La Coupe Des Barons 2024.

[David Davis]

9 minutes ago, Martin Dance 1 said:

With all of the design and construction mods you are planning  La coupe de Barons, a fun fly competition is taking on a seriously competitive  edge. Next it'll become an international  competition. Oh it is already, unles you've taken French citizenship.😀

 

The first time I entered they shoved a microphone under my nose and asked where I was from. I said, " La Creuse!" Then they asked me where I was born. I replied, "Shropshire, Angleterre." The man with the microphone said that the competition was now "La Coupe Des Barons International."

 

Apparently a German and a Swiss national are regular competitors and this year there will be at least two Englishmen competing if all goes well.

 

PS. I haven't taken French citizenship though I know several who have. I have a residency permit until 2031!

[David Davis]

I have decided to repair Boris's wing first.

 

The starboard wing snapped off at the wing route. After a considerable amount of fettling I've got this far. I've simply added two new plywood dihedral braces over the old ones because I doubt that I could have removed the old dihedral braces without damaging the main spars at the same time. This will add a little weight butI don't think it will make much difference.

 

This is the standard Baron wing, it has a total of nine spars including the leading and trailing edges. Four of these spars are arranged in pairs and they are all balsa except for the main spars which are basswood.

 

The rest of the airframe is undamaged though a glue joint at the tail seems to have sprung. I will investigate.

 

I've bought some new grey covering film marketed by Kavan. It is a shade darker than the Oracover which covers the rest of the model, not that that greatly concerns me. I am going to cover the lower surface of one of the wings in black film and the other in white, rather like the early British fighters of the Second World War. This is to aid orientation.

 

 

 

 

[Paul De Tourtoulon]

Looks more like a wing from a Vicomte.

[David Davis]

58 minutes ago, Paul De Tourtoulon said:

Looks more like a wing from a Vicomte.

 

 

A Vicomte was a Baron made under license by Svenson.

[Paul De Tourtoulon]

1 hour ago, David Davis said:

 

 

A Vicomte was a Baron made under license by Svenson.

I know, the Vicomte wing tip was as in your photo, I bought and built one in 1984 and read the french 'build ' on it where the so called builder ( typical french press ) said that it was more difficult to build as the wing was under-cambered so difficult to get the film to stick.

 

 I fitted mine with floats as at the time I was living by the sea and a nice big lake with an OS .35Fp.

[David Davis]

Apropos of wing tips, the standard wing tip of the Baron is effectively a triangle 24cms x 10cms and under-cambered to echo the sort of wing sections in use during the Great War but these wing tips are not compulsory. Last year's event was won by Christian Bolis flying the No.2 Baron which has wing tips and tail surfaces similar a Vought F4U Corsair. Others simply build their wings with squared off tips.

 

So a question for those with superior aerodynamic knowledge.

 

Would there be any advantage in changing the shape of the wing tip on the new wing which I will be building for the British Baron?

 

The Ukrainian Baron will have a stock Baron wing.

 

Video of last year's event attached. I crashed out in the first round and finished second to last. I hope for an improvement this year!

 

https://www.youtube.com/watch?v=JuMm24PTZ_Y

[J D 8]

 When it comes to aerodynamic considerations for a rudder elevator type like the Baron it is more critical to have the right amount of dihedral than wing tip shape, to little and model becomes rather touchy on the rudder and more difficult to fly straight. [ think you have found this] To much and strange things happen.

If you watch pigeons on the glide for some reason they hold in a high amount of dihedral and it looks like hard work.

    I would say keep your Barons [ aerodynamic ] as alike as possible so they perform the same when you swop over, even make a basic no frills one to practice with. Good luck. John.

[David Davis]

Thank you John, I'll do my best to make them as identical as possible though the wing structure will be different.

 

I have discovered several metres of flourescent yellow film in the workshop. Perhaps I'll use that to cover Boris's wing retaining the black and white undersides for the British Baron. Normally the darker covering goes on the underside of the wing doesn't it?

Edited January 13 by David Davis

[J D 8]

  Does not matter about the structure being the same, just the aerodynamic's, dihedral, wing section and may help if aircraft weight is close.

         Yes darker on the bottom is best, all colours just become blackish at distance at a distance so helps to start darker. Good thing with the Barron is it has a distinctive profile that helps show which way up it is.

[David Davis]

Boris's newly repaired wing makes the rest of the model look scruffy, besides the new grey film does match the older covering. I have decided to recover the fuselage and tail surfaces too, that way I'll be better able to check for structural damage.

 

I've been impressed by UHU Por impact adhesive. Boris is mounted on a block of depron. You can pick up him up by the head and wave the wing about no bother! I'm looking forward to using this glue on the British Baron with its depron wing ribs. Has anyone used this glue as a canopy glue?

[ronron]

hi David, i just find this interesting tread, i'm from south of  france number 230, we are 7 seven pilots from our area to go to the baron cup. in the picture of your baron i can see you have a low tale. the baron has a problem of V longitudinal, i put a 4mm wedge under the trailing edge, and i found out that the CG was between 95mm and 105mm for my svenson regular Vicomte with Predim RC, i have no load on the front.

[David Davis]

12 hours ago, ronron said:

hi David, i just find this interesting tread, i'm from south of  france number 230, we are 7 seven pilots from our area to go to the baron cup. in the picture of your baron i can see you have a low tale. the baron has a problem of V longitudinal, i put a 4mm wedge under the trailing edge, and i found out that the CG was between 95mm and 105mm for my svenson regular Vicomte with Predim RC, i have no load on the front.

 

Hi Ronron,

 

Thank you for the information but it will be difficult to change the incidence of the tailplane on my models as both are firmly glued into place. I'll consider the modification if I have to build another. My Barons are both powered by four-stroke engines so there is no need for weight in the front. I give a prize to the leading pilot who uses a four-stroke engine in the competition. I won my own prize in 2021 so I gave it to the second man!

 

Please come over and introduce yourself in June. I speak French fairly well. I will be flying the number 247 Baron finished in either British or Ukrainian markings something like in the picture below. There may be another expatriate Englishman in the competition. He lives up in the Somme region. Several of my French club mates participated in the competition in 2019 but they now think it's too far to drive! 😄

[David Davis]

I have been working on my reserve Baron.

Once I'd repaired the wing, the fuselage and tailplane looked scruffy so I removed the old covering, repaired any damage and re-covered them. The grey didn't match anyway because the film was from two different manufacturers. I've used off-cutts from rolls of flourescent yellow and orange. I should be able to see it in the sky! I hope to maiden it this weekend.

[David Davis]

Too cold to go flying so I started work on my other Baron's new wing. I am using depron for the wing ribs. I have never used it before, neither have I used De Luxe Materials' Super Phatic or UHU POR before. They are both excellent.

 

[David Davis]

I flew the Reserve Baron yesterday for the first time since repair. We had a windless and sunny afternoon though it was a bit cold. The model flew well enough but it still needs a few minor trim alterations. The threads in the Thunder Tiger 54's exhaust port have stripped but I glued the exhaust pipe in place with half hour epoxy. It works but you cannot change the position of the exhaust pipe of course. The orange and flourescent yellow patches, which I'd cut from remnants, showed up well in flight.

 

Work continues on the British Baron with its depron wing ribs. I posted the same picture of the wing under construction on a French website Le Confrerie Des Barons or the Brotherhood of Barons in English. Imagine my surprise when the designer of the Baron, Christian Chauzit himself expressed interest in my experiment!

[David Davis]

Just a brief update on my preparations for La Coupe Des Barons.

 

The new wing is almost finished and I'm pleased with the way it's turned out. A Baron's wing as kitted features four spars arranged in two pairs and twenty-eight wing ribs. One pair of spars is made from basswood, the other pair from balsa. My wing has eighteen balsa capped depron wing ribs, a built up trailing edge, a carbon fibre leading edge and three balsa spars. The forward part of the wing is fully sheeted resulting in a D section. The wing is extremely light and rigid. There's still a bit of cutting, shaping and sanding to be done, the attachment points for the wing warping wires need to be glued into place and the front section needs to finished off before I start the covering process. Then there's the pilot, gun and cables which need to be fitted. 

 

Earlier this morning I took the opportunity to measure the wingspans of all three wings. According to the infomation on my kit box a Baron's wing should measure 155cms or 61 inches in the wingspan. The Ukrainian Baron's wing measures 60 inches, the new wing measures 62 inches but the wing with the lower dihedral currently fitted to the British Baron measures only 57 inches. No wonder this model is more difficult to fly! I did not deliberately enlarge the new wing but there we are, it's within 10% of the original!

 

As stated above I've already flown Boris Baron but since then I've received the roundels and numbers from Lee at Pyramid Models so here's what it looks like in fighting trim. You could say that it's colourful! The Flourescent Yellow stands out really well so I intend to incorporate some of this colour into the colour scheme of the new wing.

 

The weather forecast is good for tomorrow so I plan to fly Boris.

[David Davis]

A couple of better pictures of the new wing. There's still a bit of filling and sanding to be done but the basic construction is nearly finished. The wing weighs 350 grammes or 12 ozs and is very rigid.

[Paul De Tourtoulon]

Looking good, 'however', you will start a fuel row if you don't censure le cardboard box underneath it.😂

[David Davis]

Laser low oil variant. Smuggled from England in September! 😏

[David Davis]

The new wing is covered and fitted to the fuselage. It is 3 ozs (80grammes) lighter and 2 inches (5 cms) greater in the wingspan than the Ukrainian wing pictured above. My fault but it's still within the dimensions allowed in the rules! There are a few cosmetic jobs remaining and I need to add the British roundels, the gun and the wing warping wires.

 

Incidentally the first British wing seen in my post of 24th December was only 57 inches (145cms) in the wingspan. No wonder it flew so quickly!  According to the kit box a Baron's wing should be 155cms!

[David Davis]

I flew the Baron with its new wing yesterday. It flew very well but the engine ran out of fuel as I was lined up for a landing and it landed undamaged in a fallow field. I have since fitted a bigger tank. It requires a little cosmetic work, some fine tuning of the engine and I need to make up some sort of gun for it to comply with the rules of La Coupe Des Barons. I'm very pleased with the new lightweight wing. Incidentally I have covered the underside of the port wing in black film and the underside of the starboard wing in white similar to the early WW2 RAF fighters.

[David Davis]

Both Bertie and Boris Baron are ready for La Coupe. There are a few cosmetic jobs to do but they are in serviceable condition I'm just waiting for the wind and rain to stop before flying them.

 

Technical details:

                              Bertie has a wingspan about 2.5 inches or 6cms bigger than standard, (my fault I changed the internal structure of the wing!) the airframe weight is 2.1kgs and the model is powered by a Magnum 52.

                              Boris has the standard wing, weighs 2.2kgs and is powered by a Thunder Tiger 54. I'm told that my models are rather heavy. The weight of the four-stroke doesn't help of course but I used basswood for the fuselage longerons and though they have added weight, both models have crashed without the fuselage being damaged.

 

My dog is such a diva that she has to photo-bomb at every opportunity!

                             

[David Davis]

I took both Barons to the flying field yesterday. I programmed in 5% down elevator with the throttle stick above 75% travel. For a computer phobe like me that's quite an achievement! This had the effect of stopping the model from climbing at high speed. I must do the same for the other one.

 

The Ukrainian Baron, Boris, is fitted with a Thunder Tiger 54 FS. The threads in the exhaust port are worn and the exhaust pipe keeps working loose. I'll try Loctite but I don't hold out much hope. It's a pity because I've owned that engine from new and it's always given good service. There does not seem to be sufficient metal around the exhaust port to allow for a helicoil insert. Spares are difficult to find. There is a brand new cylinder head on eBay but the seller wants £100 for it. I have at least four OS 52s and 48s. Perhaps I should fit one of those.

 

The British Baron, Bertie, is powered by a Magnum 52 fitted with a Weston four-stroke silencer. This works very well but it is much bigger and heavier than a standard four-stroke silencer. Again when I landed the model yesterday I found that the exhaust pipe was loose. The threads in the exhaust port seem to be sound, I'll try some Loctite and hope for the best. If it continues to work loose I'll fit a conventional silencer. That will be a pity because I've grown to love the sound of the Weston exhaust!

 

Any advice on keeping exhaust pipes in place will be gratefully received.  

 

Edited April 14 by David Davis

[Paul De Tourtoulon]

Good luck with the locktite, it won't work, I have a couple of old motors with the same problem, one I drilled the exhaust port a little deeper and deepened the thread, now it is ok, another I have used the older technique that Rossi used for their piped 2 strokes, a steel ring with a spring around the cylinder head.

[J D 8]

 Hi David, Had the same issue with my Enya 90. Locktite no good, layers of PTFE plumbers tape lasted longer.

Fix that has worked a couple of years now.

 Removed the exhaust header pipe and with it in a vice and the locknut as far down the thread as it would go I heated the end until red hot and then tapped a mandrill [ just a punch ]of slightly Larger diameter than the internal of the pipe. This expanded the end and made for a firm fit in the head [ mine was very loose ] Refitted with Gum gum on thread [ exhaust paste from motor factors]   As an extra I also remote mounted the muffler to reduce strain on the pipe. Cheers, John.