed to soon be protecting the bottom of a parrot’s cage.  If you think that I am laying it on a bit thick when I refer to it as `slaving’, then perhaps you should try doing it for a while.

 

I have been pondering of late what can be done to improve this world we live in, and after earnest consideration, I think that the first step should be the extermination of anyone involved in the making of Rap music.  That would have to be a positive move.

 

In case you’ve been wondering, I'm not a complete idiot. (Some parts are missing.)

 

Charlie Stone                VH4706                      Email  cestone@bigpond.com