General Aeromodelling Discussion

Dr Dave / Joseph

As a youngster in SA back in the 70s, I used to get taken to the local RC flying club by a neighbour but never got to fly one myself - I just helped out retrieving planes etc. The local model shop was, IIRC, run by a Mr Platt who was apparently quite well known in the RC world.

For Christmas one year I did get a control-line Cox .049 Piper Cub - after a while trying to get it started, my dad said "I'll show you how to do it" and managed about 270 degrees with a steep climb, followed by a crash dive into the concrete driveway. I salvaged the engine and later built a solid balsa control-line model using it, but have never flown it. Still have it though... To be fair to my dad, he was an experienced modeller, having made a lot of solid wooden models in his younger days, it was just the speed of the Cub that surprised him (and looking back, I think we should have had longer lines). He helped me make (or rather made for me) a rubber powered free-flight model - I think it was a Keil-Kraft? - that worked well. Radio control was just too expensive to consider in those days.

Rob

Pulse Jet Leaf valve - Hi Tug, I made the original leaf valve (petal Valve) out of 0.015" shim stock having borrowed a pair of case hardened steel plates that had been made to the same dimensions as the leaves. The shim stock was clamped between the 2 plates and then filed to shape. The final valve was then surface ground to remove any burrs and bring the thickness down to 0.010". Alas, I don't have the plates now or access to a surface grinder.

Bob

Hi Bob, I still have the Engine Encyclopedia with the details in. I'll discuss it with my friend and if we can help I'm sure he'll be only too pleased.

They would certainly be difficult to make without recourse to such kit though of course if one had access to a wire erosion facility it would be a doddle - pity I'm still not at work

Rob, your dad suffered as so many of us did with that first flight - up elevator and following the model with your arm. You describe my first flight perfectly. It was over concrete too but fortunately like yours the engine survived - I was 'helped' by two grown up neighbours who were less than impressed having travelled to the site for two seconds of action and a bag of bits. It would be two more models before I got that first lap - been hooked on it ever since.

Tug

Hi Rob,t

I had exactly the same experience back in the 1950s. My dad gave me an ED Racer engine for my birthday. I built a balsa control line model for it and first (and last) time out it was so fast I destroyed it in half a lap!

Russell

Speedy Builder 5,

If you Google "How to make pulse jet reed valves" there is a Video of an Aussie making them by electro etching, using a simple battery charger and a common salt bath. For some reason I cannot fix a link.

Keith

There is a lovely film made in the 70's by the BBC about the model flying scene called "Wings and Things" which can now be found on YouTube. It brings back fond memories of model flying starting with control line combat, single channel radio with a Super 60 and then on to much larger scale models with full proportional RC. My early model flying some times resulted in a "carrier bag" job but luckily we flew on a river flood plain with soft ground in Footscray Meadows. I also flew my models on Dartford Heath on the site of a WW2 Ack-Ack emplacement which had been demolished but the concrete access roads were left. I remember one guy returning his model to kit form by diving it into the concrete on his first attempt at RC flying.

My model making unfortunately escalated to full size with the rebuild of a Tipsy Nipper in my garage. I think my wife would have preferred I stayed with the models.

My worst model was a Giant bi-plane which we called the "Red Fletton" and my most fun one a "Panic" by Avicraft.

Clive

The good old EE "Brauner" Pulse jet. Used this as a redraw when being taught AutoCAD. Engineering firm I worked at the time had facilities to make a "Flypress" punch and die for the valve but saw the electro-etch video. Another "Round tuit" project although did have a banana shaped tailpipe in stainless made.

Link mentioned by Keith is :- http//aardvark.co.nz/pjet

Regards Ian.

Hi all, early in my aeromodelling days after wading through many rubber powered & towline gliders I decided to take up control line as RC was way above my pay grade as I was still at school (main source of income a paper round at 7 shillings & sixpence a week, that's 37.5 pence if I have converted correctly). As I had an experienced flyer friend who lived about 50 yards down the street he offered to show me the ropes (geddit) As he had given away his example of an indestructible trainer we built one & vowed to keep it for posterity or at least until someone else needed one, so one 36 inch long by 3inch sheet of hard balsa cut into 2 pieces glued together edge to edge, rudimentary fuselage & elevator, surface mounted bellcrank system, had a wedge type fuel tank to hand & an AM15 Diesel engine, tip weight arrived at by trial & error, a machine screw with added washers. There was a grass field behind our houses so somewhere to fly it, after a few adjustments we got it to fly straight & level & it was my turn, after a few fits & starts I managed to keep it out of the brown bit & into the blue bit thence starting a long interest in CL flying. It was not long after this that I created our go to "field box" which was a National Dried Milk tin with 2 nails soldered onto it (with the points cut off) to wind the lines on to it & the customary contents, a Valvespout squeeze bottle of fuel, a pair pliars & a piece of rag! At this point I left school & started an indentured apprenticeship as a skilled turner, handy to have access to have every shape size & sort of machine tool eh & more dosh to boot, now the models got bigger & bigger & also the engines, although we preferred combat screamers like the Cleaver & the Dongus & so it continued for many years.

Happy days & tight lines

BobH

Hell Bob your second name isn't David Curtis is it

Like you I could not afford kits so after my first the KK Ranger never flew do to the pushrod not being soldered in - I'd hoped a balsa brace would do so, but it wasn't to be. it was a means of having to cobble something together from balsa. After the demise of the one mentioned previously - a self design I finally got to fly with a plywood winged biplane and hard wood fuselage made in the school workshops. This wasn't going to fly either - on first attempts stalling at every hand launch. As we left the park I noticed a piece of ground with an embankment - got my mate to launch it at top of mound and kept my arm straight. Bingo - a flight, a full FLIGHT!! and then another and an..... etc.

Sometime after this I made a very similar model to what you describe but a flying wing. AM 15 as well would you believe. Painted in red,yellow and blue Humbrol it survived like nothing else had - I called it WOTIZIT - I DUNNO and David Curtis and I flew it over and over for weeks.

Tight Lines indeed.

Keep it coming guys

Tug

Bob (Speedy Builder 5)

Had a chat with my friend today and he's pretty sure he has petals that will fit the Brauner jet. He is going to check the drawings to be certain and says he will pop some through my door for you if he has them. I'll send you a PM once I hear from him

Tug

There seems to be a pattern here. My first model ‘plane was (I forget the maker) a plastic control line Hurricane with a Wen Mac engine. It didn’t end well. As a thirteen year old, I seem to be a late starter, I knew that an aeroplane had to take off into wind. I broke the model before I learnt that, with CL, you take off down wind...

We then moved to SA and a school friend introduced me to proper model aircraft. A Golden Bee on the front of a balsa and nylon cloth CL combat aircraft. That was magic and the seed was sown!

In contrast to most people, I did have a couple of goes at changing to RC flying. I got so bored with flying too and fro in straight lines that I didn’t last longer than a couple of flights. Not for me.

Edited By DrDave on 27/01/2021 18:26:04

Dr Dave- I think there will be quite a few on here who experienced that short lived, less than a lap, first flight!

It would years before I realised the key to it all (for those early flights) is a straight arm and hand pointed slightly above the model at launch - easy once you know.

I too tried R/C power but like yourself got absolutely nothing from it and it was very short lived. I did fly R/C thermal soaring gliders for quite a few years enjoying the fact that every flight was different and a challenge to better the previous best flight time.

I've been looking for some early photos but have virtually none but around 1968/69 I built this model of a Grumman Bearcat for the first Old Warden Scale Day carrier event.

It was a Model Aircraft magazine plan designed for a 1.5 to 2.5cc engine but as the carrier event is based on speed as well as slow flight I managed to cram an OS40 in there - no silencer of course. I worked off shore at the time and could not make the event so asked a club member to enter and fly it for me. Fortunately for me he decided not to and when I first flew it it was hopelessly tail heavy despite the larger engine. a very large lump of lead cured that but I never did compete with it. The markings were all home made transfers drawn and painted on varnished sticky brown paper strip.

I inherited this pic of 'HMS Flycatcher' from my good friend Stan who owned the local model shop, taken on the day in question

The closest I have to anything of my early days is this larger aerobatic model built from a plan in that years Aeromodeller Annual. This was my first big 'stunt' model and it flew well - 'well' beyond my capabilities that is - powered by a Merco 35

The only thing I have these days to remind me of those early days is this small collection. C/L Aerobatic times of more recent times on the left .......

...... but those early days on the right

Hope that will stir some memories for some - if you have a dried up but whole tube of Humbrol balsa cement from those days lying in your shed to add to it - well....

Regards - Tug

Ramon

Those engines in the case, is the left an ED Hornet ? vaguely remember mine having green anodised cylinder head ?
also the other green cylinder, is that a cut down ED Racer ? the AM15 and the Hunter I recognise.

Emgee

Ramon, that would be a terrific result, the jet last ran on cup final day in about 1967.

Bob Humphrey

Hi Guys - close but not quite

Top shelf is a DC Merlin awaiting a catch up with a good friend.

I doubt few would get the two glow engines top left. They are early Stalker 40 Ukrainian plain bearing engines designed specifically for C/L aerobatic models. As far as I am aware only twelve of this version were made.

Bottom are two temporarily placed diesels an ED Racer reworked to the Pete Buskell 'Tune your Racer' article in the Engine Encyclopaedia and a standard Frog 2.49.

Tony is spot on with the diesels in the left hand side. The AM 10 is the (but not the original one) first engine I had. The 15 is a recent gift, stripped and rebuilt. The Rapier was built from a marine version with a home produced and anodised head and the Hunter of course. What you missed Tony is the DC Bambi sitting atop the tin directly behind and above the AM10.

I found another pic of this case taken a few years ago This was way before I parted with most engines a few years back. All four engines at top left are Stalkers - a 61 LS, a 55 and the two 40's

The motors below have gone but I suddenly I find I have three OS 35S's and three Super Tigre 46's again The Yulon 30 and McCoy 35 have gone but I still have the (reproduction) Oliver Tiger Mk3.

Now surely there must be more of you out there that can enjoy a little nostalgia ?

Regards - Tug

PS Bob, If John has them I'll get them too you in due course but bear with us at the moment

Edited By Ramon Wilson on 28/01/2021 11:45:17

Hi Tony,

though I've not done so myself I'm assured that the Bambi did run. The anodising has completely worn off but there is a trace inside the fins. It was given me quite some time ago by my friend Henry who sadly departed the ranks just on a year ago. It was a thank you for re-boring and making a new piston for a Comp Special for him which he then fitted into a Veron Sea Fury.........

Henry was a stickler for keeping to the original plan requirements down to the last detail. This shows that in the drop off U/C fitted

Also I did this over a 'Dongus' Plan which 'robjon' mentioned the other day - quite topical as only recently I downloaded this tiled version off 'OuterZone' (lots of free plans on there) though at the moment it's still in the think about it stage.

Emgee - You thought my AM 10 may have been an ED Hornet. I don't recall them having a green head as such - I always thought they were much like the Bee and not anodised but there were many variations of most engines of course. The ED Fury 1.49 was made with a green head as was the reed valve version of the Racer - I'm pretty sure at some stage the Hunter was released with a green cylinder head too.

Keep it coming guys - you must have some good memories of this great hobby too?

Regards - Tug

Tony, following your other posts today you may like to watch the videos in this thread as there are some very good 3D printed fuselages being flown as well as modern brushless motors, not those smelly old diesels

3D Printed fuselages Jason whatever next - nearly as bad as those forward thinkers who spoilt every thing with using foam.

Nothing like a bit of balsa dust and ether up the nostrils first thing in the morning

Yep it's all moved on a bit hasn't it - indoor electric powered (efficient) ducted fan power hardly raises an eyebrow.

I well remember the article in Aeromodeller expounding the incredible achievement of one Dieter Schluter in finally solving the true model helicopter mechanics - now you buy them to fit in your hand. Like wise the turbines.

But - some of us oldies like being dinosaurs and enjoy our past

Tug

The smelly old diesels did have one beneficial side effect. The shot of amyl nitrate in the blood when they back-fired and the prop bit you finger...

Oohh! done that a few times Dr D. Someone captured a good one for posterity here below. This was starting one of the 5cc Etas. No blood but it did bloody hurt!

https://www.youtube.com/watch?v=nhsj0N5H_0Q&feature=emb_logo

This last year was asked to help clear another deceased aeromodeller's workshop. His wife asked if I could dispose or use anything in a box of old tins and bottles. Once home found little of use save an unopened bottle of Amy Nitrate - see the top shelf in the first image of the cabinet. I have ether and castor and some IPN but this was a real treat. Wonder if it's still effective?

Tug