David Davis

I turned the model the right way up and got this result. Neither the rudder nor elevator servo has been installed yet neither has the rx battery but putting the pilot into the cockpit, even in the most advanced position, causes the model to tip over. Some cosmetic work to do too.

I've got some in stock. I'll use one.

Of course. I built the model I can chop it up again! Besides, having removed the two servos from the rear fuselage I now have two holes which will give me access to the rear fuselage. Having removed the two servos and the rx battery, the c of g was much better, in fact I'd be quite prepared to fly the model with the c of g in this position. I thought of having one servo under the wing and the other at the rear but as soon as I put one of the servos back into place we went back to a rearward c of g. So I will mount all three servos side by side then use the rx battery to fine-tune the balance point.

Good Morning Gentlemen! Having borrowed the club's c of g apparatus and set the pivots to 4 inches (10 cms) from the leading edge as recommended in the instructions, I put the model in place and as we suspected it was very tail heavy even with the rx battery taped much further forward than one could realistically fit it. I am in the habit of keeping various bits and pieces of my latest build in a tin which once contained Twining's tea. The weight of this tin and it's contents amount to nearly 12 ozs (340 grammes.) With the tin placed on the nose it brings the c of g to an acceptable position. The most obvious next step is to move the two servos from the rear fuselage and to reposition them next to the throttle servo. I will use a closed loop system on the rudder but I'm not sure how to actuate the elevator. I'm considering either snakes or a balsa dowel. Whichever I chose, I'll have to send off for them.

Paragraph 7 in the "Wings" instructions. Part 39.

The fillet is part of the kit Ron. Have a look at Cloud Models version which inspired the scheme I chose, or Galaxy Models own picture.. Yes I noticed the servo lead. The receiver is not installed.

After weeks on very little activity I have made considerable progress in the building of the Mystic over the last few days mainly by laying off the vino! The white undercarriage from Carbon Copy turned up and it's a lovely piece of kit however, it looks too small for the model. This is my fault for not reading the dimensions properly. A rather heavy undercarriage from my WOT 4 XL, which went up in flames in the Great St Valentine's Day LiPo Explosion was fitted and I the rear wheel assembly was taken from my ARTF Acrowot which I landed in a tree, depth perception not being my strong suit! I'm not sure it's heavy enough for the job. All of the control surfaces are now hinged and the servos have been installed. I am trying out Savox metal geared servos on the control surfaces for the first time. They seem to be well made. I still need to make a hatch for the underside between the firewall and the main former. However, last night, with the engine and all servos in place and the rx battery temporarily taped into postion, I decided to check the centre of gravity. I was expecting the model to be nose heavy because the Laser 155 is so much heavier than a 61 two stroke for which the Mystic was designed. However, I found the opposite to be true, it's tail heavy. None of the horns or pushrods have been fitted but they will only exacerbate the situation. I suppose I could add lead to the nose and remove it after flight testing. Alternatively I could move the rudder and elevator servos from the rear fuselage and install them in a more conventional position above the wing alongside the throttle servo. I will borrow the club's cg contraption to ascertain the precise position of the balance point because I've only been able to use my finger tips so far. At the moment the undercarriage is bolted into place with nylon bolts. Would steel bolts be a better option? My landings are not too bad these days but my first landing with this model will be its maiden landing and if I cannot manage to land it on our 8 metre-wide tarmac runway, there's a fair chance of my catching a wheel in a mole hole in the grass strip alongside. As ever, the views of the cognoscenti are keenly sought. PS. The cockpit is only resting in position in the picture below, it's not glued in place. I was expecting the model to be nose heavy so bought a pilot. He is quite big and heavy but I suppose I'll have to leave him out now that the model has turned out to be tail heavy.

I got the dimensions from an advert on a French model shop's website. https://www.flashrc.com/en/radio-controls/48657-radiomaster-tx16s-mkii-max-red-16ch-2-4ghz.html

I've been thinking of buying a Radio Master TX 16S for some time but the price of central heating oil has prevented me from actually buying one! Several have mentioned that the 16S is very large, 287 mm x 129 mm x 184 mm according to the specs. That's 11.3" x 5" x 7.2" for those more used to Imperial measurements. I assumed that 129mm (5")was the depth of the box then it occurred to me that it must include the length of the sticks as well! My Spektrum DX9 measures 180 x 102 x 170 including the length of the sticks (7" x 4" x 6.7"). The Radio Master also weighs 150 grammes or 5ozs heavier. Is the Radio Master Pocket transmitter compatible with Spektrum receivers?

Perhaps polyester over doculam would save on dope.

I would have thought that a heavy model would be more stable because it would be less likely to be blown about in turbulent air than a lighter one. Apparently my Barons are heavier than they should be. I'm hoping for a bit of a breeze in la Coupe Des barons in June! 😏 Of course a heavy model with a cg too far to the rear would be a handful!

Nearly all of my models are powered by four-stroke engines. I have a Magnum 52 and a Thunder Tiger 54 in my Barons and I've found that they do not leave a great deal of oil on the model after a day's flying. A squirt of household cleaner and a swift wipe down with a rag and that's it. I have an old Laser 62 in a Big Guff vintage model. I run this engine on fuel containing 15% oil and I have an extension tube on the silencer which terminates just below the bottom of the fuselage. Some oil is left on the forward underside of the fuselage after a day's flying but otherwise its fine. I use a more modern Laser 80 in a large ARTF clone of the SIG Kadet Senior. I run this engine on the new fuel which contains 7% oil. This hardly leaves any oil on the model at all. My experience leads me to the belief that four-strokes burn the fuel more efficiently and therefore there is less mess to clean up at the end of the day. Not that I mind getting my hands dirty anyway! 😉 This view is reinforced if I ever have to drag out the club's Boomerang trainer currently powered by an Enya 50. This engine being a two stroke leaves the side of the model covered in unburnt oil. Finally, and as a rule of thumb, if your Laser has a vertical glow plug, it's alright to run it on the new 7% fuel. If it has a forward facing glow plug, I'd be inclined to use a fuel containing 15% oil.

I use De Luxe Materials Canopy Glue or UHU POR. Where do you find your small screws Ron?

I had a good afternoon flying both Boris and Bertie. I had no trouble at all with the exhaust pipes on both models. They remained in place with no further tightening. The Loctite was not necessary! However, I had a problem with the Magnum in the British Baron., the carburetor cylinder kept coming undone. I will either have to replace the caburetter or the engine.

I live in France and needed a silencer for my Laser 70. MSL told me directly that they didn't export. I had it sent to my mate in Shrewsbury which is where I'm from.

Thank you for the advice gentlemen. I'll see if my local motor factors have gum gum in stock.

,,,and just to add my two pennorth, some glow engines need time to run in before they'll function perfectly.

Why this reluctance to entertain the glow engine ToTo? Its only a matter of adjusting two needle valves and in most cases once the low speed needle is adjusted it may be left alone for years at a time.

If I were looking for advice on WW2 warbirds of about 5-6 feet in the wingspan, Jonathan Harper would be the first person I would approach. He is a very experienced builder and flyer of this type of aircraft and until he started his new job he was the development engineer for Laser Engines, a British four-stroke which you may have heard of.

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.

Temperatures touching 25C in the northern Creuse with light winds. I flew my Big Guff twice, my Ukrainian Baron twice and my British Baron once. Bertie, my British Baron is just about set up perfectly for La Coupe Des Barons in June. Another club member who used to fly in the Eighties but who has lacked confidence to get back into flying, finally found the confidence to fly his expensive ARTF 3D model powered by a 60cc engine. He managed to take off, fly about and execute some aerobatic manouvres successfully. This will make him more confident in future. My dog was a bit uncomfortable in the heat.

I still haven't invested in a Radiomaster transmitter because central heating oil and van repairs have had first call on my money! There is a basic trainer in our club's workshop which anybody can use. However, its fitted with a Futaba receiver. I realise that a Radiomaster transmitter will work with Spektum receivers but can you connect a Radiomaster transmitter to a Futaba receiver?

If you're into building Bas I'd recommend the Radio Queen as a basic trainer. It's very stable in light winds and with repeated flights it instills confidence in a novice before he moves on to an aileron trainer. I used to have one with an i/c engine years ago which I used to give elderly novices their first experience of radio controlled flight. It's one of the two models I regret selling. The other was a Flair Hooligan. By chance they were both pictured on the same photograph! If anyone builds a Radio Queen make sure that you don't overpower it. We tried three different electric motors before finding one which flew the model nicely. if fitting an i/c engine a 40 four-stroke would be a good match. The plans show the engine bearers spaced for a 2.5 cc (0.15 cu.ins) diesel!

For the last three years I have been trying to teach my Belgian mate Frans both how to build how to fly. He's built a Ben Buckle Junior 60 and a Radio Queen but I was on the point of suggesting that he had a few sessions with another instructor when he went solo this morning for the first time on the Radio Queen! The weather was perfect, he flew the first two flights with me on the buddy box but I did not have to intervene at all from take-off to landing so I persuaded him to go solo on the third flight which he did. We had a beer afterwards to celebrate the occasion! 😆

...and it's obtainable from Model Shop Leeds and most other good model shops. https://www.modelshopleeds.co.uk/catalog/product_info.php?cPath=291_1011&products_id=79264